79667665 Siemens Power Engineering Guide Transmission Distribution

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Power Engineering Guide Transmission and Distribution

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Transcript of 79667665 Siemens Power Engineering Guide Transmission Distribution

Page 1: 79667665 Siemens Power Engineering Guide Transmission Distribution

Power Engineering GuideTransmission and Distribution

Page 2: 79667665 Siemens Power Engineering Guide Transmission Distribution

Siemens Power Engineering Guide · Transmission & Distribution

Your local representative:

Distributed by:Siemens AktiengesellschaftPower Transmission and Distribution GroupInternational Business Development,Dept. EV IBD

P.O. Box 3220D-91050 ErlangenPhone: ++49-9131-73 4540Fax: ++49-9131-73 4542

Power Transmission and Distributiongroup online:http://www.siemens.ev.de

Power Engineering GuideTransmission and Distribution For further information to each chapter:

High VoltageDesign of Air-insulated Outdoor SubstationsFax.: ++49-9131-73 18 58

Gas-insulated Swichgear for SubstationsFax.: ++49-9131-73 46 62

Gas-insulated Transmission LinesFax.: ++49-9131-734490Circuit Breakers for 72 kV up to 800 kVFax.: ++49-3 03 86-2 58 67

High-voltage Direct Current TransmissionFax.: ++49-9131-73 35 66

Power Compensation in Transmission SystemsFax.: ++49-9131-73 45 54Power Compensation in Distribution SystemsFax.: ++49-9131-73 13 74

Surge ArrestersFax.: ++49-3 03 86-2 67 21

Worldwide Service for High- and Medium-voltage Switchgear and SubstationsFax.: ++49-9131-73 44 49

Medium VoltagePrimary DistributionFax.: ++49-9131-73 46 39Containerized SwitchgearFax.: ++49-68 94-89 12 94

Secondary DistributionFax.: ++49-9131-73 46 36

Medium Voltage DevicesFax.: ++49-9131-73 46 54

Low VoltageSIVACONFax.: ++49-3 41-4 47 04 00

TransformersDistribution TransformersFax.: ++49-70 21-50 85 48

Power TransformersFax.: ++49-9 11-4 34 2147

Power CablesLow- and Medium-Voltage CablesFax.: ++49-9131-73 24 55 and ++49-9131-7310 92High- and Extra High CablesFax.: ++49-9131-73 47 44

Accessories for Low- and Medium-Voltage CablesFax.: ++49-23 31-35 7118

Accessories for High-Voltage CablesFax.: ++49-23 31-35 71 18

Protection and Substation ControlFax.: ++49-911-4 33-85 89

Power Systems ControlSCADA/EMS/DMSFax.: ++49-9 11-4 33-81 22Control Room TechnologyFax.: ++49-911-433-8183

Power Network TelecommunicationFax.: ++49-89-722-2 44 53 or ++49-89-7 22-4 1982

Energy MeteringFax.: ++49-9 11-4 33-80 37

Overhead Power LinesFax.: ++49-9131-72 95 93

System PlanningFax.: ++49-9131-73 44 45

High-Voltage Power Transmission SystemsFax.: ++49-9131-734672

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Siemens Power Engineering Guide · Transmission & Distribution

Contents

High Voltage

Medium Voltage

Low Voltage

Transformers

Power Cables

Protection and Substation Control

Power Systems Control

Energy Metering

Overhead Power Lines

System Planning

High-Voltage Power Transmission Systems

Annex: Conversion Factors and TablesSupplement: Facts and Figures

Adress Index of Local Siemens Partners

ForewordGeneral Introduction

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Siemens Power Engineering Guide · Transmission & Distribution

Quality and Environmental Policy

Quality – Our first priority

Transmission and distribution equipmentfrom Siemens means worldwide activitiesin engineering, design, development, man-ufacturing and service.The Power Transmission and DistributionGroup of Siemens AG, with all of its divi-sions and relevant locations, has beenawarded and maintains certification toDIN/ISO 9001 (EN 29001).

Certified quality

Siemens Quality Management Systemgives our customers confidence in thequality of Siemens products and services.Certified to be in compliance withDIN/ISO 9001 (EN 29001), it is the reg-istered proof of our reliabilty.

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Siemens Power Engineering Guide · Transmission & Distribution

Siemens AG is one of the world’sleading international electrical andelectronics companies.With 370 000 employees in more than190 countries worldwide, the companyis divided into various groups.The Power Transmission and Distribu-tion Group of Siemens with 22 500employees around the world plans,develops, designs, manufactures andmarkets products, systems and com-plete turn-key electrical infrastructureinstallations. These involve high-voltageand HVDC, medium-voltage and low-voltage components and systems,switchyards, switchgear and switch-boards, transformers, cables, telecon-trol systems and protection relays,network and substation control, power-factor correction and load-flow man-agement system. Also included are therequired software, application engi-neering and technical services.The group owns a growing number ofengineering and manufacturing facili-ties. Presently we account for 57 plantsand more than 70 joint ventures inmore than 100 countries throughout theworld. All plants are, or are in the pro-cess of being certified to ISO 9000/9001practices. This is of significant benefitfor our customers. Our local manufac-turing capability makes us strong inglobal sourcing, since we manufactureproducts to IEC as well as ANSI/NEMAstandards in plants at various locationsaround the world.

This Power Engineering Guide is de-vised as an aid to electrical engineerswho are engaged in the planning andspecifying of electrical power genera-tion, transmission, distribution, control,and utilization systems. Care has beentaken to include the most importantapplication, performance, physical andshipping data of the equipment listed inthe guide which is needed to performpreliminary layout and engineeringtasks for industrial- and utility-type in-stallations.The equipment listed in this guide isdesigned, rated, manufactured andtested in accordance with the Interna-tional Electrotechnical Commissions(IEC) recommendations.However, a number of standardizedequipment items in this guide are de-signed to take other national standardsinto account besides the above codes,and can be rated and tested to ANSI/NEMA, BS, CSA, etc. On top of that, wemanufacture a comprehensive range oftransmission and distribution equipmentspecifically to ANSI/NEMA codes andregulations.Two thirds of our product range isless than five years old. For our cus-tomers this means energy efficiency,environmental compatibility, reliabilityand reduced life cycle cost.For details, please see the individualproduct listings or inquire.Whenever you need additional infor-mation to select suitable products fromthis guide, or when questions abouttheir application arise, simply call yourlocal Siemens office.

Foreword by the Executive Management

Siemens Power Transmission and Dis-tribution Group is capable of providingeverything you would expect from anelectrical engineering company with aglobal reach.The Power Transmission and Distribu-tion Group is prepared and competent,to perform all tasks and activities in-volving transmission and distributionof electrical energy.Siemens Power Transmission andDistribution Group is active worldwidein the field of power systems and com-ponents, protection, management andcommunication systems (details shownin supplement “Facts and Figures“).Siemens’ service includes the settingup of complete turnkey installations,offers advice, planning, operation andtraining and provides expertise andcommitment as the complexity of thistask requires.Backed by the experience of worldwideprojects, Siemens can always offer itscustomers the optimum cost-effectiveconcept individually tailored to theirneeds.We are there – wherever and when-ever you need us – to help you buildplants better, cheaper and faster.

Klaus VogesVice President

Siemens AktiengesellschaftPower Transmission and Distribution

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Siemens Power Engineering Guide · Transmission & Distribution

HV/HVtransformer level

feeding the subtrans-mission systems

Remotehydro-electricpower station

Generatorunit trans-former

Subtransmission system up to 145 kV

Regional supply system

Urban and/or industrialareas, also with localpower stations

Internal supply system

Large industrial com-plexes also with ownpower generation

Regional supply system

Rural areas

HV/MVStep-down trans-

former level

Interconnected transmission system up to 550 kV

Long-distance transmissionEHV AC up to 800 kV or HV DC

Power generation

Main substation with transformers up to 63 MVA

HV switchgear MV switchgear

General Introduction –Transmission and Distribution

The sum of experience forintegral solutions

The world’s population is on the increaseand the demand for electrical energy inthe developing and newly industrializingnations is growing rapidly. Safe, reliableand environmentally sustainable powertransmission and distribution is thereforeone of the great challenges of our time.Siemens is making an important contribu-tion towards solving this task, with future-oriented technologies for the construction,modernization and expansion of powersystems at all voltage levels.The Siemens Power Engineering GuideTransmission and Distribution gives a shortsummary of the activities and products ofthe Power Transmission and DistributionGroup.Transmission and distribution networks arethe link between power generation and theconsumers, whose requirements for elec-trical energy determine the actual genera-tion. Industry, trade and commerce as wellas public services (transportation and com-munication systems including data pro-cessing), not to mention the private sector(households), are highly dependent upona reliable and adequate energy supply ofhigh quality at utmost economical condi-tions. These are the basic conditions forinstallation and operation of transmissionand distribution systems.

Transmission

The transmission of electrical energy fromthe generating plants, which are locatedunder the major constraints of primary en-ergy supply, cooling facilities and environ-mental impact, to the load centers, whoselocations are dictated by high-density urbanor industrial areas, requires a correspond-ingly extensive transmission system.These mostly interconnected systems, e.g.up to 550 kV, balance the daily and season-al differences between local available gen-erating capacity and load requirements andtransport the energy to the individual re-gions of demand. For long-distances and/orhigh-capacity transmission, extra-high-volt-age levels up to 800 kV or DC transmissionsystems are in use.In interconnected transmission systems,more and more substations for the sub-transmission systems with high-voltagelevels up to 145 kV are needed as closeas possible to the densely populated areas,feeding the regional supply of urban or in-dustrial areas. This calls for space-savingenclosed substations and the applicationof EHV and/or HV cable systems.

Fig. 1: Transmission: Principle configuration of transmission system

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Siemens Power Engineering Guide · Transmission & Distribution

Distribution

In order to feed local medium-voltagedistribution systems of urban, industrial orrural distribution areas, HV/MV main sub-stations are connected to the subtransmis-sion systems. Main substations have tobe located next to the MV load center foreconomical reasons. Thus, the subtrans-mission systems of voltage levels up to145 kV have to penetrate even further intothe populated load centers.The far-reaching power distribution sys-tem in the load center areas is tailored ex-clusively to the needs of users with largenumbers of appliances, lamps, motordrives, heating, chemical processes, etc.Most of these are connected to the low-voltage level.The structure of the low-voltage distri-bution system is determined by load andreliability requirements of the consumers,as well as by nature and dimensions ofthe area to be served. Different consumercharacteristics in public, industrial andcommercial supply will need differentLV network configurations and adequateswitchgear and transformer layout. Espe-cially for industrial supply systems withtheir high number of motors and highcosts for supply interruptions, LV switch-gear design is of great importance forflexible and reliable operation.Independent from individual supply charac-teristics in order to avoid uneconomicalhigh losses, however, the substations withthe MV/LV transformers should be locatedas close as possible to the LV load centersand should therefore be of compact de-sign.The superposed medium-voltage systemhas to be configured to the needs of thesesubstations and the available sources(main substation, generation) and leadsagain to different solutions for urban orrural public supply, industry and large build-ing centers.Despite the individual layout of networks,common philosophy should be an utmostsimple and clear network design to obtain flexible system operation clear protection coordination short fault clearing time and efficient system automation.The wide range of power requirementsfor individual consumers from a few kW tosome MW, together with the high numberof similar network elements, are the maincharacteristics of the distribution systemand the reason for the comparatively highspecific costs. Therefore, utmost standard-ization of equipment and use of mainte-nancefree components are of decisive im-portance for economical system layout.Siemens components and systems caterto these requirements based on worldwideexperience in transmission and distributionnetworks.

Fig. 2: Distribution: Principle configuration of distribution systems

Consumers

MV/LVtransformer

level

Low-voltage supply system

Large buildings withdistributed transformersvertical LV risers andinternal installation per floor

Industrial supply withdistributed transformerswith subdistribution boardand motor control center

Public supplywith pillars andhouse connectionsinternal installation

Local medium-voltage distribution system

Ring type

Connection oflarge consumer

Industrial supplyand large buildings

Public supply

Spot systemFeeder cable

Medium voltage substations

MV/LV substationlooped in MV cableby load-break switch-gear in differentcombinations forindividual substationdesign, transformersup to 1000 kVA

LV fuses

Circuitbreaker

Load-breakswitch

Consumer-connection substation loopedin or connected to feeder cable with circuitbreaker and load-break switches for connec-tion of spot system in different layout

Main substation with transformers up to 63 MVA

HV switchgear MV switchgear

General Introduction –Transmission and Distribution

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Siemens Power Engineering Guide · Transmission & Distribution

General Introduction –Transmission and Distribution

Fig. 3: Protection, operation and control:Principle configuration of operation, protection and communication systems

Power system switchgear

SCADA functions Distributionmanagementfunctions

Network analysis

Power andschedulingapplications

Graficalinformationsystems

Training simulator

System coordination level

Control room equipment

Unit protection– Overcurrent– Distance– Differential etc.

Unit switchinginterlocking

Control

Unit coordination levelOtherunit

Substation protection Substation control Data processing

Switchgearinterlocking

Data and signalinput/output

Automation

Otherunit

Substation coordination level

Power system substation

Power network telecommunication systemsOthersub-stations

Othersub-stations

Power line carriercommunication

Fiber-opticcommunication

Protection, operation and control

Safe, reliable and economical energy sup-ply is also a matter of fast, efficient andreliable system protection, data transmis-sion and processing for system operation.The components required for protectionand operation benefit from the rapid devel-opment of information and communicationtechnology.Modern digital relays provide extensivepossibilities of selective relay setting andprotection coordination for fast fault clear-ing and minimized interruption times. Ad-ditional extensive system data and infor-mation are generated as an essential basisfor systems supervision and control.Powerful data processing and manage-ment system have been developed. Modu-lar and open structures, full-graphics userinterface as well as state-of-the-art appli-cations are a matter of course.Siemens network control systems assurea complete overview of the current oper-ating conditions – from the interconnectedgrid right up to the complete distributionnetwork. This simplifies system manage-ment and at the same time makes it morereliable and more economical. The openarchitecture of the power system controloffers great flexibility for expansion to meetall the demands made and can be integrat-ed into existing installations without anyproblems. Visualization of system behaviorand supply situation by advanced controlroom equipment assist the highly respon-sible function of systems operators.

Overall solutions – System planning

Of crucial importance for the quality ofpower transmission and distribution is theintegration of diverse components to formoverall solutions.Especially in countries where the increasein power consumption is well above theaverage besides the installation of gener-ating capacity, construction and extensionof transmission and distribution systemsmust be developed simultaneously andtogether with equipment for protection,supervision and control. Also, for the exist-ing systems, changing load structure and/or environmental regulations, together withthe need for replacement of aged equip-ment will require new installations.Integral power network solutions are farmore than just a combination of productsand components. Peculiarities in urban de-velopment, protection of the countrysideand of the environment, and the suitabilityfor expansion and harmonious integrationin existing networks are just a few of thefactors which future-oriented power sys-tem planning must take into account.

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High-voltage Switchgear for Substations

Introduction

High-voltage substations form an importantlink in the power transmission chain be-tween generation source and consumer.Two basic designs are possible:

Air-insulated outdoor switchgearof open design (AIS)

AIS are favorably priced high-voltage sub-stations for rated voltages up to 800 kVwhich are popular wherever space restric-tions and environmental circumstances donot have to be considered. The individualelectrical and mechanical components ofan AIS installation are assembled on site.Air-insulated outdoor substations of opendesign are not completely safe to touchand are directly exposed to the effects ofweather and the environment (Fig. 1).

Gas-insulated indoor or outdoorswitchgear (GIS)

GIS compact dimensions and design makeit possible to install substations up to550 kV right in the middle of load centersof urban or industrial areas. Each circuit-breaker bay is factory assembled andincludes the full complement of isolatorswitches, grounding switches (regularor make-proof), instrument transformers,control and protection equipment, inter-locking and monitoring facilities commonlyused for this type of installation. Theearthed metal enclosures of GIS assurenot only insensitivity to contamination butalso safety from electric shock (Fig. 2).

Fig. 1: Outdoor switchgear

Fig. 2: GIS substations in metropolitan areas

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High-voltage Switchgear for Substations

A special application of gas-insulatedequipment are: Gas-insulated transmis-sion lines (GIL)

Gas-insulated transmission lines (GIL)are always used where high-voltage cablescome up against the limits of their per-formance.High-voltage switchgear is normally com-bined with transformers and other equip-ment to complete transformer substationsin order to Step-up from generator voltage level

to high-voltage system (MV/HV) Transform voltage levels within the

high-voltage grid system(HV/HV) Step-down to medium-voltage level

of distribution system (HV/MV)

The High-Voltage Division plans and con-structs individual high-voltage switchgearinstallations or complete transformer sub-stations, comprising high-voltage switch-gear, medium-voltage switchgear, majorcomponents such as transformers, andall ancillary equipment such as auxiliaries,control systems, protective equipment,etc., on a turnkey basis or even as generalcontractor.The spectrum of installations suppliedranges from basic substations with singlebusbar to regional transformer substationswith multiple busbars or 1 1/2 circuit-break-er arrangement for rated voltages up to800 kV, rated currents up to 8000 A andshort-circuit currents up to 100 kA, all overthe world.The services offered range from systemplanning to commissioning and after-salesservice, including training of customer per-sonnel.The process of handling such an installa-tion starts with preparation of a quotation,and proceeds through clarification of theorder, design, manufacture, supply andcost-accounting until the project is finallybilled. Processing such an order hinges onmethodical data processing that in turncontributes to systematic project handling.All these high-voltage installations havein common their high-standard of engi-neering, which covers power systems,steel structures, civil engineering, fire pre-cautions, environmental protection andcontrol systems (Fig. 3).

Every aspect of technology and each workstage is handled by experienced engineers.With the aid of high-performance computerprograms, e.g. the finite element meth-od (FEM), installations can be reliably de-signed even for extreme stresses, suchas those encountered in earthquake zones.All planning documentation is produced onmodern CAD systems; data exchange withother CAD systems is possible via stand-ardized interfaces.By virtue of their active involvement innational and international associations andstandardization bodies, our engineers arealways fully informed of the state of theart, even before a new standard or specifi-cation is published. Our own high-perform-ance, internationally accredited test labora-tories and a certified QA system testify tothe quality of our products and services.

Ancillaryequipment

Design

CivilEngineering

Buildings,roads,foundations

StructuralSteelwork

Gantries andsubstructures

Major com-ponents,

e.g. trans-former

SubstationControl

Control andmonitoring,measurement,protection, etc.

AC/DC

auxililiaries

Surge

diverters

Earthing

syste

m

Pow

er c

able

sC

ontr

ol a

ndsi

gnal

cab

les

Carrier-frequ.

equipment

Ventilation

Lightning

Environmentalprotection

Fireprotection

Fig. 3: Engineering of high-voltage switchgear

Milestones along the road tocertification:

1983: Introduction of a qualitysystem on the basis of Canadianstandard CSA Z299 Level 1.

1989: Certification in accordancewith DIN ISO 9001 by the GermanAssociation for Certification ofQuality Systems (DQS)

1992: Accreditation of the test labora-tories in accordance with DIN EN 45001by the German Accreditation Body forTechnology (DATech).

A worldwide network of liaison and salesoffices, along with the specialist depart-ments in Germany, support and advise ourcustomers in all matters of switchgeartechnology.Siemens has for many years been a lead-ing supplier of high-voltage equipment,regardless of whether AIS, GIS or GIL hasbeen concerned. For example, outdoorsubstations of longitudinal in-line designare still known in many countries underthe Siemens registered tradename “Kiel-linie”. Back in 1968, Siemens supplied theworld’s first GIS substation using SF6 asinsulating and quenching medium. Gas-in-sulated transmission lines have featuredin the range of products since 1976.

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Design of Air-insulated Outdoor Substations

Standards

Air-insulated outdoor substations of opendesign must not be touched. Therefore,air-insulated switchgear (AIS) is always setup in the form of a fenced-in electrical op-erating area, to which authorized personshave access only.Relevant IEC specifications apply to out-door switchgear equipment. Insulationcoordination, including minimum phase-to-phase and phase-to-ground clearances,is effected in accordance with IEC 71.Outdoor switchgear is directly exposed tothe effects of the environment such as theweather. Therefore it has to be designedbased on not only electrical but also envi-ronmental specifications.Currently there is no international standardcovering the setup of air-insulated outdoorsubstations of open design. Siemens de-signs AIS in accordance with DIN/VDEstandards, in line with national standardsor customer specifications.The German standard DIN VDE 0101 (erec-tion of power installations with rated volt-ages above 1 kV) demonstrates typicallythe protective measures and stresses thathave to be taken into consideration for air-insulated switchgear.

Protective measures

Protective measures against direct contact,i. e. protection in the form of covering,obstruction or clearance and appropriatelypositioned protective devices and mini-mum heights.Protective measures against indirect touch-ing by means of relevant grounding meas-ures in accordance with DIN VDE 0141.Protective measures during work onequipment, i.e. during installation mustbe planned such that the specificationsof DIN VDE 0105 (e.g. 5 safety rules) arecomplied with Protective measures during operation,

e.g. use of switchgear interlock equip-ment

Protective measures against voltagesurges and lightning strike

Protective measures against fire, waterand, if applicable, noise insulation.

Stresses

Electrical stresses, e.g. rated current,short-circuit current, adequate creepagedistances and clearances

Mechanical stresses (normal stressing),e.g. weight, static and dynamic loads,ice, wind

Mechanical stresses (exceptionalstresses), e.g. weight and constantloads in simultaneous combination withmaximum switching forces or short-circuit forces, etc.

Special stresses, e.g. caused by instal-lation altitudes of more than 1000 mabove sea level, or earthquakes

Variables affecting switchgearinstallation

Switchgear design is significantly influ-enced by: Minimum clearances (depending on

rated voltages) between various activeparts and between active parts andearth

Arrangement of conductors Rated and short-circuit currents Clarity for operating staff Availability during maintenance work,

redundancy Availability of land and topography Type and arrangement of the busbar

disconnectors

The design of a substation determines itsaccessibility, availability and clarity. Thedesign must therefore be coordinated inclose cooperation with the customer. Thefollowing basic principles apply:Accessibility and availability increase withthe number of busbars. At the same time,however, clarity decreases. Installationsinvolving single busbars require minimuminvestment, but they offer only limited flex-ibility for operation management and main-tenance. Designs involving 1 1/2 and 2 cir-cuit-breaker arrangements assure a highredundancy, but they also entail the high-est costs. Systems with auxiliary or bypassbusbars have proved to be economical.The circuit-breaker of the coupling feederfor the auxiliary bus allows uninterruptedreplacement of each feeder circuit-breaker.For busbars and feeder lines, mostly wireconductors and aluminum are used. Multi-ple conductors are required where currentsare high. Owing to the additional short-circuit forces between the subconductors(pinch effect), however, multiple conduc-tors cause higher mechanical stressing atthe tension points. When wire conductors,particularly multiple conductors, are usedhigher short-circuit currents cause a risenot only in the aforementioned pinch ef-fect but in further force maxima in theevent of swinging and dropping of the con-ductor bundle (cable pull). This in turn re-sults in higher mechanical stresses on theswitchgear components. These effects canbe calculated in an FEM simulation (Fig. 4).

Fig. 4: FEM calculation of deflection of wire conductors in the event of short circuit

Horizontaldisplacement in m

Vertical displacement in m

-1.4 -1.0 -0.6 -0.2 0.2 0.6 1.0 1.4

-1.4

-1.2

-1.0

-0.8

-0.6

-1.6

-1.8

-2.0

-2.20

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When rated and short-circuit currents arehigh, aluminum tubes are increasingly usedto replace wire conductors for busbars andfeeder lines. They can handle rated cur-rents up to 8000 A and short-circuitcurrents up to 80 kA without difficulty.Not only the availability of land, but alsothe lay of the land, the accessibility andlocation of incoming and outgoing over-head lines together with the number oftransformers and voltage levels considera-bly influence the switchgear design aswell. A one- or two-line arrangement, andpossibly a U arrangement, may be theproper solution. Each outdoor switchgear,especially for step-up substations in con-nection with power stations and largetransformer substations in the extra-high-voltage transmission system, is thereforeunique, depending on the local conditions.HV/MV transformer substations of the dis-tribution system, with repeatedly usedequipment and a scheme of one incomingand one outgoing line as well as two trans-formers together with medium-voltageswitchgear and auxiliary equipment, aremore subject to a standardized designfrom the individual power supply compa-nies.

Preferred designs

The multitude of conceivable designs in-clude certain preferred versions, which aredependent on the type and arrangement ofthe busbar disconnectors:

H arrangement

The H arrangement is preferrably used inapplications for feeding industrial consum-ers. Two overhead lines are connectedwith two transformers and interlinked by asingle-bus coupler. Thus each feeder of theswitchgear can be maintained withoutdisturbance of the other feeders. This ar-rangement guarantees a high availability.

Special layout for single busbars upto 145 kV (withdrawable circuit-breakerarrangement)

Further to the H arrangement that is builtin many variants, there are also designsfeaturing withdrawable circuit-breakerswithout disconnectors for this voltagerange. The circuit-breaker is moved electro-hydraulically from the connected positioninto the disconnected position and vice-versa.In comparison with a single busbar withrotary disconnectors, roughly 50% lessground space is required (Fig. 5).

Design of Air-insulated Outdoor Substations

Fig. 5: Substation with withdrawable circuit-breaker

Fig. 6: Substation with rotary disconnector, in-line design

In-line longitudinal layout, with rotarydisconnectors, preferable up to 170 kV

The busbar disconnectors are lined up onebehind the other and parallel to the longitu-dinal axis of the busbar. It is preferable tohave either wire-type or tubular busbarslocated at the top of the feeder conductors.Where tubular busbars are used, gantriesare required for the outgoing overheadlines only. The system design requires onlytwo conductor levels and is therefore clear.If, in the case of duplicate busbars, thesecond busbar is arranged in U-form rela-tive to the first busbar, it is possible to ar-range feeders going out on both sides ofthe busbar without a third conductor level(Fig. 6).

Top view Dimensions in mm

6500

Section A-B Section C-D

A

C

B

D

6500

7000 6500 1330027000

13300

2500

8000 7500

Top view

Section A-A

20500

R1 S1 T1 R2S2T2

8400 1940048300

9000A

A

6500

4500

End bay

Normalbay 9000

8000

2500Dimensions in mm

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Design of Air-insulated Outdoor Substations

Central tower layout with rotarydisconnectors, normally only for 245 kV

The busbar disconnectors are arrangedside by side and parallel to the longitudinalaxis of the feeder. Wire-type busbars locat-ed at the top are commonly used; tubularbusbars are also conceivable. This arrange-ment enables the conductors to be easliyjumpered over the circuit-breakers and thebay width to be made smaller than that ofin-line designs. With three conductor levelsthe system is relatively clear, but the costof the gantries is high (Fig. 7).

Diagonal layout with pantographdisconnectors, preferable up to 245 kV

The pantograph disconnectors are placeddiagonally to the axis of the busbars andfeeder. This results in a very clear, space-saving arrangement. Wire and tubular con-ductors are customary. The busbars canbe located above or below the feeder con-ductors (Fig. 8).

1 1/2 circuit-breaker layout,preferable up to 245 kV

The 1 1/2 circuit-breaker arrangement as-sures high supply reliability; however, ex-penditures for equipment are high as well.The busbar disconnectors are of the panto-graph, rotary and vertical-break type. Verti-cal-break disconnectors are preferred forthe feeders. The busbars located at the topcan be of wire or tubular type. Of advan-tage are the equipment connections, whichare very short and allow even in the caseof multiple conductors that high short-cir-cuit currents are mastered. Two arrange-ments are customary: External busbar, feeders in line with

three conductor levels Internal busbar, feeders in H arrange-

ment with two conductor levels (Fig. 9).

Fig. 7: Central tower design

Fig. 8: Busbar area with pantograph disconnector of diagonal design, rated voltage 420 kV

Fig. 9: 1 1/2 circuit-breaker design

18000

9000

3000Dimensions in mm

12500

16000

7000 17000 17000

Section

10000

10400

Top view

180005000

13300

Dimensions in mm

Bus system By-pass bus

8000 28000 48000 10000

400040005000

29000

4000Dimensions in mm

18000

17500

480008500

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Design of Air-insulated Outdoor Substations

Planning principles

For air-insulated outdoor substations ofopen design, the following planning princi-ples must be taken into account: High reliability

– Reliable mastering of normal andexceptional stresses

– Protection against surges and light-ning strikes

– Protection against surges directlyon the equipment to be protected(e.g. transformer, HV cable)

Good clarity and accessibility– Clear conductor routing with few

conductor levels– Free accessibility to all areas (no

equipment located at inaccessibledepth)

– Adequate protective clearances forinstallation, maintenance and transpor-tation work

– Adequately dimensioned transportroutes

Positive incorporation into surroundings– As few overhead conductors as

possible– Tubular instead of wire-type busbars– Unobtrusive steel structures– Minimal noise and disturbance level

EMC grounding systemfor modern control and protection

Fire precautions and environmentalprotection– Adherence to fire protection speci-

fications and use of flame-retardantand nonflammable materials

– Use of environmentally compatibletechnology and products

For further information please contact:

Fax: ++ 49-9131- 73 18 58

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Gas-insulated Switchgear for Substations

Common characteristic featuresof switchgear installation

Because of its small size and outstandingcompatibility with the environment, SF6 -insulated switchgear (GIS) is gaining con-stantly on other types. Siemens has beena leader in this sector from the very start.The concept of SF6 - insulated metal-en-closed high-voltage switchgear has proveditself in more than 64,000 bay operatingyears in over 5,500 installations in all partsof the world. It offers the following out-standing advantages.

Small space requirements

The availability and price of land play animportant part in selecting the type ofswitchgear to be used. Siting problemsarise in Large towns Industrial conurbations Mountainous regions with narrow

valleys Underground power stationsIn cases such as these, SF6-insulatedswitchgear is replacing conventionalswitchgear because of its very small spacerequirements.

Full protection against contact withlive parts

The all-round metal enclosure affordsmaximum safety to the personnel underall operating and fault conditions.

Protection against pollution

Its metal enclosure fully protects theswitchgear interior against environmentaleffects such as salt deposits in coastalregions, industrial vapors and precipitates,as well as sandstorms. The compactswitchgear can be installed in buildingsof simple design in order to minimize thecost of cleaning and inspection and tomake necessary repairs independent ofweather conditions.

Free choice of installation site

The small site area required for SF6-insu-lated switchgear saves expensive gradingand foundation work, e.g. in permafrostzones. Other advantages are the shorterections times and the fact that switch-gear installed indoors can be servicedregardless of the climate or the weather.

Protection of the environment

The necessity to protect the environmentoften makes it difficult to erect outdoorswitchgear of conventional design, where-as buildings containing compact SF6-insu-lated switchgear can almost always bedesigned so that they blend well with thesurroundings.SF6-insulated metal-enclosed switchgearis, due to the modular system, very flexibleand can meet all requirements of configu-ration given by network design and operat-ing conditions.

Each circuit-breaker bay includes the fullcomplement of disconnecting and ground-ing switches (regular or make-proof),instrument transformers, control and pro-tection equipment, interlocking and moni-toring facilities, commonly used for thistype of installation (Fig. 10).Beside the conventional circuit-breakerfield, other arrangements can be suppliedsuch as single-bus, ring cable with load-break switches and circuit-breakers, single-bus arrangement with bypass-bus, coupler,bay for triplicate bus. Combined circuit-breaker and load-break switch feeder, ringcable with load-break switches, etc. arefurthermore available for the 145 kV level.

Fig. 10: Typical circuit arrangements of SF6-switchgear

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Gas-insulated Switchgear for Substations

Main product range of GISfor substations

SF6 switchgear up to 550 kV(the total product range covers GIS from66 up to 800 kV rated voltage).

The development of the switchgear isalways based on an overall production con-cept, which guarantees the achievementof the high technical standards requiredof the HV switchgear whilst providing themaximum customer benefit.This objective is attained only by incorpo-rating all processes in the quality manage-ment system, which has been introducedand certified according to DIN EN ISO9001 (EN 29001).

Fig. 11: Main product range

Siemens GIS switchgear meets allthe performance, quality and reliabilitydemands such as

Compact space-saving designmeans uncomplicated foundations, a widerange of options in the utilization of space,less space taken up by the switchgear.

Minimal weight by lightweight constructionthrough the use of aluminum-alloy and theexploitation of innovations in developmentsuch as computer-aided design tools.

Safe encapsulationmeans an outstanding level of safetybased on new manufacturing methodsand optimized shape of enclosures.

Environmental compatibilitymeans no restrictions on choice of locationby means of minimum space requirement,extremely low noise emission and effec-tive gas sealing system (leakage < 1% peryear per gas compartment).

Economical transport

means simplified and fast transport andreduced costs because of maximum possi-ble size of shipping units.

Minimal operating costsmeans the switchgear is practically mainte-nance-free, e.g. contacts of circuit-breakersand disconnectors designed for extremelylong endurance, motor-operated mecha-nisms self-lubricating for life, corrosion-freeenclosure. This ensures that the first in-spection will not be necessary until after25 years of operation.

Reliabilitymeans our overall product concept whichincludes, but is not limited to, the use offinite elements method (FEM), three-dimensional design programs, stereolitho-graphy, and electrical field developmentprograms assures the high standard ofquality.

Smooth and efficientinstallation and commissioningtransport units are fully assembled andtested at the factory and filled with SF6 gasat reduced pressure. Plug connection of allswitches, all of which are motorized, fur-ther improve the speediness of site instal-lation and substantially reduce field wiringerrors.

Routine testsAll measurements are automatically docu-mented and stored in the EDP informationsystem, which enables quick access tomeasured data even if years have passed.

50044

80

5170

All dimensions in mm

Switchgear type 8DN9 8DP3 8DQ1

Details on page 1/10 1/11-1/12 1/13

Bay width [mm] 1200 2200 3600

Rated voltage [kV] up to 145 up to 300 up to 550

Rated power [kV] up to 275 up to 460 up to 740frequencywithstand voltage

Rated lightning [kV] up to 650 up to 1050 up to 1550impulse withstandvoltage

Rated switching [kV] – up to 850 up to 1250impulse withstandvoltage

Rated normal current [A] up to 3150 up to 5000 up to 6300busbars

Rated normal current [A] up to 2500 up to 4000 up to 4000feeder

Rated breaking [kA] up to 40 up to 50 up to 63current

Rated short-time [kA] up to 40 up to 50 up to 63withstand current(1s)

Rated peak [kA] up to 100 up to 135 up to 170withstand current

SF6-gas pressure [bar] up to 4.3 up to 4.0 up to 4.3(gauge) switchgear

SF6-gas pressure [bar] up to 6.0 up to 6.0 up to 6.5(gauge) circuit-breaker

Inspection > 20 years > 20 years > 20 years

5000

3800

3400

3200

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Gas-insulated Switchgear for Substations

SF6-insulated switchgearup to 145 kV, type 8DN9

The clear bay configuration of the light-weight and small 8DN9 switchgear isevident at first sight. Control and monitor-ing facilities are easily accessible in spiteof the compact design of the switchgear.The horizontally arranged circuit-breakerforms the basis of every bay configuration.The operating mechanism is easily acces-sible from the operator area. The other baymodules – of single-phase encapsulateddesign like the circuit-breaker module –are located on top of the circuit-breaker.The three-phase encapsulated passivebusbar is partitioned off from the activeequipment.Thanks to “single-function” assemblies(assignment of just one task to each mod-ule) and the versatile modular structure,even unconventional arrangements can beset up out of a pool of only 20 differentmodules.The modules are connected to each otherby a standard interface which allows anextensive range of bay structures. Theswitchgear design with standardized mod-ules and the scope of services mean thatall kinds of bay structures can be set up ina minimal area.The compact design permits the supply ofdouble bays fully assembled, tested in thefactory and filled with SF6 gas at reducedpressure, which guarantees smooth andefficient installation and commissioning.The following major feeder control levelfunctions are performed in the local controlcabinet for each bay, which is integrated inthe operating front of the 8DN9 switch-gear: Fully interlocked local operation and

state-indication of all switching devicesmanaged reliably by the Siemens digitalswitchgear interlock system

Practical dialogue between the digitalfeeder protection system and centralprocessor of the feeder control system

Visual display of all signals required foroperation and monitoring, together withmeasured values for current, voltage andpower

Protection of all auxiliary current andvoltage transformer circuits

Transmission of all feeder information tothe substation control and protectionsystem

Factory assembly and tests are significantparts of the overall production conceptmentioned above. Two bays at a time un-dergo mechanical and electrical testingwith the aid of computer-controlled stands.

12

3 4

5

12

1011

67

9

1 2 3 4 5 6 7

8

9

10

11

1213

14

15

16

17

1 Busbar I2 Busbar II3 Busbar disconnector I4 Busbar disconnector isolator II5 Grounding switch6 Make-proof grounding switch7 Cable isolator8 Voltage transformer9 Cable sealing end

10 Current transformer11 Grounding switch12 Circuit-breaker13 Hydraulic storage cylinder14 Electrohydraulic operating unit15 Oil tank16 Circuit-breaker control

with gas monitoring unit17 Local control cabinet

Fig. 12: Switchgear bay 8DN9 up to 145 kV

Fig. 13: 8DN9 switchgear for operating voltage 145 kV

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Gas-insulated Switchgear for Substations

SF6-insulated switchgearup to 300 kV, type 8DP3

A switchgear system with entirely individ-ual enclosure of all modules for the three-phase system.Similar to the design concept of the 8DN9switchgear, a horizontally arranged circuit-breaker has been chosen to be the baseunit for the 8DP3 switchgear although theencapsulation is entirely single-phase in-stead of three-phase (busbar). Making useof the experience gained with previous145 kV GIS, the current transformer wasintegrated in the circuit-breaker enclosure.Mounted on top of the circuit-breaker tankare housings containing disconnectors,or grounding switches, or both devices.Depending on the application up to twogrounding switches can be installed inthese enclosures. One grounding switchserves as a work-in-progress groundingdevice for the circuit-breaker, whereas theother external switch may be of the stand-ard slow-moving type or be equipped witha spring-drive mechanism to achieve “faultmaking” capabilities. This feature is oftenrequired at incoming or outgoing feederterminations.The standard design is arranged to accom-modate the double-bus-bar circuits prima-rily used. Naturally all other common circuitrequirements for this voltage level, such asdouble or single bus with bypass and the1 1/2 circuit-breaker arrangement, can befulfilled as well.Care has been taken to design the bussections in such a way that the standardwidth of each bay, including the associatedbusbar section, does not exceed 2.2 m.This solution allows preassembly and test-ing at the factory to a large extent. For ex-ample, a complete 245 kV bay of the GIStype 8DP3 can be shipped pre-tested andonly requiring a minimum amount of instal-lation work on site.Circuit-breaker modules with one inter-rupter unit will meet the requirements foroperating voltages up to 245 kV normally.Voltages above 245 kV, however, as wellas high switching capacities require circuit-breaker units with two interrupter unitsper pole.

1 Busbar disconnector II2 Busbar II3 Busbar disconnector I4 Busbar I5 Grounding switch6 Local control cabinet7 Gas monitoring unit8 Circuit-breaker control unit9 Oil tank

10 Electrohydraulic operating unit11 Hydraulic storage cylinder12 Circuit-breaker13 Current transformer14 Cable sealing end15 Voltage transformer16 Make-proof grounding switch17 Cable disconnector18 Grounding switch

1234

5

6

7 8 9 10 11 12 13

14

15

161718

42

3 1

5

12

1318

16

17

1415

Fig. 15: Complete 8DP3 bay for operating voltage 245 kV being unloaded at site

Fig. 14: Switchgear bay 8DP3 up to 245 kV

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Gas-insulated Switchgear for Substations

1 Busbar disconnector II2 Busbar II3 Busbar disconnector I4 Busbar I5 Grounding switch6 Local control cabinet7 Gas monitoring unit8 Circuit-breaker control unit9 Oil tank

10 Electrohydraulic operating unit11 Hydraulic storage cylinder12 Circuit-breaker13 Current transformer14 Cable sealing end15 Voltage transformer16 Make-proof grounding switch17 Cable disconnector18 Grounding switch

1234

5

6

7 8 9 10 11 12

13

14

15161718

42

3 1

5

12

1318

16

17

1415

Fig. 18: Switchgear bay 8DP3 up to 300 kV

Fig. 16: 8DP3 switchgear for operating voltage 245 kV and 40 kA Fig. 17: 8DP3 switchgear for operating voltage 245 kV and 50 kA

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Gas-insulated Switchgear for Substations

SF6-insulated switchgearup to 550 kV, type 8DQ1

A modular switchgear system for highpower switching stations with individualenclosure of all modules for the three-phase system.The design concept of the 8DQ1 switch-gear follows in principle that of the 8DP3for voltages above 245 kV, i.e. the baseunit for the switchgear forms a horizontallyarranged circuit-breaker on top of whichare mounted the housings containing dis-connectors, grounding switches, currenttransformers, etc. The busbar modules arealso single-phase encapsulated and parti-tioned off from the active equipment.As a matter of course the busbar modulesof this switchgear system are passiveelements, too.Additional main characteristic features ofthe switchgear installation are: Circuit-breakers with two interrupter

units up to operating voltages of 550 kVand breaking currents of 63 kA (from63 kA to 100 kA, circuit-breakers withfour interrupter units have to be con-sidered)

Low switchgear center of gravity bymeans of circuit-breaker arranged hori-zontally in the lower portion

Utilization of the circuit-breaker trans-port frame as supporting device for theentire bay

The use of only a few modules andcombinations of equipment in one enclo-sure reduces the length of sealing facesand consequently lowers the risk ofleakage

10 Grounding switch11 Current transformer12 Cable sealing end13 Local control cabinet14 Gas monitoring unit

(as part of control unit)15 Circuit-breaker control unit16 Electrohydraulic operating unit17 Oil tank18 Hydraulic storage cylinder

1 Busbar disconnector I2 Busbar I3 Busbar II4 Busbar disconnector II5 Grounding switch6 Circuit-breaker7 Voltage transformer8 Make-proof grounding

switch9 Cable disconnector

12 11 10 9 8 7 6 5

4

3

2

1

181716151413

12

23

1 4

5

6

1110

8

9

7

Fig. 19: Switchgear bay 8DQ1 up to 550 kV

Fig. 20: 8DQ1 switchgear for operating voltage 420 kV

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Air con-ditioningsystem

26.90

23.20

Relay room

Groundingresistor

Shuntreactor

13.8 kVswitchgear

15.95

11.50

8.90Cable duct

40 MVA transformer

Radiators

Compensator

2.20

-1.50

Gas-insulatedswitchgear type8DN9

Gas-insulated Switchgear for Substations

Scope of supply andbattery limits

For all types of GIS Siemens suppliesthe following items and observes theseinterface points: Switchgear bay with circuit-breaker inter-

rupters, disconnectors and groundingswitches, instrument transformers, andbusbar housings as specified. For thedifferent feeder types, the following bat-tery limits apply:– Overhead line feeder:

the connecting stud at the SF6-to-airbushing without the line clamp.

– Cable feeder:according to IEC 859 the terminationhousing, conductor coupling, and con-necting plate are part of the GIS deliv-ery, while the cable stress cone withmatching flange is part of the cablesupply (see Fig. 24 on page 1/18).

– Transformer feeder:connecting flange at switchgear bayand connecting bus ducts to trans-former including any compensatorare delivered by Siemens. The SF6-to-oil bushings plus terminal enclo-sures are part of the transformerdelivery, unless agreed otherwise(see Fig. 25 on page 1/18)*.

Each feeder bay is equipped withgrounding pads. The local groundingnetwork and the connections to theswitchgear are in the delivery scopeof the installation contractor.

Initial SF6-gas filling for the entireswitchgear as supplied by Siemens isincluded. All gas interconnections fromthe switchgear bay to the integral gasservice and monitoring panel are sup-plied by Siemens as well.

Hydraulic oil for all circuit-breaker oper-ating mechanisms is supplied with theequipment.

Terminals and circuit protection for aux-iliary drive and control power are pro-vided with the equipment. Feeder cir-cuits and cables, and installation materialfor them are part of the installation con-tractor’s supply.

Local control, monitoring, and interlock-ing panels are supplied for each circuit-breaker bay to form completely oper-ational systems. Terminals for remotemonitoring and control are provided.

Mechanical support structures aboveground are supplied by Siemens; em-bedded steel and foundation work ispart of the installation contractor’s scope.

Fig. 21: Special arrangement for limited space. Sectional view of a building showing the compact nature ofgas-insulated substations

* Note: this interface point should always be closelycoordinated between switchgear manufacturer andtransformer supplier.

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Gas-insulated Switchgear for Substations

Some examples for specialarrangement

Gas-insulated switchgear – usually accom-modated in buildings (as shown in a tower-type substation) – is expedient wheneverthe floor area is very expensive or restrict-ed or whenever ambient conditions neces-sitate their use (Fig. 21).For smaller switching stations, or in casesof expansion when there is no advantagein constructing a building, a favorablesolution is to install the substation in acontainer (Fig. 22).

Mobile containerized switchgear –even for high voltage

At medium-voltage levels, mobile contain-erized switchgear is the state of the art.But even high-voltage switching stationscan be built in this way and economicallyoperated in many applications.The heart is the metal-enclosed SF6-in-sulated switchgear, installed either in asheet-steel container or in a block housemade of prefabricated concrete elements.In contrast to conventional stationaryswitchgear, there is no need for complicat-ed constructions, mobile switching sta-tions have their own ”building“.Mobile containerized switching stationscan be of single or multi-bay design usinga large number of different circuits andarrangements. All the usual connectioncomponents can be employed, such asoutdoor bushings, cable adapter boxes andSF6 tubular connections. If necessary, allthe equipment for control and protectionand for the local supply can be accommo-dated in the container. This allows exten-sively independent operation of the instal-lation on site. Containerized switchgear ispreassembled in the factory and ready foroperation. On site, it is merely necessaryto set up the containers, fit the exteriorsystem parts and make the external con-nections. Shifting the switchgear assemblywork to the factory enhances the qualityand operational reliability. Mobile container-ized switchgear requires little space andusually fits in well with the environment.Rapid availability and short commissioningtimes are additional, significant advantagesfor the operators. Considerable cost re-ductions are achieved in the planning, con-struction work and assembly.

Transformer

-Z1

-Z1

-T1

-00 -052

-T2-T5

-051 -08 -09-Z2

OHL

-Z2

5806

3500

Overhead line

Transformer

-Z2-08-09-T5-T2-052

-00

-T1-051

-Z1

The standard dimensions and ISO cornerfittings will facilitate handling during trans-port in the 20 ft frame of containership andon a low-loader truck.Operating staff can enter the containerthrough two access doors.

GIS up to 300 kV in a container

The 8DP3 switchgear requires a containerwith a length of 7550 mm, a width of2800 mm and a height of 3590 mm.In any case, the container equipment caninclude full thermal insulation, lighting andan air-conditioning and ventilation unit.

Building authority approvals are either notrequired or only in a simple form. The in-stallation can be operated at various loca-tions in succession, and adaptation to localcircumstances is not a problem. These arethe possible applications for containerizedstations: Intermediate solutions for the

modernization of switching stations Low-cost transitional solutions when

tedious formalities are involved in thenew construction of transformer sub-stations, such as in the procurement ofland or establishing cable routes

Quick erection as an emergency stationin the event of malfunctions in existingswitchgear

Switching stations for movable, geo-thermal power plants

145 kV GIS in a standard container

The dimensions of the new 8DN9 switch-gear made it possible to accommodateall active components of the switchgear(circuit-breaker, disconnector, groundingswitch) and the local control cabinet in astandard container.The floor area of 20 ft x 8 ft complieswith the ISO 668 standard. Although thecontainer is higher than the standarddimension of 8 ft, this will not cause anyproblems during transportation as provenby previously supplied equipment.German Lloyd, an approval authority, hasalready issued a test certificate for an evenhigher container construction.

Fig. 22: Containerized 8DN9 switchgear with stub feed in this example

Fig. 23: 8DP3 switching bay being hoisted intoa container

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Gas-insulated Switchgear for Substations

Specification guide formetal-enclosed SF6-insulatedswitchgear

The points below are not considered tobe comprehensive, but are a selection ofthe important ones.

General

These specifications cover the technicaldata applicable to metal-enclosed SF6 gas-insulated switchgear for switching anddistribution of power in cable and/or over-head line systems and at transformers.Key technical data are contained in thedata sheet and the single-line diagramattached to the inquiry.A general “Single-line diagram” and asketch showing the general arrangementof the substation and the transmission lineexist and shall form part of a proposal.The switchgear quoted shall be completeto form a functional, safe and reliable sys-tem after installation, even if certain partsrequired to this end are not specificallycalled for.

Applicable standards

All equipment shall be designed, built,tested and installed to the latest revisionsof the applicable IEC standards (IEC-Publ. 517 “High-voltage metal-enclosedswitchgear for rated voltages of 72.5 kVand above”, IEC-Publ. 129 “Alternatingcurrent disconnectors (isolators) andgrounding switches”, IEC-Publ. 56 “High-voltage alternating-current circuit-break-ers”). IEEE P 468-1 Gas-Insulated Sub-station (GIS) Standards. Other standardsare also met.

Local conditions

The equipment described herein will beinstalled indoors. Suitable lightweight,prefabricated buildings shall be quoted ifavailable from the supplier.Only a flat concrete floor will be providedby the buyer with possible cutouts in caseof cable installation. The switchgear shallbe equipped with adjustable supports(feet). If steel support structures are re-quired for the switchgear, these shall beprovided by the supplier.

For design purposes indoor temperaturesof – 5 °C to +40 °C and outdoor temper-atures of –25 °C to +40 °C shall be consid-ered.For parts to be installed outdoors(overhead line connections) the appli-cable conditions in IEC-Publication 517or IEEE 0468-1 shall also be observed.

Work, material and design

Field welding at the switchgear is notpermitted.Factory welders must be specially qualifiedpersonnel under continuous supervisionof the associated welding society.Material and process specifications neededfor welding must meet the applicable re-quirements of the country of manufacture.Maximum reliability through minimumamount of erection work on site is re-quired. Subassemblies must be erectedand tested in the factory to the maximumextent. The size of the sub-assembliesshall be only limited by the transport con-ditions.The material and thickness of the enclo-sure shall be selected to withstand an in-ternal arc and to prevent a burn-through orpuncturing of the housing within the firststage of protection, referred to a short-circuit current of 40 kA.Normally exterior surfaces of the switch-gear shall not require painting. If done foraesthetic reasons, surfaces shall be appro-priately prepared before painting, i.e. allenclosures are free of grease and blasted.Thereafter the housings shall be paintedwith no particular thickness required but tovisually cover the surface only. The interiorcolor shall be light (white or light grey).In case painted the outside color of theenclosures shall be grey preferably; how-ever, manufacturer’s standard paint color isacceptable. A satin mat finish with a highscratch resistance is preferred.All joints shall be machined and all cast-ings spotfaced for bolt heads, nuts andwashers.Assemblies shall have reliable provisionsto absorb thermal expansion and contrac-tions created by temperature cycling. Forthis purpose metal bellows-type compen-sators shall be installed. They must beprovided with adjustable tensioners.All solid post insulators shall be providedwith ribs (skirts). Horizontally mountedbushings require cleaning openings in theenclosure.

For supervision of the gas within the en-closures, density monitors with electricalcontacts for at least two pressure levelsshall be installed at a central and easilyaccessible location (central gas supervisorycabinet) of each switchgear bay. Thecircuit- breakers, however, might be moni-tored by density gauges fitted in circuit-breaker control units.The manufacturer guarantees that thepressure loss within each individual gascompartment – and not referred to thetotal switchgear installation only – will benot more than 1% per year per gas com-partment.Each gas-filled compartment shall beequipped with static filters of a capacityto absorb any water vapor penetrating intothe switchgear installation over a periodof at least 20 years.Long intervals between the necessary in-spections shall keep the maintenance costto a minimum. A minor inspection shallonly become necessary after ten years anda major inspection preferably after a periodexceeding 20 years of operation unless thepermissible number of operations is metat an earlier date, e.g. 6,000 operations atfull load current or 20 operations at ratedshort-circuit current.

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Gas-insulated Switchgear for Substations

Arrangement and modules

ArrangementThe arrangement shall be single-phaseenclosed preferably.The assembly shall consist of completelyseparate pressurized sections designedto minimize the risk of damage to person-nel or adjacent sections in the event of afailure occurring within the equipment.Rupture diaphragms shall be provided toprevent the enclosures from uncontrolledbursting and suitable deflectors provideprotection for the operating personnel.In order to achieve maximum operatingreliability, no internal relief devices maybe installed because adjacent compart-ments would be affected.Modular design, complete segregation,arc-proof bushings and “plug-in” connec-tion pieces shall allow ready removal ofany section and replacement with mini-mum disturbance of the remaining pres-surized switchgear.

BusbarsAll busbars shall be three-phase or single-phase enclosed and be plug-connectedfrom bay to bay.

Circuit-breakersThe circuit-breaker shall be of the singlepressure (puffer) type with one interrupterper phase*. Heaters for the SF6 gas arenot permitted.The circuit-breaker shall be arranged hori-zontally and the arc chambers and contactsshall be freely accessible.The circuit-breaker shall be designed tominimize switching overvoltages and alsoto be suitable for out-of-phase switching.The specified arc interruption performancemust be consistent over the entire operat-ing range, from line-charging currents tofull short-circuit currents.The complete contact system (fingers,clusters, jets, SF6 gas) shall be designedto withstand at least 20 operations at fullshort-circuit rating without the necessityto open the circuit-breaker for service ormaintenance.The maximum tolerance for phase dis-agreement shall be 3 ms, i.e. until the lastpole has been closed or opened, respec-tively after the first.A highly reliable hydraulic operating mech-anism shall be employed for closing andopening the circuit-breaker. A standard sta-tion battery required for control and trip-ping may also be used for recharging thehydraulic operating mechanism.

The hydraulic storage cylinder will holdsufficient energy for all standard close-open duty cycles.The control system shall provide alarmsignals and internal interlocks, but inhibittripping or closing of the circuit-breakerwhen there is insufficient energy capacityin the hydraulic storage cylinder, or theSF6 density within the circuit-breaker hasdropped below a minimum permissiblelevel.

DisconnectorsAll three-phase isolating switches shall beof the single-break type. DC motor opera-tion (110, 125, 220 or 250 V), completelysuitable for remote operation, and a manu-al emergency drive mechanism is required.Each motor-drive shall be self-containedand equipped with auxiliary switches inaddition to the mechanical indicators.Life lubrication of the bearings is required.

Grounding switchesWork-in-progress grounding switches shallgenerally be provided on either side of thecircuit-breaker. Additional grounding switch-es may be used for the grounding of bussections or other groups of the assembly.DC motor operation (110, 125, 220 or250 V), completely suitable for remoteoperation, and a manual emergency drivemechanism is required.Each motor drive shall be self-containedand equipped with auxiliary positionswitches in addition to the mechanical in-dicators. Life lubrication of the bearingsis required.

High-speed grounding switchesMake-proof high-speed grounding switchesshall generally be installed at cable andoverhead-line terminals. DC motor opera-tion (110, 125, 220 or 250 V), completelysuitable for remote operation, and a manu-al emergency drive mechanism is required.Each motor drive shall be self-containedand equipped with auxiliary positionswitches in addition to the mechanical in-dicators. Life lubrication of the bearingsis required.These switches shall be equipped witha rapid closing mechanism to provide fault-making capability.

Instrument transformersCurrent transformers (C. T.) shall be of thedry-type design not using epoxy resin asinsulation material. Cores shall be providedwith the accuracies and burdens as shownon the SLD. Voltage transformers shall beof the inductive type, with ratings up to200 VA. They shall be foil-gas-insulated andremovable without disturbing the gas com-partment to which they are attached.* two interrupters for voltages exceeding 245 kV

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Gas-insulated Switchgear for Substations

Cable terminations

Single- or three-phase, SF6 gas-insulated,metal-enclosed cable-end housings shallbe provided. The stress cone and suitablesealings to prevent oil or gas from leakinginto the SF6 switchgear are part of thecable manufacturer’s supply. A mating con-nection piece, which has to be fitted to thecable end, will be made available by theswitchgear supplier.The cable end housing shall be suitablefor oil-type, gas-pressure-type and plastic-insulated (PE, PVC, etc.) cables as speci-fied on the SLD, or the data sheets.Facilities to safely isolate a feeder cableand to connect a high-voltage test cableto the switchgear or the cable shall beprovided.

Overhead line terminations

Terminations for the connection of over-head lines shall be supplied completewith SF6-to-air bushings, but without lineclamps.

Fig. 26: Outdoor termination module –High-voltage bushings are used for transition fromSF6-to-air as insulating medium. The bushings can bematched to the particular requirements with regardto arcing and creepage distances. The connectionwith the switchgear is made by means of variable-design angular-type modules.

Control

An electromechanical or solid-state inter-locking control board shall be supplied as astandard for each switchgear bay. This fail-safe interlock system will positively pre-vent maloperations. Mimic diagrams andposition indicators shall give clear demon-stration of the operation to the operatingpersonnel.Provisions for remote control shall besupplied.

Tests required

Partial discharge tests

All solid insulators fitted into the switch-gear shall be subjected to a routine partialdischarge test prior to being installed.No measurable partial discharge is allowedat 1.1 line-to-line voltage (approx. twicethe phase-to-ground voltage). Tolerance:max. 0.4 µV measured at 60 ohms (lessthan 1 pC). This test ensures maximumsafety against insulator failure, good long-term performance and thus a very highdegree of reliability.

Pressure tests

Each enclosure of the switchgear shallbe pressure-tested to at least double theservice pressure, so that the risk of mate-rial defects will be fully excluded.

Leakage tests

Leakage tests are performed on the sub-assemblies shall ensure that the flangesand covers faces are clean, and that theguaranteed leakage rate will not be ex-ceeded.

Power frequency tests

Each assembly shall be subjected to pow-er-frequency withstand tests to verify thecorrect installation of the conductors andalso the fact that the insulator surfaces areclean and the switchgear as a whole is notpolluted inside.

Fig. 25: Transformer/reactor termination module –These termination modules form the direct connec-tion between the GIS and oil-insulated transformersor reactance coils. They can be matched economi-cally to various transformer dimensions by way ofstandardized modules.

Fig. 27: Typical arrangements of bay terminationmodules

Fig. 24: Cable termination module –Cable termination modules conforming to IEC areavailable for connecting the switchgear to high-volt-age cables. The standardized construction of thesemodules allows connection of various cross-sectionsand insulation types. Parallel cable connections forhigher rated currents are also possible using thesame module.

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Gas-insulated Switchgear for Substations

Additional technical data

The supplier shall point out all dimensions,weights and other applicable data of theswitchgear that may affect the local con-ditions and handling of the equipment.Drawings showing the assembly of theswitchgear shall be part of the quotation.

Instructions

Detailed instruction manuals about instal-lation, operation and maintenance of theequipment shall be supplied by the con-tractor in case of an order.

For further information please contact:

Fax: ++ 49-9131-7-346 62

Fig. 30: 8DN9 circuit-breaker operating mechanismwith plug connections of control circuits

Fig. 28: 8DN9 circuit-breaker control cubicle with gasmonitoring devices

Fig. 29: OHL connection of a 420 kV system

Fig. 33: 8DP3 transformer termination modules

Fig. 32: 8DP3 cable termination modules

Fig. 31: Double-bay arrangement of 8DN9 switchgearbeing loaded for transport

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1/20 Siemens Power Engineering Guide · Transmission & Distribution

Gas-insulated Transmission Lines (GIL)

Introduction

For high-power transmission systemswhere overhead lines are not suitable,alternatives are gas-insulated transmissionlines (GIL).The GIL exhibits the following differencesin comparison with cables: High power ratings

(transmission capacity up to 3000 MVAper System)

Suitable for long distances(100 km and more without compensa-tion of reactive power)

High short-circuit withstand capability(including internal arc faults)

Possibility of direct connection to gas-insulated switchgear (GIS) and gas-insu-lated arresters without cable entrancefitting

Multiple earthing points possible Not inflammableThe innovations in the latest Siemens GILdevelopment are the considerable reduc-tion of costs and the introduction of buriedlaying technique for GIL for long-distancepower transmission.SF6 has been replaced by a gas mixtureof SF6 and N2 as insulating medium.

Siemens experience

Back in the 1960s with the introduction ofsulphur hexafluoride (SF6) as an insulatingand switching gas, the basis was found forthe development of gas-insulated switch-gear (GIS).On the basis of GIS experience, Siemensdeveloped SF6 gas-insulated lines to trans-mit electrical energy too. In the early 1970sinitial projects were planned and imple-mented. Such gas-insulated lines wereusually used within substations as busbarsor bus ducts to connect gas-insulatedswitchgear with overhead lines, the aimbeing to reduce clearances in comparisonto air-insulated overhead lines.Implemented projects include GIL laying intunnels, in sloping galleries, in verticalshafts and in open air installation.Flanging as well as welding has been ap-plied as jointing technique.

The gas-insulated transmission line tech-nique has proved a highly reliable systemin terms of mechanical and electrical fail-ures. Once a system is commissioned andin service, it can run reliably without anydielectrical or mechanical failures reportedover the course of 20 years. For example,one particular Siemens GIL will not under-go its scheduled inspection after 20 yearsof service, as there has been no indicationof any weak point.Fig. 34 shows the arrangement of sixphases in a tunnel.

Fig. 34: GIL arrangement in the tunnel of the Wehr pumped storage station(4000 m length, in service since 1975)

Fig. 35: Siemens lab prototype for dielectric tests

Basic design

In order to meet mechanical stability crite-ria, gas-insulated lines need minimumcross-sections of enclosure and conductor.With these minimum cross-sections, highpower transmission ratings are given.Due to the gas as insulating medium, lowcapacitive loads are assured so that com-pensation of reactive power is not needed,even for long distances of 100 km andmore.

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Gas-insulated Transmission Lines (GIL)

Several development tests have been car-ried out in Siemens test labs as well as incooperation with the French utility compa-ny Electricité de France (EDF). Dielectrictests have been undertaken on a lab proto-type as shown in Fig. 35.Results of these investigations show thatthe bulk of the insulating gas for industrialprojects involving a considerable amountof such a substance should be nitrogen,a nontoxic natural gas.

Reduction of SF6 content

However, another insulating gas should beadded to nitrogen in order to improve theinsulating capability and to minimize sizeand pressure. A N2/SF6 gas mixture withhigh nitrogen content (and sulphur hexa-fluoride portion as low as possible) wasfinally chosen as insulating medium.To determine the percentage of SF6 anoptimization process was needed to findthe best possible ratio between SF6 con-tent, gas pressure and enclosure diameter.The basic behaviour of N2/SF6 gas mixturesshows that with an SF6 content of only15–25%, an insulating capability of 70–80%of pure SF6 can be attained at the samegas pressure.The technical data of the GIL are shown inFig. 36.

Jointing technique

In order to improve the gas-tightnessand to facilitate laying, flanges have beenavoided as jointing technique. Instead,welding has been chosen to join the vari-ous GIL construction units.The welding process is highly automated,with the use of an orbital welding machineto ensure high quality of the joints. Thisorbital welding machine contributes tohigh productivity in the welding processand therefore speeds up laying. The relia-bility of the welding process is controlledby an integrated computerized qualityassurance system.

Anti-corrosion protection

Directly buried gas-insulated transmissionlines will be safeguarded by a passive andactive corrosion protection system. Thepassive corrosion protection system com-prises a PE or PP coating and assures atleast 40 years of protection. The activecorrosion protection system provides pro-tection potential in relation to the alumi-num sheath. An important requirementtaken into account is the situation of anearth fault with a high current of up to63 kA to earth.

Laying

The most recently developed SiemensGILs are scheduled for directly buriedlaying.The laying technique must be as compat-ible as possible with the landscape andmust take account of the sequence of

Fig. 37: GIL laying technique

seasons. The laying techniques for pipe-lines have been developed over manyyears and have proved reliable. The high-voltage gas-insulated transmission lineneeds special treatment where the pipe-line technique has to be adapted.The laying process is illustrated in Fig. 37.The assembly area needs to be protectedagainst dust, particles, humidity and otherenvironmental factors that might disturbthe dielectric system. Clean assemblytherefore plays a major role in setting upcross-country GILs under normal environ-mental conditions. The combination ofclean assembly and productivity is en-hanced by a high level of automation ofthe overall process. A clean assemblytent is essential.

References

Siemens has gathered experience withgas-insulated transmission lines at ratedvoltages of up to 550 kV and with systemlengths totalling more than 30 km.The first GIL stretch built by Siemens isthe connection of the turbine generator/pumping motor of a pumped storagestation with the switchyard. The 420 kVGIL is laid in a tunnel through a mountainand has a length of 4000 m (Fig. 34). Thisconnection was commissioned in 1975 atthe Wehr pumped storage station in theBlack Forest in Southern Germany.

For further information please contact:

Fax ++ 49-9131-7-34490

Fig. 36: GIL technical data

Technical data

up to 550 kV

2000–4600 A

1500–3000 MVA

2.2*lr for 10 min.

1.9*lr for 1 h

≈ 60 nF/km

1–100 km

10%/90%up to35%/65%

directly buried

in tunnels/sloping galleries/vertical shafts

open air installation

Rated voltage

Rated current lr

Transmissioncapacity

Overload capacity

Capacitance

Typical length

Gas mixture SF6/N2ranging from

Laying

P/M

CD

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1/22 Siemens Power Engineering Guide · Transmission & Distribution

Circuit Breakers for 72 kV up to 800 kV

Introduction

Circuit breakers are the main module ofboth AIS and GIS switchgear. They have tomeet high requirements in terms of: Reliable opening and closing Consistent quenching performance with

rated and short-circuit currents evenafter many switching operations

High-performance, reliable maintenance-free operating mechanisms.

Technology reflecting the latest state ofthe art and years of operating experienceare put to use in constant further develop-ment and optimization of Siemens circuitbreakers. This makes Siemens circuitbreakers able to meet all the demandsplaced on high-voltage switchgear.The comprehensive quality system,ISO 9001 certified, covers development,manufacture, sales, installation and after-sales service. Test laboratories are accred-ited to EN 45001 and PEHLA/STL.

Main construction elements

Each circuit breaker bay for gas-insulatedswitchgear includes the full complementof isolator switches, grounding switches(regular or proven), instrument transform-ers, control and protection equipment, in-terlocking and monitoring facilities, com-monly used for this type of installation(See chapter GIS, page 1/8 and following).Circuit breakers for air-insulated switch-gear are individual components and areassembled together with all individualelectrical and mechanical components ofan AIS installation on site.All Siemens circuit breaker types, whetherair- or gas-insulated, consist of the samecomponents of a parts family, i.e.: Interrupter unit Operating mechanism Sealing system Operating rod Control elements.

SF6-insulated circuit breakers

Controlelements

Interrupterunits

Operatingmechanism

Sealing systems

Parts family

Fig. 38: Circuit breaker parts family

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Circuit Breakers for 72 kV up to 800 kV

The blast cylinder (4) encloses the arc-quenching arrangement like a pressurechamber. The compressed SF6 flows ra-dially into the break by the shortest routeand is discharged axially through the noz-zles (6). After arc extinction, the contacttube (3) moves into the open position.In the final position, handling of test volt-ages in accordance with IEC and ANSI isfully guaranteed, even after a number ofshort-circuit switching operations.

Major features

Erosion-resistant graphite nozzles Consistently high dielectric strength Consistent quenching capability across

the entire performance range High number of short-circuit breaking

operations High levels of availability Long maintenance intervals.

The operating mechanism

The operating mechanism is a centralmodule of the high-voltage circuit breakers.Two different mechanism families are avail-able for Siemens circuit breakers: Electrohydraulic mechanism for all

AIS and GIS types Spring-stored energy mechanism for

AIS types up to 170 kV.

The electrohydraulic operating mechanism

All hydraulically operated Siemens circuitbreakers have a uniform operating mecha-nism concept, whether for 72 kV circuitbreakers with one interrupter unit per poleor breakers from the 800 kV level with fourinterrupter units per pole. Identical operat-ing mechanisms (modules) are used forsingle or triple-pole switching of outdoorcircuit breakers.The electrohydraulic operating mecha-nisms have proved their worth all over theworld. The power reserves are ample, theswitching speed is high and the storagecapacity substantial. The working capacityis indicated by the permanent self-monitor-ing system.

The interrupter unit

Current-path assembly

The conducting path is made up of theterminal plates (1 and 7), the fixed tubes(2) and the spring-loaded contact fingersarranged in a ring in the moving contacttube (3).

Arc-quenching assembly

The fixed tubes (2) are connected bythe contact tube (3) when the breaker isclosed. The contact tube (3) is rigidly cou-pled to the blast cylinder (4), the two to-gether with a fixed annular piston (5) inbetween forming the moving part of thebreak chamber. The moving part is drivenby an operating rod (8) to the effect thatthe SF6 pressure between the piston (5)and the blast cylinder (4) increases.When the contacts separate, the movingcontact tube (3), which acts as a shutoffvalve, releases the SF6. An arc is drawnbetween one nozzle (6) and the contacttube (3). It is driven in a matter of millisec-onds between the nozzles (6) by the gasjet and its own electrodynamic forces andis safely extinguished.

1

2

36

4

5

2

8

7

Arc

Breaker inclosed position

Precompression Gas flow duringarc quenching

Breaker inopen position

Upper terminalplateFixed tubesMoving contacttubeBlast cylinderBlast pistonArc-quenchingnozzlesLower terminalplateOperating rod

1

23

456

7

8

Fig. 39: The interrupter unit

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Circuit Breakers for 72 kV up to 800 kV

The force required to move the piston andpiston rod is provided by differential oilpressure inside a sealed system. A hydrau-lic storage cylinder filled with compressednitrogen provides the necessary energy.Electromagnetic valves control the oil flowbetween the high- and low-pressure sidein the form of a closed circuit.

Main features:

Plenty of operating energy Long switching sequences Reliable check of energy reserves

at any time Switching positions are reliably

maintained, even when the auxiliarysupply fails

Excessive strong foundations Low-noise switching No oil-leakage and consequently

environmentally compatible Maintenancefree.

Description of function

Closing:The hydraulic valve is opened by elec-tromagnetic means. Pressure from thehydraulic storage cylinder is therebyapplied to the piston with two differentsurface areas. The breaker is closed viacouplers and operating rods moved bythe force which acts on the larger sur-face of the piston. The operating mech-anism is designed to ensure that, in theevent of a pressure loss, the breakerremains in the particular position.

Tripping:The hydraulic valve is changed overelectromagnetically, thus relieving thelarger piston surface of pressure andcausing the piston to move onto theOFF position. The breaker is ready forinstant operation because the smallerpiston surface is under constant pres-sure. Two electrically separate trippingcircuits are available for changing thevalve over for tripping.

M

P P

M

Oil tank

Hydraulic storagecylinder

Operating cylinder

Releases

Operating piston

Pilot control

On Off

N2

Main valve

Auxiliaryswitch

Monitoring unitand hydraulic

pump with motor PP

Fig. 43: Schematic diagram of a Q-range operating mechanism

Fig. 40: Operating unit of the Q-range AIS circuitbreakers

Fig. 42: Operating cylinder with valve block andmagnetic releases

Fig. 41: Q-range operating unit for GIS circuitbreaker 8DN9

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Circuit Breakers for 72 kV up to 800 kV

The spring-stored energyoperating mechanism

Optional to the hydraulic operating mecha-nism, Siemens circuit breakers for voltagesup to 170 kV can be equipped with spring-stored energy operating mechanisms.These drives are based on the same prin-ciple, which has been proving its worth inSiemens low and medium voltage circuitbreakers for decades. The design is simpleand robust with few moving parts and avibration-isolated latch system of highestreliability. All components of the operatingmechanism, the control and monitoringequipment and all terminal blocks arearranged compact and yet clear in onecabinet.Depending on the design of the operat-ing mechanism, the energy required forswitching is provided by individual com-pression springs (i.e. one per pole) or bysprings that function jointly on a triple-polebasis.The principle of the operating mechanismwith charging gear and latching is identicalon all types. The differences betweenmechanism types are in the number, sizeand arrangement of the opening and clos-ing springs.

Major features at a glance

Uncomplicated, robust constructionwith few moving parts

Maintenancefree Vibration-isolated latches Load-free uncoupling of charging

mechanism Ease of access 10,000 operating cycles

1234567

89

10111213141516

1718

Corner gearsCoupling linkageOperating rodClosing releaseCam plateCharging shaftClosing springconnecting rodClosing springHand-wound mechanismCharging mechanismRoller levelClosing damperOperating shaftOpening damperOpening releaseOpening springconnecting rodMechanism housingOpening spring

1

2

3

4

5

6

7

818

17

1615

14

1312

11

10

9

Fig. 44

Fig. 45: Combined operating mechanism and monitoring cabinet

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Circuit Breakers for 72 kV up to 800 kV

Circuit breakersfor air-insulated switchgearstandard live-tank breakers

The construction

All circuit breakers are of the same generaldesign, as shown in the illustrations. Theyconsist of the following main components:1) Interrupter unit2) Closing resistor (if applicable)3) Operating mechanism4) Insulator column (AIS)5) Operating rod6) Breaker base7) Control unitThe simple design of the breakers andthe use of many similar components, suchas interrupter units, operating rods andcontrol cabinets, ensure high reliability be-cause the experience of many breakersin service could be used for the improve-ment of the design. The interrupter unitfor example has proven its reliability inmore than 60,000 units all over the world.The control unit includes all necessarydevices for circuit-breaker control and mon-itoring, such as: Pressure/SF6 density monitors Gauges for SF6 and hydraulic pressure

(if applicable) Relays for alarms and lockout Antipumping devices Operation counters (upon request) Local breaker control (upon request) Anticondensation heaters.

Transport, installation and commissioningare performed with expertise and effi-ciency.The tested circuit breaker is shipped inthe form of a small number of compactunits. If desired, Siemens can provideappropriately qualified personnel for instal-lation and commissioning.

Fig. 46: 145 kV circuit breaker 3AQ1FG with triple-polespring stored-energy operating mechanism

Fig. 47: 800 kV circuit breaker 3AT5

Fig. 48: 245 kV circuit breaker 3AQ2

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Circuit Breakers for 72 kV up to 800 kV

1 Interrupter unit2 Arc-quenching nozzles3 Moving contact4 Filter5 Blast cylinder6 Blast piston7 Insulator column8 Operating rod9 Hydraulic operating mechanism10 Control unit11 SF6 density monitor

1

2

3

4

56

7

8

910 11

Fig. 50: Type 3AQ1-E

1 Interrupter unit2 Arc-quenching nozzles3 Moving contact4 Filter5 Blast piston6 Blast cylinder7 Bell-crank mechanism8 Insulator column9 Operating rod10 Hydraulic operating mechanism11 ON/OFF indicator12 Oil tank13 Control unit

12

9

8

10114

13

653721

1 Interrupter unit2 Closing resistor3 Valve unit4 Electrohydraulic

operatingmechanism

5 Insulator columns6 Breaker base7 Control unit

1

5

3

4

7

6

2

Fig. 49: Type 3AT4/5

Fig. 51: Type 3AQ2

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Circuit Breakers for 72 kV up to 800 kV

d

h

d

h

Type 3AP1/3AQ1

72.5 123 145 170 2451

Spring-stored-energy/Electrohydraulic

140 230 275 325 460

325 550 650 750 1050

For rated voltage < 300 kV, no tests with switching impulse withstand voltage prescribed4000 4000 4000 4000 400040 40 40 40/50 50100 100 100 100/125 125

Triple-pole or single- and triple-pole 3 cycles (3AP/3AQ)

48…250= or ~120…240 V/50 Hz, 120…280 V/60 Hz48…250 V=

700 1250 1250 1500 22001813 3625 3625 4250 61501350 1500 1500 2000 3000660 660 660 1280 12803810 4360 4360 4065 5485

25 years or 6000 operating cycles

Electrical data

Rated voltageInterrupter units per poleType of operating mechanismStandardsRated power frequencywithstand voltage 1 min [kV]Rated lightning impulsewithstand voltage 1.2/50 µs [kV]Switching impulsewithstand voltage 250/2500 µs [kV]Rated current up to [A]Rated-short-time current (1–3 s) [kA]Rated peak withstand current [kA]AutoreclosureBreak time 3AP/3AQ

3ATRated duty cycleAuxiliary power supply foroperating mechanism motorControl voltages

Basic design

Minimum striking distance [mm]Minimum creepage distance [mm]Circuit breaker weight approx. [kg]Main dimensions: Depth d [mm]

Height h [mm]

Maintenance

Inspection due after

Fig. 52: Product range/ratings

The values stated are nominal (VDE, IEC). Other values on request.

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d

h

d

h

3AQ2/3AT2/3AT3* 3AT4/3AT5*

245 300 362 420 550 362 420 550 765/8002 4

Electrohydraulic Electrohydraulic DIN VDE, IEC, ANSI

460 435 520 610 800 450/520 520/610 620/760 830/1100

1050 1050 1175 1425 1550 1175 1425 1550 2100

850 950 1050 1175 950 1050 1175 1425/15504000 4000 4000 4000 4000 4000 4000 4000 400050/80 50/63 50/63 50/63 50/63 80 80 80 63125/200 125/160 125/160 125/160 125/160 200 200 200 160

Single- and triple-pole

2cycles (3AT)O-0,3 sec-CO-3 min-CO or CO-15 sec-CO

48…250 V= or ~ 280/120…500/29848…250 V=

2200 2750/2200 2750/2200 3300 3800 2700 3300 3800 50006150/6050 7875/6050 7875/7165 10375/9075 13750 7165 9075 10190 138603600/5980 4390/6430 5010/9090 5500/8600 12500 14400 14700 19200 234002995/4060 3895/4025 3695/4280 4195/4280 5135 6830 6830 7505 90603790/4490 4385/4490 4400/9300 10500/10100 13690 4990 6000 6550 8400

25/20 years or 6000 operating cycles 20 years or 6000 operating cycles

Circuit Breakers for 72 kV up to 800 kV

* with closing resistor

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Circuit Breakers for 72 kV up to 800 kV

Circuit breakersin dead-tank design

For certain substation designs, dead-tankcircuit breakers might be required insteadof the standard live-tank breakers. Forthese purposes Siemens can offer thedead-tank circuit breaker types.

Main features at a glance

Reliable opening and closing

Proven contact and arc-quenchingsystem

Consistent quenching performancewith rated and short-circuit currentseven after many switching operations

Similar uncomplicated design for allvoltages

High performance, reliable operatingmechanisms

Easy-to-actuate spring operatingmechanisms

Hydraulic operating mechanisms withon-line monitoring

Economy

Perfect finish Simplified, quick installation process Long maintenance intervals High number of operating cycles Long service life

Individual service

Close proximity to the customer Order specific documentation Solutions tailored to specific problems After-sales service available promptly

worldwide

The right qualifications

Expertise in all power supply matters 30 years of experience with SF6-insulat-

ed circuit breakers A quality system certified to ISO 9001,

covering development, manufacture,sales, installation and after-sales service

Test laboratories accredited to EN 45001and PEHLA/STL

Fig. 53: SPS-circuit breaker 145 kV

Subtransmission breaker

Type SPS power circuit breakers are de-signed as general, definite-purpose break-ers for application at maximum rated volt-ages of 121 and 145 kV. Rated interruptingcapacities are 20, 25, 31.5 or 40 kA. Con-tinuous current ratings are up to 3000 A(Fig. 53).

Bushings Current transformers

Interrupters

Control cabinetand SE-4 springmechanism

Base legs

Pressuregauges

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Circuit Breakers for 72 kV up to 800 kV

Transmission class puffer

Type TCP (transmission class puffer)breakers are designed as general, definite-purpose breakers for application at maxi-mum rated voltages of 121, 145, 169 and242 kV. Rated interrupting capacities forthe 121 and 145 kV breakers are 20, 25,31.5, 40 or 50 kA. The 169 and 242 kVunits have interrupting ratings of up to60 kA. Continuous current ratings are upto 3000 A.The breakers are designed and tested tomeet ANSI, IEEE, NEMA, IEC standards(Fig. 54/55).

Features are:

Dead-tank construction State-of-the-art interrupter design Extension of the high quality, reliable

SP-72.5 breaker SE-4 spring mechanism Light weight, simple design Porcelain bushings Bushing current transformers

(space for 3 per bushing) Low operating pressure Tested and verified for seismic appli-

cation Minimal noise 40 °C/–50 °C application Shipped fully assembled.

Savings in installation

Factory preassembly, testing and timingwith no internal field adjustments

Minimal gas handling. Shipped with0.5 bar positive pressure

Minimal transportation and equipmenthandling. Truck shipment to site

Easy access for final wiring Negligible foundation loading Location of control cabinet allows for

easy, direct breaker replacement forsystem upratings

Compact design allows use of existingfoundations.

Fig. 54: TCP-circuit breaker 145 kV

Fig. 55: SP-circuit breaker 72.5 kV

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Circuit Breakers for 72 kV up to 800 kV

The construction

The type SPS breaker consists of threeidentical pole units mounted on a commonsupport frame. The opening and closingforce of the SE-4 spring operating mecha-nism is transferred to the moving contactsof the interrupter through a system of con-necting rods and a rotating seal at the sideof each phase.The tanks and the porcelain bushingsare charged with SF6 gas at a nominalpressure of 5.5 bar. The SF6 serves as bothinsulation and arc-quenching medium.A control cabinet mounted at one endof the breaker houses the spring operatingmechanism and breaker control compo-nents.Interrupters are located in the aluminumhousings of each pole unit. The interrupt-ers use the latest Siemens puffer arc-quenching system.The spring operating mechanism is thesame design as used with the SiemensSP breakers. This design has been in ser-vice for years, and has a well documentedreliability record.Customers can specify up to four (in somecases, up to six) bushing type currenttransformers (CT) per phase. These CTs,mounted externally on the aluminum hous-ings, can be removed without disturbingthe bushings.

Operating mechanism

The type SE-4 mechanically and electricallytripfree spring mechanism is used on typeSPS breakers. The type SE-4 closing andopening springs hold a charge for storing”open-close-open“ operations (Fig. 56).A weatherproof control cabinet has a largedoor, sealed with rubber gaskets, for easyaccess during inspection and maintenance.Anticondensation units (475 W) offer con-tinuous inside/outside temperature differ-ential for prevention of condensation.

SF6 monitoringequipment

Transformerterminal blocks

Control terminalblocks

Auxiliaryswitch

Closingmechanism

Controlpanel Closing spring Motor

Fig. 56: Operating mechanism

Included in the control cabinet are neces-sary auxiliary switches, cutoff switch, latchcheck switch, alarm switch and operationcounter. The control relays and three con-trol knife switches (one each for the con-trol, heater and motor) are mounted on acontrol panel. Terminal blocks on the sideand rear of the housing are available forcontrol and transformer wiring.The SE-4 is ideally suited for high-speedreclosing. Reclosing speeds of 10 cyclesfrom the instant of initial tripping impulseuntil the current is reestablished are com-mon.

For further information please contact:

Fax: ++49 -303 86 -2 5867

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Circuit Breakers for 72 kV up to 800 kV

The new 3AT2/3-DTCircuit Breaker

Composite insulators

The new 3AT2/3-DT is available with bush-ings made from composite insulators –this has many practical advantages.The SIMOTEC® composite insulators man-ufactured by Siemens consist of a basicbody made of epoxy resin reinforced glassfibre tubes. The external tube surface iscoated with vulcanised silicone. As is thecase with porcelain insulators, the externalshape of the insulator has a multishedprofile. Field grading is implemented bymeans of a specially shaped screeningelectrode in the lower part of the compos-ite insulator.The bushings and the metal tank of thecircuit breaker surround a common gasvolume. The composite insulator used onthe bushing of the 3AT2/3-DT is a one-piece insulating unit. Compared with con-ventional housings, composite insulatorsoffer a wide range of advantages in termsof economy, efficiency and safety.

Interrupter unit

The 3AT2/3-DT pole consists of two break-ing units in series impressive in the sheersimplicity of their design. The tried andtested Siemens contact system with dou-ble graphite nozzles guarantees faultlessoperation, consistently high arc-quenchingcapacity and a long operating life, even athigh switching frequencies. Thanks to con-stant further development, optimisationand consistent quality assurance, Siemensarc-quencing systems meet all the require-ments placed on modern high voltagetechnology.

Hydraulic Drive

The operating energy required for the3AT2/3-DT interrupters is provided by thehydraulic drive, which is manufactured in-house by Siemens. The functional principleof the hydraulic drive constitutes a techni-cally clear solution which offers certainfundamental advantages.Hydraulic drives provide high amounts ofenergy economically and reliably. In thisway, even the most demanding switchingrequirements can be mastered in shortopening times.

Fig. 57: The new 3AT2/3-DT circuit breaker with SIMOTEC composite insulator bushings

Siemens hydraulic drives are maintenance-free and have a particulary long operatinglife. They meet the strictest criteria forenviromental acceptability. In this respect,too, Siemens hydraulic drives have proventhemselves through decades of operation.

For further information please contact:

Fax: ++ 49- 30386- 258 67

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1/34 Siemens Power Engineering Guide · Transmission & Distribution

Circuit Breakers for 72 kV up to 800 kV

Fig. 58: Product range/ratings

Electrical data

Rated voltage [kV]

Interrupter units per pole

Type of operating mechanism

Standards

Rated power frequencywithstand voltage 1 min [kV]

Rated lightning impulsewithstand voltage 1.2/50 µs [kV]

Rated current up to [A]

Rated-short-time current (1–3 s) [kA]Rated peak withstand current [kA]

Autoreclosure

Break time [cycles]

Rated duty cycle

Auxiliary power supply foroperating mechanism motor

Control voltages

Basic design

Minimum striking distance [mm]

Minimum creepage distance [mm]

Circuit breaker weight approx. [kg]

Main dimensions: Depth d [mm]Height h [mm]

Maintenance

Inspection due after

Type SP/SPS* SPS

72.5 121 145

1 1 1

Spring-stored-energy

ANSI/IEEE/NEMA/IEC

160 260 310

350 550 650

3000 3000 3000

20/31.5/40 20/25/31.5/40 20/25/31.5/4054/85/108 54/67/85/108 54/67/85/108

Triple-pole

3 3 3

O-CO-15 s-CO

250/125 VDC or 110/230 VAC single-phase

125/250 VDC

480 (730) 1160 1160

1280 (1850) 2360 2360

1750 3250 3250

1600 (2400) 2100 21003330 (3500) 2780 2780

6 years/2000 operating cycles

* The design of these breakers is slightly different. For details please inquire.

d

h

h

d

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1/35Siemens Power Engineering Guide · Transmission & Distribution

Circuit Breakers for 72 kV up to 800 kV

TCP* 3AT2/3-DT

121 145 169 242 550

1 1 1 1 2

Electrohydraulic Hydraulic

ANSI/IEEE/NEMA/IEC ANSI/IEC

260 310 365 425 860

550 650 750 900 1800

3000 3000 3000 3000 4000

20/31.5/40/50 20/31.5/40/50/63 6354/85/108/135 54/85/108/135/170 170

Triple-pole Single- and triple-pole

3 3 3 3 2

O-CO-15 s-CO O-0.3 s-CO-3 s-CO or CO-15 s-O

250/125 VDC or 110/230 VAC single-phase 60…250 VDC or 120…380 VAC

125/250 VDC 60…250 VDC

1190 1190 1620 1620 4460

2330 2330 3550 3550 11000

4300 4300 5500 5500 21800

2330 2330 2590 2590 2250 (single-pole)4036 4036 4780 4780 8440

25 years

h

d

h

d

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1/36 Siemens Power Engineering Guide · Transmission & Distribution

High-voltage Direct Current Transmission

Fig. 61: Long-distance transmission

Special features

Valve technology

Simple, easy-to-maintain mechanicaldesign

Use of fire-retardant, self-extinguish-ing material

Minimized number of electricalconnections

Minimized number of components Avoidance of potential sources of

failure ”Parallel“ cooling for the valve levels Oxygen-saturated cooling water.After about 20 years of operation thevalves have demonstrated the superiorityof these design criteria as well as excellentreliability.

Control system

High-performance standard system withmany applications in different fields.Use of ”state-of-the-art“ microprocessorsystems for all functions.Redundant design for fault-tolerantsystems.

Filter technology

Single-, double- and triple-tuned as wellas high-pass passive filters, or any combi-nation thereof, can be installed.Active filters, mainly for the DC circuit,are available.Wherever possible, identical filters areselected so that the performance does notsignificantly change when one filter hasto be switched off.

HVDC

Where AC technology reaches its limits,DC expands the possibilities, e.g.

For economic transmission of bulkpower over long distances

For power across the sea over adistance of ≈ 50 km

For the connection of asynchronouspower grid systems

For the connection of synchronous butweak power grid systems

For additional active power exchangewithout increasing the short-circuitpower

For the increase of transmission capacityon existing rights-of-way.

Siemens offers HVDC systems as Back-to-Back (B/B) Cable Transmission (CT) and Long-distance Transmission Systems

(LD).

Back-to-Back (B/B):

To connect asynchronous high voltagepower systems or systems with differentfrequencies.To stabilize weak AC links or to supplyeven more active power, where the ACsystem reaches the short-circuit capability.

Cable transmission (CT):

To transmit power across the sea withcables to supply islands/offshore platformsfrom the mainland and vice versa.

Long-distance transmission (LD):

To transmit bulk power over longdistances, e.g. 1000 km and more.

Turnkey service

Experienced staff is prepared to designand install the whole HVDC system ona trurnkey basis and ready for operation.Siemens is also able to assist in findinga proper project financing.

General services

Studies for: System dynamic response Load flow and reactive power balance HVDC system basic design Interference of radio and PLC Harmonic voltage distorsion Insulation coordination Assistance for drafting the specification Maintenance Upgrading/replacement of components/

redesign for older schemes, e.g. mer-cury-arc valves or relay-based controls

General support from the very beginningof a HVDC planning to assistance duringoperation.

Typical values

Typical values are found in but not limitedto the following ranges:B/B: 100 ... 600 MWCT: 100 ... 800 MWLD: 300 ... 3000 MW (bipolar)Where the lower value is mainly deter-mined by economic aspects and the uppervalue is limited by the constraints of theconnected networks.

Fig. 62: Earthquakeproof, fire-retardent thyristor valves in Sylmar East, Los Angeles, CA

Fig. 59: Interconnected system operation

Fig. 60: Cable transmission

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1/37Siemens Power Engineering Guide · Transmission & Distribution

High-voltage Direct Current Transmission

Fig. 64: Man-machine Interface with structure of HVDC control system

Higher availability means more operatinghours, better utilization and higher profitsfor the owner.The new Man-Machine Interface (MMI)system enhances the user friendliness andincreases the reliability considerably dueto the operator guidance. This excludes amaloperation by the operator, because anincorrect command will be ignored by theMMI.

For further information please contact:

Fax: ++49- 9131-73 35 66

Rehabilitation andmodernization of existingHVDC stations

The integration of state-of-the-art micro-processor systems or thyristors allows theowner better utilization of his investment,e.g. Higher availability Fewer outages Fewer losses Better performance values Less maintenance.

SER

MMI

VCSPole 1

OLCPole 1

OLCSC

OLCPole 2

VCSPole 2

LAN

CLCVBEPole 1

CLCVBEPole 2

OLCPole 2

TFRTFR

DC Yard

DC Protection

Communi-cation link tothe load dis-patch center

Communi-cation link tothe remotestation

GPS

Communi-cation link tothe remotestation

MMI Man-machine InterfaceGPS Global Positioning SystemOLC Open Loop ControlCLC Closed Loop ControlVBE Valve Base ElectronicsVCS Valve Cooling SystemsSER Sequence of Event

RecordingTFR Transient Fault RecordingLAN Local Area Network

Fig. 63: HVDC outdoor valves, 533 kV

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1/38 Siemens Power Engineering Guide · Transmission & Distribution

Power Compensation in Transmission Systems

1 Transformer2 Thyristo-controlled reactor (TCR)3 Fixed connected capacitor/filter bank4 Thyristor-switched capacitor bank

(TSC)

3442

1

Voltage controlReactive power controlOvervoltage limitation at load rejectionImprovement of AC-system stabilityDamping of power oscillationsReactive power flow controlIncrease of transmission capabilityLoad reduction by voltage reductionSubsynchronous oscillation damping

Types of reactive powercompensation

Parallel compensation

Parallel compensation is defined as anytype of reactive power compensation em-ploying either switched or controlled units,which are connected parallel to the trans-mission network at a power system node.In many cases switched compensation(reactors, capacitor banks or filters) canprovide an economical solution for reactivepower compensation using conventionalswitchgear.

In comparison to mechanically-switchedreactive power compensation, controlledcompensation (SVC, Fig. 65) offers the ad-vantage that rapid dynamic control of thereactive power is possible within narrowlimits, thus maintaining reactive powerbalance.Fig. 66 is a general outline of the problem-solving applications of SVCs in high-volt-age systems.

Series compensation

Series compensation is defined as inser-tion of reactive power elements into trans-mission lines. The most common applica-tion is the series capactior.By providing continuous control of trans-mission line impendance, the AdvancedSeries Compensation (ASC, Fig. 67)scheme offers several advantages toconventional fixed series capacitor instal-lations. These advantages include continu-ous control of the desired compensationlevel, direct smooth control of power flowwithin the network and improved capaci-tor-bank protection.

Introduction

In many countries increasing powerconsumption leads to growing and moreinterconnected AC power systems. Thesecomplex systems consist of all types ofelectrical equipment, such as power plants,transmission lines, switchgear transform-ers, cables etc., and the consumers.Since power is often generated in thoseareas of a country with little demand, thetransmission and distribution system hasto provide the link between power gener-ation and load centers.Wherever power is to be transported, thesame basic requirements apply: Power transmission must be economical The risk of power system failure must

be low The quality of the power supply must

be highHowever, transmission systems do notbehave in an ideal manner. The systemsreact dynamically to changes in active andreactive power, influencing the magnitudeand profile of the power systems voltage.

Examples:

A load rejection at the end of a long-dis-tance transmission line will cause highovervoltages at the line end. However, ahigh load flow across the same line willdecrease the voltage at its end.

The transport of reactive power througha grid system produces additional lossesand limits the transmission of activepower via overhead lines or cables.

Load-flow distribution on parallel lines isoften a problem. One line could be load-ed up to its limit, while another only car-ries half or less of the rated current.Such operating conditions limit the actu-al transmittable amount of active power.

In some systems load switching and/orload rejection can lead to power swingswhich, if not instantaneously damped,can destabilize the complete grid systemand then result in a “Black Out”.

Reactive power compensation helps toavoid these and some other problems.In order to find the best solution for a gridsystem problem, studies have to be car-ried out simulating the behavior of the sys-tem during normal and continuous operat-ing conditions, and also for transientevents. Study facilities which cover digitalsimulations via computer as well as analogones in a transient network analyser labo-ratory are available at Siemens.

Fig. 67: Advanced Series Compensation (ASC). Example: Single-line diagram ASC Kayenta

Damping circuitCircuitbreaker

Circuitbreaker

Conventionalseriescapacitor 40 Ω

Conventionalseriescapacitor 55 Ω

Damping circuit

Thyristor valve

Reactors

MOVarrester

MOVarrester

MOVarrester

ASC 15 to 60 Ω

Fig. 66: Duties of SVCsFig. 65: Typical single-line diagram of staticVAr compensator (SVC)

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1/39Siemens Power Engineering Guide · Transmission & Distribution

Power Compensation in Transmission Systems

Comparison of reactive powercompensation facilities

Below are the characteristics andapplication areas of series and parallelcompensation and the influence on vari-ous parameter such as short-circuitrating, transmission phase angle andvoltage behavior at the load.

1

2

3

4

5

6 Long transmission lines;Power flow distributionbetween parallel linesand SSR damping

Voltage stabilizationat high load

Reactive powercompensation at lowload; limitation oftemporary overvoltage

Reactive power andvoltage control;damping of powerswings to improvesystem stability

Long transmission lineswith high transmissionpower rating

Short lines, limitationof S. C. power

High

(Very) low

Low

Littleinfluence

Littleinfluence

Littleinfluence

Muchsmaller

(Much)larger

Muchsmaller

Very good

(Very) slight

Very good

Controlled

Voltagedrop

Voltagerise

Littleinfluence

Littleinfluence

Littleinfluence

Increased

Reduced

VariableAdvancedseries com-pensation(ASC)scheme

Seriesreactor

Seriescapacitor

StaticVAr com-pensator(SVC)

Shuntreactor

Shuntcapacitor

Compen-sationelement

Location Short-circuitlevel

Voltageinfluence

Transmis-sion phaseangle

Voltageafter loadrejection

Good for

Behavior of compensation element

E U

E U

SVCE U

E U

E U

(Very) high

(Very) low

Limited bycontrol

ASC

E U

Fig. 68: Components for reactive power compensation

Further information please contact:

Fax: ++ 49-9131-73 45 54

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1/40 Siemens Power Engineering Guide · Transmission & Distribution

Power Compensation in Distribution Systems

Introduction

SIPCON (Siemens Power Conditioner) isa system for the improvement of powerquality in low- and medium-voltage distri-bution networks. This system fits withinthe general framework of EQM equipment(Energy Quality Management). The tre-mendous progress of recent years, withregards to the rating and price of powersemiconductor technology, is reflected inthis system. Using the same hardware,there are various SIPCON configurations.Each configuration is coupled to the electri-cal network in a different manner and hasone or more specific tasks to fulfill.

Areas of application

The manner in which SIPCON is coupledto the network is dependent on the tasksthe system will perform. To distinguishbetween the various configurations, theinitial of the coupling method is attachedto the name SIPCON, leading to thenames SIPCON-P (parallel), SIPCON-S(series) and SIPCON-U (unified). In general,the SIPCON-P is intended for conditioningof the current flowing from a load into thenetwork. It improves the network current.The SIPCON-S improves the quality of thevoltage supplied by the network to theload. It improves the supply voltage quality.The SIPCON-U is a combination of theother two variants and unites theircapabilities.

SIPCON-P improvesnetwork currents

The coupling of the SIPCON-P is three-phase, in parallel to the network and theload (Fig. 69).To fullfill its control task,improvement of the network current, theSIPCON-P injects currents into the PCC(point of common coupling).

Possible applications

1. Active filtering

The current flowing from the load intothe network is measured and dividedinto fundamental and harmonic compo-nents. The SIPCON-P injects currents suchthat load harmonic currents are exclusivelyexchanged between the SIPCON-P andthe load, Harmonic currents thus do notflow on the network side.

2. Dynamic reactive power compensation

The SIPCON-P can dynamically supplystepless reactive power, in both capacitiveand inductive modes. It is possible to gofrom no-load operation to nominal opera-tion in about two network periods. Powerfactor control (cos ϕ-control) is also possi-ble in this mode.

3. Active load balancing

SIPCON-P can inject both positive- andnegative-sequence currents into the PCC.It is thus possible to eliminate negative-sequence currents associated with unbal-anced load conditions, thereby performingactive load balancing.

4. Flicker compensation

Variation in the brightness of lighting sys-tems that is uncomfortable to humans iscalled flicker. Flicker is caused by sudden,stochastic load current peaks which causevoltage drops at the PCC across the net-work impedance.A special flicker algorithm has been de-veloped for SIPCON-P, whereby the peakload currents are exchanged between theSIPCON-P and the load, rather than sup-plied by the network.

5. Active power exchange

An energy source can be connected tothe DC link capacitor, thus allowing energytransfer into the network from the convert-er. The SIPCON-P injects energy in a verynetwork-friendly manner, causing practi-cally no harmonics below 3 kHz.

SIPCON-S improvesthe supply voltage

The series-connected SIPCON-S is coupleddirectly into the power flow via a trans-former (Fig. 70).The SIPCON-S can be viewed as a control-led voltage source connected in serieswith the network.

PCC

IGBT converter

DC link capacitor

SIPCON-PGrid Load

Couplinginductivity

Diodebridge

Trans-former

IGBTconverter

DC link capacitor

SIPCON-SGrid Load

Fig. 71: SIPCON-UFig. 69: SIPCON-P connection

Fig. 70: SIPCON-S connection

Possible applications

1. Voltage sags and swellsIt is possible for the SIPCON-S to add anadditional voltage component to the net-work voltage, thereby compensating volt-age sags and swells.

2. Harmonic reductionBesides the fundamental voltage it isalso possible to generate harmonic volt-ages. If the supply voltage contains har-monic distortion, the SIPCON-S can addup to three discrete voltage harmonicsto the network voltage. The load thussees a less distorted supply voltage.

SIPCON-U improves the networkcurrents and the supply voltage

The SIPCON-U is a combination of theSIPCON-P and SIPCON-S systems.The DC link capacitors of both systemsare connected in parallel, forming a singleDC link capacitor used by both systems(Fig. 71).The SIPCON-U is in fact a UPFC (UnifiedPower Flow Controller) for distribution net-works. The possible applications of such asystem are given by the union of the fea-tures of each single system. In addition,the SIPCON-U can transfer active power inboth directions, so that one SIPCON-U canbe used to compensate both voltage sagsand swells.

Couplinginductivity

Trans-former

IGBTconverter

DC link capacitor

SIPCON-UGrid Load

IGBTconverter

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Power Compensation in Distribution Systems

Power Factor Correction andHarmonic suppression

Basic principles

The vast majority of electrical loads drawnot only active power but also reactivepower which, in the case of motors andtransformers, for example, is required formagnetization and, in the case of staticconverters, as control and communicationreactive power.Generators, overhead transmission lines,cables, transformers and switchgear arerequired for generation and distribution ofelectric power. In addition to active power,reactive power must also be generatedand distributed. This is uneconomical, andthe less reactive power a plant consumes,i.e. the higher its power factor cosϕ is, thelower are the power costs for the plant.The load on the electrical distribution sys-tem can be reduced by installing power-factor correction capacitors close to theloads in the low-voltage system since thereactive power is then supplied by thecapacitors.The transmission losses are less, the pow-er costs are lower and expensive upratingof the distribution system can be avoidedsince more active power can now be trans-mitted by the existing equipment.Capacitors may be employed for individualcompensation, for group compensationor for centralized compensation.It has become standard practice for manyutilities to specify a power factor greaterthan or equal to 0.9.

Harmonics

As a result of continuing development ofpower electronic equipment, the numberof converter-fed loads has increased con-siderably in recent years. Advanced tech-nology employing thyristors is now com-mon to a broad range of applications. Forexample, drives with variable speed andoutput can be operated more economicallyby using converter-fed motors.

20 kV

Incoming feeder frompower system

400 V

M

Iw Ib

Fig. 72: Principle of power factor correction employ-ing low voltage power capacitors

The converter current is composed of aseries of sinusoidal currents, with a funda-mental power frequency component anda series of harmonics, whose frequency isan integer multiple of the power frequen-cy. The harmonic currents are injected inthe three-phase power supply system. Asa result, harmonic voltages, which appearacross the power system impedances,are superimposed on the fundamental fre-quency and thus distort the system volt-age. This can lead to disturbances in thesystem and may cause failure of otherloads.

Design and operation of filter circuits

The effect of harmonic currents on thepower supply system can be reduced toa significant extent by connecting filtercircuits which comprise series resonantcircuits employing reactors in series withcapacitors. The resonant circuits are tunedso as to present an impedance for the indi-vidual harmonic currents, which is almostzero and thus negligible in comparison tothe impedance of the power system. Theharmonic currents of the converters arethus largely absorbed by the filter circuits.Only the remainder flows into the powersupply system. So the voltage is distortedto a lesser degree and interference withother loads is largely obviated.

Power-factor correction by means ofinductive-type capacitors

The use of inductive-type capacitors forpower-factor correction is often necessaryin order to avoid resonance effects. Theirdesign is similar to that of filter circuits,but their resonant frequency lies belowthe 5th harmonic.

As a result, the capacitor unit presents aninductive reactance to all the harmonicscontained in the converter current so thatresonant frequencies cannot occur. Induc-tive-type capacitors and power-factor cor-rection units should be selected and em-ployed in the same manner asnormal capacitors and control units.It is recommended that inductive-typecapacitors be used for cases where morethan 20% of the load is made up of equip-ment which generates harmonics (Fig. 74).

For further information please contact:

Fax: ++ 49- 9131-7313 74

Fig. 73: Resolving of converter current into fundamen-tal-frequency and harmonic components

0 π 2π

UPh

IL

I(1)I(7)I(5)

ϕt

M

to powersystem

Primary distribution system

fromconverterΣI(υ)

Transformer

Low-voltage

Converter

to filtercircuits

υ=5 υ=11,13

υ=7

Filter circuits orinductive-typecapacitors

Fig. 74: Removing the harmonic currents by meansof filter circuits or inductive-type capacitors

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1/42 Siemens Power Engineering Guide · Transmission & Distribution

Surge Arresters

The main task of an arrester is to protectequipment from the effects of overvolt-ages. During normal operation, it shouldhave no negative effect on the powersystem. Moreover, the arrester must beable to withstand typical surges withoutincurring any damage. Nonlinear resistorswith the following properties fulfill theserequirements: Low resistance during surges so that

overvoltages are limited High resistance during normal operation,

so as to avoid negative effects on thepower system and

Sufficient energy absorption capabilityfor stable operation

With this kind of nonlinear resistor, thereis only a small flow of current when contin-uous operating voltage is being applied.When there are surges, however, excessenergy can be quickly removed from thepower system by a high discharge current.Nonlinear resistors, whether comprisingsilicon (SiC) carbide or the metal oxide(ZnO), have proved especially suitable forthis. These two kinds of resistors havedifferent degrees of nonlinearity. Fig. 75shows the current/voltage characteristicsof both types. When SiC resistors areused, series gaps have to be connected inseries to the resistors, whereby the seriesgaps separate the resistors from the pow-er system under power-frequency voltageconditions. Otherwise, an excessively largeamount of current would flow with thiskind of resistor during normal operation.In order to stabilize the sparkover voltageof the series gaps, RC control devices areused (Fig. 76).The nonlinearity of ZnO is considerablymore pronounced than of SiC. For this rea-son, MO arresters, as the arresters withZnO resistors are known today, normallydo not need series gaps.Siemens has many years of experiencewith arresters – whether SiC or MO-based– in low-voltage systems, distribution sys-tems and transmission systems. They areusually used for protecting transformers,generators, motors, capacitors, tractionvehicles, cables and substations.There are special applications such as theprotection of Equipment in areas subject to

earthquakes or heavy pollution Surge-sensitive motors and dry-type

transformers Generators in power stations with

arresters which posses a high degreeof short-circuit current strength

Gas-insulated high-voltage metal-enclosed switchgear (GIS)

Arrester voltage referredto continuous operatingvoltage Û/ÛC

Current through arrester Ia [A]

150 °C

20 °C

115 °C

2

1

010-4

SiC

ZnO

Rated voltage ÛR

Continuous operatingvoltage ÛC

10-3 10-2 10-1 102 103 1041 10

SiC arrester MO arrester

Series spark gapand RC control

SiC dischargeresistor

MO dischargeresistor

Thyristors in HVDC transmissioninstallations

Static compensators Airport lighting systems Electric smelting furnaces in the glass

and metals industries High-voltage cable sheaths Test laboratory apparatus.

Fig. 76: Equivalent circuit diagrams of the two kinds of arresters

Fig. 75: Current/voltage characteristics of non-linear SiC and ZnO resistors

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1/43Siemens Power Engineering Guide · Transmission & Distribution

Surge Arresters

The availability of both technologies,SiC and MO, ensures that arresters canbe inexpensively provided for any kind ofovervoltage problem whatsoever. Due tothe different ways in which they work andtheir different operating characteristics,each kind of arrester technology has itsown very specific advantages.Because of the simpler base materials andmanufacturing procedures of SiC resistors,SiC arresters are less expensive than MOarresters, especially for distribution sys-tems. In addition, the special current/volt-age characteristic of SiC is more favoura-ble for certain applications. It makes senseto use SiC arrester where the qualities ofthe MO arrester cannot be fully exploited.MO arresters are best used in high andextra-high-voltage power systems withsolid neutral earthing. Here, the very lowprotection level and the high energy ab-

sorption capability provided during switch-ing surges are especially important. Forhigh voltage levels, the simple constructionof MO arresters is always an advantage.In contrast, SiC arresters for higher voltag-es are becoming increasingly complicatedin structure and therefore less economical.Another very important advantage of MOarresters is their high degree of reliabilitywhen used in areas with a problematicclimate, for example in coastal and desertareas, or regions affected by heavy indus-trial air pollution. Furthermore, some spe-cial applications have become possibleonly with the introduction of MO arresters.One instance is the protection of capacitorbanks in series reactive-power compen-sation equipment which requires extremlyhigh energy absorption capabilities.Fig. 77 shows two Siemens MO arresterswith different types of housing. In additionto what has been usual up to now – theporcelain housing – Siemens offers alsothe latest generation of high-voltage surgearresters with polymeric housing.Fig. 78 shows the sectional view of suchan arrester. The housing consists of a fiber-glass-reinforced plastic tube with insulatingsheds made of silicone rubber. The advan-tages of this design are absolutely safeand reliable pressure relief characteristics,high mechanical strength even after pres-sure relief and excellent pollution-resistant

Flange with gas diverter nozzle

Seal

Pressure relief diaphragm

Compressing spring

Metal oxide resistors

Composite polymeric housingFRP tube/silicone sheds

properties. The very good mechanical fea-tures mean that Siemens arresters withpolymeric housing (type 3EQ/R) can serveas post insulators as well. The pollution-resistant properties are the result of thewater-repellent effect (hydrophobicity) ofthe silicone rubber, which even transfersits effects to pollution.The polymeric-housed high-voltage arrest-er design chosen by Siemens and the high-quality materials used by Siemens providea whole series of advantages includinglong life and suitability for outdoor use,high mechanical stability and ease of dis-posal.Please find an overview about thecomplete range of Siemens arresters inFig. 79a and 79b.

For further information please contact:

Fax: ++ 49-3 0386 -26721

Fig. 78: Cross section of a polymeric-housed arrester

Fig. 77: Measurement of residual voltage onporcelain-housed (foreground) and polymeric-housed(background) arresters

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1/44 Siemens Power Engineering Guide · Transmission & Distribution

Surge Arresters

3EG4

Metal Oxide MO (gapless type)Silicon Carbide (SiC)(gapped type)

Type

3EA2 3EF13EF23EF3

3EC2 3EE2 3EH2 3EG5 3EG6 3EK5

Application

Maximumsystemvoltage [kV]

Maximumratedvoltage [kVr]

Nominaldischargecurrent [kA]

Maximumenergy ab-sorptioncapability(thermal sta-bility con-dition) [kJ/kVr]

Maximum longduration dis-charge current,2 ms [A]

Maximumpressure reliefcurrent [kA]

Housingmaterial

Porce-lain

Porce-lain

Poly-meric

Metal

3EE13EA1

Over-headlinesys-tems

Over-headlinesys-tems

Distri-butionsys-tems,switch-gear

Distri-butionsys-tems,switch-gear

Distri-butionsys-tems,switch-gear

Distri-butionsys-tems,switch-gear

Distri-butionsystems,metal-enclosedgas-insulatedswitch-gear (GIS)with plug-in connec-tion

Distri-butionsystems,genera-tors,motors,electricfurnaces,6 arresterconnec-tions,powerplants

Distri-butionsystems,genera-tors,motors,electricfurnaces,6 arresterconnec-tions,powerplants

Surgelimiters,motors,dry-typetrans-formers,airfieldlightingsystems

DCsystems,tractionsystems,vehicles

1 24 36 1 12 4 36 52 36 24 36

1 24 42 1 12 4 45 52 45 30 45

5 5 1 5 1 10 10 5 5/10 5/10 10

– 0.3 2.1 0.80.84

– 15 2.2 2.2 2.2 5–

150 150 700 150 2002001300

800 200 2502001700 500

5 ADiscon-nector

20 300 5 ADis-con-nector

40 20 300 16 20 16 20

Poly-meric

Porce-lain

Porce-lain

Porce-lain

Porce-lain

Poly-meric

Poly-mericPorce-lainPoly-meric

3EK6

Distri-butionsys-tems,switch-gear

36

45

10

4.5

300

20

Poly-meric

(1ms)

Fig. 79a: Low- and medium-voltage arresters

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1/45Siemens Power Engineering Guide · Transmission & Distribution

Surge Arresters

3EP1

Metal Oxide MO (gapless type)SiliconCarbide (SiC)(gapped type)

Type

3EP2 3EP3 3EQ1 3EQ2 3EQ33ER3

3EP2-K 3EP2-K3 3EP3-K

Application Transmissionsystems,substations

Trans-missionsys-tems,sub-stations

Trans-missionsys-tems,sub-stations

Trans-missionsys-tems,sub-stations,HVDC,SVC

Trans-missionsys-tems,sub-stations

Trans-missionsys-tems,sub-stations

Trans-missionsys-tems,sub-stations,HVDC,SVC

Trans-missionsystems,sub-stations,metal-enclosedgas-insulatedswitch-gear(GIS)

Trans-missionsystems,sub-stations,metal-enclosedgas-insulatedswitch-gear (GIS,three-phase)

Maximumsystemvoltage [kV]

245 170 420 765 245 525 525 170 170 525

Maximumratedvoltage [kVr]

216 180 384 612 225 444 444 168 168 444

Nominaldischargecurrent [kA]

10 10 20 20 10 20 20 20 20 20

Maximumline dischargeclass

2 2 4 5 3 5 5 4 4 5

2.1 5 10 20 8 13 20 10 10 13

Maximum longduration dis-charge current,2 ms [A]

700 500 1200 3900 800 1600 3900 1200 1200 1600

Maximumpressure reliefcurrent [kA]

50/63 40 50/63 100 40 63 80 63 63 63

Maximumpermissiblecantilevermoment [kNm]

12.5* 2.1* 12.5* 34* 4.6**(> 50 % after pressure relief)

20** 60** – – –

Housingmaterial

Porce-lain

Porce-lain

Porce-lain

Porce-lain

Poly-meric

Poly-meric

Poly-meric

Metal Metal Metal

* Dynamic load acc. to DIN 48113 ** 1.5 · M.M.L. acc. to IEC 36/118/CD

3EM2

Maximumenergy ab-sorptioncapability(thermal sta-bility con-dition) [kJ/kVr]

Trans-missionsystems,sub-stations,metal-enclosedgas-insulatedswitch-gear(GIS)

3EQ1-B

DC sys-tems,tractionsys-tems,vehicles

25

37 (AC) 4 (DC)

10

3

8

800

40

2

Poly-meric

Fig. 79b: High-voltage arresters

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1/46 Siemens Power Engineering Guide · Transmission & Distribution

Worldwide Service forHigh- and Medium-voltage Switchgear and Substations

Siemens provides services for

Circuit-breakers and devices SF6-insulated switchgear Air-insulated switchgear plants Personnel training.

Scope of service:

Maintenance contracts– for switchgear and substations

Regular maintenance– visual inspection– extended visual inspection– overhaul

Emergency troubleshooting– simply call

Phone: ++ 49 - 9131- 74 33 33Mobile: ++ 49 - 171- 337 8653Fax: ++ 49 - 9131- 73 44 49

Fault detection and repair– by experts who will go to the site

on short notice Spare parts delivery

– Reliable, quick and specifically foreach serial number

Documentation– for spare parts and maintenance kits

Assistance in final disposal– classification, storage, organization of

final disposal Personnel training for e.g.

– high voltage, medium voltage,low voltage

– protection and control, generator,transformer, cable accessories

– interlocking device, station controlsystems.

Fig. 80: Extended visual check on site

Fig. 82: Example for a maintenance plan (high voltage,number of years in operation with normal switchingfrequencies)

Visual inspection:to be carried out by suitably trainedcustomer personnel or Siemensmaintenance staffExtended visual inspection:to be carried out by suitably trainedcustomer personnel or Siemensmaintenance staffOverhaul:to be carried out by Siemensmaintenance staff together withcustomer personnel

Number of years

1

2

3

4

5

6

7

8

9

10

11

12

14

15

16

17

18

1920

21

22

23

24

25

26

2728

29

30

31

3233

34

35

36

37

38

39

40

4142

43

44

13

For further information please contact:

Fax: ++ 49-9131-73 4449

Fig. 81: View of the internal components of control unit of an outdoor type high-voltage circuit-breaker

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Medium-Voltage Switchgear

Introduction

Primary and secondary distribution standsfor the two basic functions of the medium-voltage level in the distribution system(Fig. 1).

‘Primary distribution’ means the switch-gear installation in the HV/MV transformermain substations. The capacity of equip-ment must be sufficient to transport theelectrical energy from the HV/MV trans-formers input (up to 63 MVA) via busbarto the outgoing distribution lines or cablefeeders. The switchgear in these mainsubstations is of high importance for thesafe and flexible operation of the distribu-tion system. It has to be very reliable dur-ing its lifetime, flexible in configuration,easy to operate with a minimum of mainte-nance.The type of switchgear insulation (air orSF6) is determined by local conditions, e.g.space available, economic considerations,building costs, environmental conditionsand the relative importance of mainte-nance.Design and configuration of the busbarare determined by the requirements of thelocal distribution system.These are: The number of feeders is given by the

outgoing lines of the system The busbar configuration depends on

the system (ring, feeder lines, oppositestation, etc.)

Mode of operation under normal condi-tions and in case of faults

Reliability requirements of consumer,etc.

Double busbars with longitudinal sectional-izing give the best flexibility in operation.However, for most of the operating situa-tions, single busbars are sufficient if thedistribution system has adequate redun-dancy (e.g. ring-type system).If there are only a few feeder lines whichcall for higher security, a mixed configura-tion is advisable.It is important to prepare enough sparefeeders or at least space in order to extendthe switchgear in case of further develop-ment and the need of additional feeders.As these substations, especially in denselypopulated areas, have to be located right inthe load center, the switchgear must bespace-saving and easy to install.The installation of this switchgear needsthorough planning in advance, including thesystem configuration and future area de-velopment. Especially where existing in-stallations have to be upgraded, the situa-tion of the distribution system should beanalyzed for simplification (system plan-ning and architectural system design).

‘Secondary distribution’ is the local areasupply of the individual MV/LV substationsor consumer connecting stations.The power capacity of MV/LV substa-tions depends on the requirements of theLV system. To reduce the network losses,the transformer substations should beinstalled directly at the load centers withits typical transformer ratings of 400 kVAto max. 1000 kVA. Due to the great num-ber of stations, they must be space-savingand maintenance-free.For high availability, MV/LV substations aremostly looped in by load-break switches.The line configuration is mostly of theopen-operated ring type or of radial strandswith opposite switching station. In case ofa line fault, the disturbed section will beswitched free and the supply is continuedby the second side of the line. This callsfor reliable switchgear in the substations.Such transformer substations can be pre-fabricated units or single components, in-stalled in any building or rooms existing onsite, consisting of medium-voltage switch-gear, transformers and low-voltage distri-bution.Because of the extremely high numberof units in the network high standardizationof equipment is necessary. The mosteconomical solution for such substationsshould have climate-independent andmaintenancefree equipment, so that opera-tion of equipment does not require anymaintenance during its lifetime.Consumers with high power requirementshave mostly their own distribution systemon their building area. In this case, a con-sumer connection station with metering isnecessary. Depending on the downstreamconsumer system, circuit breakers or load-break switches have to be installed.For such transformer substations nonex-tensible and extensible switchgear, for in-stance RMUs, have been developed usingSF6 gas as insulation and arc-quenchingmedium in the case of load-break systems(RMU), and SF6-gas insulation and vacuumas arc-quenching medium in the case ofextensible modular switchgear, consistingof load break panels with or without fuses,circuit-breaker panels and measuringpanels.

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Medium-Voltage Switchgear

Fig. 1: Medium voltage up to 36 kV – Distribution system with two basic functions: Primary distribution and secondary distribution

Customer station with circuit breakerincoming panel and load break switchoutgoing panels

Diagram 1:

Substation

Diagram 2: Diagram 3:

open ring

closed ring

HV/MV transformers up to 63 MVA

MV up to 36 kV

Primary distribution

Secondary distribution

Subtransmission up to 145 kVMain substation

Extensible switchgear for substationwith circuit-breakers e.g. Type 8DH

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Double busbars withdual-feeder breakers

Single busbar withbus-tie breaker

Balancing of feeders on two systemsduring operation

Access to busbars required during oper-ation.

In double-busbars switchboards with dualfeeder breakers it is possible to connectconsumers of less importance by single-busbar panels. This guarantees the highavailability of a double-busbar switchboardfor important panels as, e.g. incomingfeeders, with the low costs and the lowspace requirement of a single-busbarswitchboard for less important panels.These composite switchboards can beachieved with the types 8BK20, 8BJ50 and8DC11.

Type of insulation

The most common insulating mediumhas been air at atmospheric pressure, plussome solid dielectric materials. Under se-vere climatic conditions this requires pre-cautions to be taken against internal con-tamination, condensation, corrosion, orreduced dielectric strength in high alti-tudes.

General

Codes, standards and specifications

Design, rating manufacture and testing ofour medium-voltage switchboards is gov-erned by international and national stand-ards. Mainly all applicable IEC recommen-dations and narrative VDE/DIN standardsapply to our products, whereby it shouldbe noted that in Europe all national electro-technical standards have been harmonizedwithin the framework of the current IECrecommendations.Our major products in this section complyspecifically with the following code publi-cations: IEC 298 AC metal-enclosed switchgear

and controlgear for rated voltages above1 kV and up to and including 72.5 kV

IEC 694 Common clauses for high-voltage switchgear and controlgearstandards

IEC 56 High-voltage alternating-currentcircuit breakers

IEC 265-1 High-voltage switches IEC 470 High-voltage alternating current

contactors IEC 129 Alternating current disconnec-

tors (isolators) and grounding switches IEC 185 Current transformers IEC 186 Voltage transformers IEC 282 High-voltage fusesIn terms of electrical rating and testing,other national codes and specifications canbe met as well, e.g. ANSI C37, 20C,BS 5227, etc.In case of switchgear manufactured out-side of Germany in Siemens factories orworkshops, certain local standards can alsobe met; for specifics please inquire.

Busbar system

Switchgear installations for normal serviceconditions are preferably equipped withsingle-busbar systems. These switch-boards are clear in their arrangement,simple to operate, require relatively littlespace, and are low in inital cost and oper-ating expenses.Double-busbar switchboards can offeradvantages in the following cases: Operation with asynchronous feeders Feeders with different degrees of impor-

tance to maintain operation during emer-gency conditions

Isolation of consumers with shock load-ing from the normal network

Since 1982, insulating sulfur-hexafluoridegas (SF6-gas) at slight overpressure hasalso been used inside totally encapsulatedswitchboards as insulating medium formedium voltages to totally exclude thesedisturbing effects.All switchgear types in this section, withthe exception of the gas-insulated models8D, use air as their primary insulation me-dium. Ribbed vacuum-potted epoxy-resinpost insulators are used as structural sup-ports for busbars and circuit breakersthroughout.In the gas-insulated metal-clad switchgear8D, all effects of the environment on high-voltage-carrying parts are eliminated.Thus, not only an extremely compact andsafe, but also an exceptionally reliablepiece of switchgear is available. The addi-tional effort for encapsulating and sealingthe high-voltage-carrying parts requiresa higher price – at least in voltage ratingsbelow 24 kV. For a price comparison, seethe curves on the following page (Fig. 3, 4).

Primary DistributionSelection Criteria and Explanations

Fig. 2: Basic basbar configurations for medium voltage switchgear

Double busbars withsingle-feeder breakers

Double-busbars switchboardwith single busbar feeders

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Siemens Power Engineering Guide · Transmission & Distribution 2/5

8BJ508DC118DA108BK20

VoltagekV

Single busbar

160

130120110100

908070

0

Percentage

7.2 12 15 24 36

8BJ508DB10

8BK20

Voltage

(8BK20 = 100)!(8BK20 = 100)!

kV

Double busbar

160

130120110100

908070

0

Percentage

7.2 12 15 24 36

Enclosure, Compartmentalization

IEC Publ. 298 subdivides metal-enclosedswitchgear and controlgear into threetypes: Metal-clad switchgear and controlgear Compartmented switchgear and con-

trolgear Cubicle switchgear and controlgear.Thus “metal-clad” and “cubicle” are sub-divisions of metal-enclosed switchgear,further describing construction details.In metal-clad switchgear the componentsare arranged in 3 seperate compartmentsas: Busbar compartment Circuit-breaker compartment Feeder-circuit compartmentwith earthed metal partitions betweeneach compartment.Whereas the cubicle switchgear (type8BJ50) has no compartments within thepanel. The protection against contact withlive busbar is granted by a removeable pro-tective barrier. The protective barrier canbe inserted into the panel without openingthe front door and fulfills the conditions forpartitions according IEC 298.IEC 298-1990-12 Annex AA specifies a“Method for testing the metal-enclosedswitchgear and controlgear under condi-tions of arcing due to an internal fault“.Basically, the purpose of this test is toshow that persons standing in front of, oradjacent to a switchboard during internalarcing are not endangered by the effectsof such arcs. All switchboards describedin this section have successfully passedthese type tests.

Isolating method

To perform maintenance operations safely,one of two basic precautions must betaken before grounding and short-circuitingthe feeder: 1. Opening of an isolator switch with

clear indication of the OPEN condition. 2. Withdrawal of the interrupter carrier

from the operating into the isolationposition.

In both cases, the isolation gap must belarger than the sparkover distance fromlive parts to ground to avoid sparkoverof incoming overvoltages across the gap.The first method is commonly found infixed mounted interrupter switchgear,whereas the second method is appliedin withdrawable switchgear.Withdrawable switchgear has primarilybeen designed to provide a safe environ-ment for maintenance work on circuit inter-

rupters and instrument transformers.Therefore, if interrupters and instrumenttransformers are available that do not re-quire maintenance during their lifetime, thewithdrawable feature becomes obsolete.With the introduction of maintenancefreevacuum circuit-breaker bottles, and instru-ment transformers which are not subjectto dielectric stressing by high voltage,it is possible and safe to utilize totally en-closed, fixed-mounted and gas-insulatedswitchgear. Models 8DA, 8DB and 8DCdescribed in this section are of this design.Due to their much fewer moving parts andtheir total shielding from the environment,they have proved to be much more reliable.All air-insulated switchgear models in thissection except the 8FG10 are of the with-drawable type.

Switching device

Depending on the switching duty in indi-vidual switchboards and feeders, basicallythe following types of primary switchingdevices are used in the switchgear cubi-cles in this section:(Note: Not all types of switching devices can be used inall types of cubicle.)

1. Vacuum circuit-breakers 2. Vacuum contactors in conjunction

with HRC-fuses 3. Vacuum switches or gas-insulated

three-position switch disconnector inconjunction with HRC-fuses.

To 1: Vacuum circuit breaker

In the continuing strive for safer and morereliable medium-voltage circuit breakers,the vacuum interrupter is clearly the firstchoice of buyers of new circuit breakers ona worldwide basis.It is maintenancefree up to 10,000 oper-ating cycles without any limitation by time

and it is recommended for all general-purpose applications. If high numbers ofswitching operations are anticipated (es-pecially autoreclosing in overhead linesystems and switching of high-voltage mo-tors), their use is indicated. They are avail-able in all ratings – see selection matrix onpage 2/66–2/67 for all power switchgearlisted in this section.Due to their freedom of maintenance thesebreakers can be installed inside totallyenclosed and gas-insulated switchgear.

To 2: Vacuum contactors

Vacuum contactors with rated current upto 450 A are used for frequent switchingoperations in motor, transformer, and ca-pacitor bank feeders. They are type-tested,extremely reliable and compact devicesand they are totally maintenancefree. Sincecontactors cannot interrupt fault currents,they must always be used with current-limiting fuses to protect the equipmentconnected. Vacuum contactors can be in-stalled in the metal-enclosed, metal-cladswitchgear type 8BK20 and 8BK30.

To 3: Vacuum switches or …

Vacuum switches and gas-insulated three-position switch disconnectors in primarydistribution switchboards are used mostlyfor small transformer feeders such as aux-iliary transformers or load center substa-tions. Because of their inability to interruptfault currents they must always be usedwith current-limiting fuses. Vacuum switch-es can be installed in the air-insulatedswitchboard type 8BK20 and 8BJ50. Gas-insulated three-position switch disconnec-tors can be installed in the switchboardtype 8DC11.For details of these switching devices seethe following pages!

Primary DistributionSelection Criteria and Explanations

Fig. 3: Price relation Fig. 4: Price relation

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Siemens Power Engineering Guide · Transmission & Distribution2/6

Primary DistributionSelection Matrix

Fig. 5: Primary Distribution Selection Matrix

Standards Insulation Busbar system Enclosure,compartmentalization

Isolating method

Type-tested indoorswitchgear toDIN VDE 0670, Part 6IEC 298

Disconnector,fixed-mounted

Disconnector,fixed-mounted

Disconnector,fixed-mounted

Disconnector,fixed-mounted

Metal-enclosed,cubicle-type

Metal-enclosed,metal-clad

Metal-enclosed,metal-clad

Metal-enclosed,metal-clad

Metal-enclosed,metal-clad

Metal-enclosed,cubicle-type

Metal-enclosed,metal-clad

Triple-polemetal-enclosed,metal-clad

Single-polemetal-enclosed,metal-clad

Single-polemetal-enclosed,metal-clad

Metal-enclosed,cubicle-type

Single busbar

Air-insulated Generatorcircuit-breaker

Double busbar

Single busbar

Double busbar

Generatorcircuit-breaker

Air-insulated

SF6-insulated

Switchgear toDIN VDE 0101

Draw-out section

Draw-out section

Draw-out section

Draw-out section

Draw-out section

Draw-out section

Draw-out section

Containerized switchgear equipped with air-insulated or SF6-insulated switchgear

Disconnector,fixed-mounted

Triple-polemetal-enclosed,metal-clad

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Primary DistributionSelection Matrix

Technical data

Maximum rated short-timecurrent [kA], 1/3 s

Maximum busbar ratedcurrent [A]

Maximum feeder ratedcurrent [A]

4000 4000 2000 2500*

7.2kV

12/15kV

17.5/24kV

36kV

Switchingdevice

Switchgeartype

8BJ50

8BK20

8BK30

8BK40

8BK41

8BJ50

8BK20

8DC11

8DA10

8DB10

8FG10

4000 4000 2500 2500*

7.2kV

12/15kV

17.5/24kV

36kV

50 50 25 31.5*

7.2kV

12kV

17.5/24kV

36kV

2500 2500 2000 –2500 2500 2500 –40 40 25 –

400 400 – –4000 4000 – –50 50 – –

5000 5000 5000** –5000 5000 5000** –63 63 63** –

12500 12500 12500** –– – – –80 80 80** –

2500 2500 2000 –2500 2500 2500 –40 40 25 –

4000 4000 2000 2500*4000 4000 2500 2500*50 50 25 31.5*

1250 1250 1250 –1250 1250 1250 –25 25 25 –

2500 2500 2500 25003150 3150 3150 250040 40 40

2500 2500 2500 25003150 3150 3150 250040 40 40

12500 12500 12500** –– – – –80 80 80** –

Vacuum circuit-breakerVacuum switch

Vacuum circuit-breakerVacuum switchVacuum contactor

Vacuum contactor

Vacuumcircuit-breaker

Vacuumcircuit-breaker

Vacuumcircuit-breaker

Vacuum circuit-breakerSwitch-disconnector

Vacuumcircuit-breaker

Vacuumcircuit-breaker

Vacuumcircuit-breaker

* 36 kV panel: metal enclosed, compartmented ** up to 17.5 kV

Page

2/12

2/8

2/17

2/20

2/24

2/26

2/32

2/32

2/39

2/8

2/12

2/418FF1 ratings acc. to the installed switchgear type

40

40

Vacuum circuit-breakerVacuum switchVacuum contactor

8DC11Vacuum circuit-breakerSwitch-disconnector 1250 1250 1250 –1250 1250 1250 –25 25 25 – 2/26

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Air-insulated SwitchgearType 8BJ50

Stationary part

The cubicle is built as a self-supportingstructure, bolted or riveted together fromrolled galvanized steel sheets and profiles.Cubicles for rated voltages up to 24 kV areof identical construction.A removable protective barrier is used forshielding the busbars without isolatingthem in order, e.g., to work inside the cubi-cle. The protective barrier can be insertedinto the panel without opening the frontdoor and fulfills the conditions for parti-tions according IEC 298. Therefore, thispartition provides same safety features asa metal-clad design.Any overpressure inside the cubicle result-ing from fault arcing is released by pres-sure relief flaps. To reduce internal arcingtimes and thus consequential damages,pressure switches can be installed that tripthe incoming feeder circuit breaker(s) inless than 100 msec. This is an economicalternative to busbar differential protection.

Breaker carriage

The carriage normally supports a vacuumcircuit breaker with the associated operat-ing mechanism and auxiliary devices.Vacuum switches, with or without HV HRCfuses, are optional. By manually movingthe carriage with the spindle drive it can bebrought into a distinct “Connected” and

“Disconnected/Test” position. To thiseffect, the arc- and pressure-proof frontdoor remains closed.To remove the switching element com-pletely from its cubicle, a central servicetruck is used. Inspection can easily andsafely be carried out with the circuit break-er in the “Disconnected/Test” position.All electrical and mechanical parts areeasily accessible in this position.Mechanical spring-charge and contact-position indicators are visible through theclosed door.Local mechanical ON/OFF pushbuttons areactived through the door as well.For complete remote control, the circuit-breaker carriage can be equipped formotor operation.

Low-voltage compartment

All protective relays as well as monitoringand control devices of a feeder can be ac-commodated in a metal-enclosed LV com-partment on top. Device mounting plates,cabling troughs and the central LV terminalstrip(s) are located behind a separate locka-ble door. Full or partial plexiglass windows,or mimic diagrams are available for thesedoors.

Cubicle-type switchgear 8BJ50,air-insulated

From 7.2 to 24 kV Single- and double-busbar

(back-to-back or face-to-face) Air-insulated Type-tested Metal-enclosed Cubicle-type Withdrawable vacuum breaker Vacuum switch optional For indoor installation

Specific features

General-purpose switchgear Circuit breaker mounted on horizontal

slide behind front door Cable connections from front

Safety of operating and maintenancepersonnel

All switching operations behind closeddoors

Positive and robust mechanicalinterlocks

Arc-fault-tested metal enclosure Complete protection against contact

with live parts Line test with breaker inserted (option) Maintenancefree vacuum breaker

Tolerance to environment

Sealed metal enclosure with optionalgaskets

Complete corrosion protectionand tropicalization of all parts (option)

Vacuum-potted ribbed epoxy-insulatorswith high tracking resistance

General description

8BJ50 switchboards consist of metalenclosed cubicles of air-insulated switch-gear with withdrawable vacuum circuitbreakers. The breaker carriage is fully inter-locked with the interrupter and the station-ary cubicle. It is manually moved in hori-zontal direction from the “Connected”position behind the closed front door andwithout the use of auxiliary equipment.A fully isolated low-voltage compartmentis integrated. All commonly used feedercircuits and auxiliary devices are available.The switchgear cubicles and interruptersare factory-assembled and type-tested asper the applicable standards.

Fig. 6: Panel of cubicle-type switchgear 8BJ50(inter-cubicle partition removed)

Fig. 7: Cross section through cubicle-type switchgear8BJ50

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Fig. 8: Double busbar: back-to-back arrangement (cross section)

Fig. 9: Double busbar: face-to-face arrangement (cross section)

Air-insulated SwitchgearType 8BJ50

Main enclosure

The totally enclosed and sealed cubiclepermits installation in most equipmentrooms. With the degree of protection ofIP4X/IP3XD, the switchgear is safeguardedagainst internal contamination, small ani-mals and rodents, and naturally againstcontact with live parts. This eliminates theusual reasons for arc faults.

Busbars and primary disconnects

Rectangular busbars drawn from purecopper are used exclusively. They aremounted in standard cast-resin bushingssupported in the inter-cubicle partitions.The taps to the upper fixed isolating con-tact are mounted on ribbed, cast-resinpost insulators which are sized to take upthe dynamic forces resulting from shortcircuits. The fixed isolating contacts aresilverplated stubs.The movable parts of the line and load-side primary disconnects have flat, spring-loaded and silver-plated hemisphericalpressure contacts for low contact resist-ance and good ventilation. The parallel con-necting arms are designed to increase con-tact pressure during short circuits.

Instrument transformers

Up to three multicore block-type currenttransformers plus three single-phasepotential transformers can be installedwithin the termination zone.The C.T.s carry the cable-connectingbars and lugs, and the fixed contacts ofthe grounding switch. All common burden and accuracy ratingsof instrument transformers are available.Bus bar metering PTs can be fixed installedwithin the busbar zone or in a meteringcubicle, withdrawable PTs and optionallywith current-limiting fuses.

Cable and bar connections

Cables and bars are connected frombelow; entrance from above requires anauxiliary structure behind the cubicle.Single-phase or three-phase solid-dielectriccables can be connected from the front ofthe cubicle; stress cones are installed con-veniently inside the cubicle.Make-proof grounding switches with man-ual operation can be installed below theC.T.s, engaging contacts behind the cablelugs. Operation of the fully interlockedgrounding switch is possible only with thebreaker carriage in the “Disconnected/Test” position.

Interlocking system

A series of sturdy mechanical interlocksforces the operator into the only safe oper-ating sequence of the switchgear, positive-ly preventing the following: Moving the carriage with the breaker

closed and protective barrier inserted. Switching the breaker in any but the

locked “Connected” or “Disconnected/Test” position.

Engaging the grounding switch with thecarriage in the “Connected” position,and moving the carriage into this posi-tion with the grounding switch engaged.

Degrees of protection

Degree of protection IP 4X:In the “Connected” and the “Discon-nected/Test” position of the carriage, theswitchgear is totally protected againstcontact with live parts by objects largerthan 1 mm in diameter.

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Rated voltage

Width

Height min.

Depth single busbardouble busbar

Approx. weightincl. breaker(single busbar cubicle)

7.2

Weights and dimensions

800

2150

1125

500

17.5/24

800/1000

2150

1430

700

12[kV]

[mm]

[mm]

[mm][mm]

[kg]

225011252250

800

2150

500

2860

Air-insulated SwitchgearType 8BJ50

Installation

The switchboards are shipped in sectionsof up to three cubicles on stable woodenpallets which are suitable for rolling andforklift handling. These sections are boltedor spot-welded to channel iron sectionsembedded in a flat and level concrete floor.The switchboard can be installed againstthe wall or freestanding. Double-busbarinstallations in back-to-back configurationare installed freestanding. Cable feed-inis through corresponding cutouts in thefloor; plans for which are part of theswitchgear supply. Three-phase (armored)cables for voltages above 12 kV requiresufficient clearance below the switchgearto split up the phases (cable floor, etc.).Circuit breakers are shipped mounted ontheir carriages inside the switchgear cubi-cles. For preliminary dimensions andweights, see the table to the right.

Fig. 10

Fig. 11

Technical data

* 40 kA/1 s

7.2

12

17.5/24width 800 mm

17.5/24width 1000 mm

Ratedvoltage

Ratedlightning-impulsetest voltage

[kV] [kV]

60

75

95/125

95/125

20

28

38/50

38/50

16202531.540*

16202531.540*

162025

162025

40506380

100

40506380

100

405063

405063

––

––

––

––

–––––

–––––

–––

––

––

–––

–––

Ratedpower-frequencywithstandvoltage

[kV]

Rated short-circuitbreaking current/short-time current(1 s or 3 s available)

[kA](rms)

Rated feedercurrents

630[A]

1250[A]

2000[A]

2500[A]

Rated busbarcurrents

1250[A]

2500[A]

Rated short-circuit makingcurrent

[kA](peak)

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Air-insulated SwitchgearType 8BJ50

Fig. 12: Available circuit options

8BJ50

SectionalizerPanel

Withdraw-able parts

Fixed parts Meteringpanel

Busbarmodules

Bus riser panel Busbar connec-tion panel

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Metal-clad switchgear 8BK20,air-insulated

From 7.2 to 36/38 kV Single- and double-busbar

(back-to-back or face-to-face) Air-insulated Type-tested Metal-enclosed Metal-clad up to 24 kV Compartmented above 24 kV Withdrawable vacuum breaker Vacuum contactor optional Vacuum switch optional For indoor installation

Specific features

General-purpose switchgear Circuit breaker mounted on horizontal

slide behind front door Cable connections from front or rear

Safety of operating and maintenancepersonnel

All switching operations behind closeddoors

Positive and robust mechanicalinterlocks

Arc-fault-tested metal enclosure Complete protection against contact

with live parts Line test with breaker inserted (option) Maintenancefree vacuum breaker

Tolerance to environment

Metal enclosure with optional gaskets Complete corrosion protection and

tropicalization of all parts. Vacuum-potted ribbed epoxy insulators

with high tracking resistance

General description

8BK20 switchboards consist of metal-cladcubicles (compartmented above 24 kV) ofair-insulated switchgear with withdrawablevacuum circuit breakers. Fused vacuumswitches up to 24 kV/800 A and vacuumcontactors up to 12 kV and 400 A can beused optionally. The breaker carriage is ful-ly interlocked with the interrupter and thestationary cubicle. It is manually moved inhorizontal direction from the ”Connected“position behind the closed front door andwithout the use of auxiliary equipment.A fully isolated low-voltage compartmentis integrated. All commonly used feedercircuits and auxiliary devices are available.

Fig. 13: Metal-clad switchgear type 8BK20 (inter-cubicle partition removed)

The switchgear cubicles and interruptersare factory-assembled and type-tested asper the applicable standards.

Stationary part

The cubicle is built as a self-supportingstructure, bolted together from rolled gal-vanized steel sheets and profiles. Cubiclesfor rated voltages up to 24 kV are of identi-cal construction; the 36/38 kV model islarger and uses fiberglass-reinforced epoxyinternal partitions, making it compartment-ed. Each cubicle is divided into threesealed and isolated compartments by parti-tions, i.e. the busbar, cable connection andcircuit-breaker compartment.In the 24 kV version, the fixed contacts ofthe primary disconnects are located withinbushings, effectively maintaining the com-partmentalization in all operating conditionsof the switchgear.The bushings are covered by automaticsteel safety shutters upon removal of thecircuit-breaker carriage from the ”Con-nected“ position.In the 36 kV version, the compartmentsare formed by internal barriers made offiberglass-reinforced epoxy plates withindividual-phase safety shutters that sealin both directions.Each compartment in every model has itsown pressure-relief device. To reduce inter-nal arcing times and thus consequential

damages, pressure switches can be in-stalled that trip the incoming feeder circuitbreaker(s) in less than 100 msec. This is aneconomical alternative to busbar differen-tial protection.

Breaker carriage

The carriage normally supports a vacuumcircuit breaker with the associated operat-ing mechanism and auxiliary devices.Vacuum contactors up to 12 kV and fusedvacuum switches up to 24 kV are optional. By manually moving the carriage with thea spindle drive it can be brought into a dis-tinct ”Connected“ and ”Disconnected/Test“ position. To this effect, the arc- andpressure-proof front door remains closed.To remove the switching element com-pletely from its compartment, a centralservice truck is used. Inspection can easilyand safely be carried out with the circuitbreaker in the ”Disconnected/Test“ posi-tion. All electrical and mechanical parts areeasily accessible in this position.Mechanical spring-charge and contact-position indicators are visible through theclosed door. Local mechanical ON/OFFpushbuttons are actived through the dooras well.For complete remote control, the circuit-breaker carriage can be equipped for motoroperation.

Air-insulated SwitchgearType 8BK20

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Low-voltage compartment

All protective relays, monitoring and con-trol devices of a feeder can be accommo-dated in a metal-enclosed LV compartmenton top (up to 24 kV) or alongside (36/38 kV)the HV enclosure. Device-mounting plates,cabling troughs, and the central LV terminalstrip(s) are located behind a separate lock-able door. Full or partial plexiglass win-dows, or mimic diagrams are available forthese doors.

Main enclosure

The totally enclosed and sealed cubiclepermits installation in most equipmentrooms. With the optional dust protection,the switchgear is safeguarded againstinternal contamination, small animals androdents, and naturally against contact withlive parts. This eliminates the usual rea-sons for arc faults.Should arcing occur, nevertheless, thearc can be guided towards the end of thelineup, where damages are repaired mosteasily. For the latter reason, parititions be-tween individual cubicles of the same bussections are normally not used.

Fig. 14: Cross-section through 8BK20 cubicle

Busbars and primary disconnects

Rectangular busbars drawn from pure cop-per are used exclusively. They are mount-ed on ribbed, cast-resin post insulatorswhich are sized to take up the dynamicforces resulting from short circuits. Solid-dielectric busbar insulation is available.The movable parts of the line- and load-side primary disconnects have flat, spring-loaded and silver-plated hemipherical pres-sure contacts for low contact resistanceand good ventilation. The parallel connect-ing arms are designed to increase contactpressure during short circuits. The fixedcontacts are silver-plated stubs within thecircuit-beaker bushings (24 kV), or the bus-bar mounts (36 kV).

Instrument transformers

Up to three multicore block-type currenttransformers plus three single-phasepotential transformers can be installed inthe lower compartment; PTs optionally onwithdrawable modules up to 24 kV.The C.T.s carry the cable-connecting barsand lugs, and the fixed contacts of the (op-tional) grounding switch. All common bur-den and accuracy ratings of instrumenttransformers are available. Busbar meter-ing PTs with their current-limiting fuses areinstalled on withdrawable carriages, identi-cally to breaker carriages.

Air-insulated SwitchgearType 8BK20

Cable and bar connections

Cables and bars are connected frombelow; entrance from above requires anauxiliary structure behind the cubicle.Single-phase or three-phase solid-dielectriccables can be connected from the front orthe rear of the cubicle (specify); stresscones are installed conveniently inside thecubicle.Regular and make-proof grounding switch-es with manual operation can be installedbelow the C.T.s, engaging contacts behindthe cable lugs. Operation of the fully inter-locked grounding switch is possible onlywith the breaker carriage in the ”Discon-nected/Test“ position.

Interlocking system

A series of sturdy mechanical interlocksforces the operator into the only safe oper-ating sequence of the switchgear, prevent-ing positively the following: Moving the carriage with the breaker

closed. Switching the breaker in any but the

locked ”Connected“ or ”Disconnected/Test“ position

Engaging the grounding switch with thecarriage in the ”Connected“ position,and moving the carriage into this posi-tion with the grounding switch engaged.

Degrees of protection

Degree of protection IP 4X:In the ”Connected“ and the ”Discon-nected/Test“position of the carriage,the switchgear is totally protected againstcontact with live parts by objects largerthan 1 mm in diameter.Optionally, the cubicles can be protectedagainst harmful internal deposits of dustand against dripping water (IP 51).

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Installation

The switchboards are shipped in sectionsof up to three cubicles on stable woodenpallets which are suitable for rolling andforklift handling. These sections are boltedor spot-welded to channel iron sectionsembedded in a flat and level concrete floor.Front-connected types can be installedagainst the wall or freestanding, rear-con-nected cubicles require service aisles.Double-busbar installations in back-to-backconfiguration are installed freestanding.Cable feed-in is through corresponding cut-outs in the floor; plans for which are partof the switchgear supply. Three-phase(armored) cables for voltages above 12 kVrequire sufficient clearance below theswitchgear to split up the phases (cable-floor, etc.). Circuit breakers are shippedmounted on their carriages inside theswitchgear cubicles. For dimensions andweights, see Fig.17.

Fig. 15: Cross section through switchgear type 8BK20in back-to-back double-busbar arrangement for rated voltages up to 24 kV

Fig. 16: Cross section through switchgear type 8BK20in single-busbar arrangement for front cable connection and 36/38 kV 170 kV/BIL

Air-insulated SwitchgearType 8BK20

Fig. 17

Rated voltage

Panel spacing

Width

Depth front conn.without channelwith channel

Depth rear conn.

Approx. weightincl. breaker

7.2

Weights and dimensions

800

2050

1650

17.5 36/38

1775

800

1775

1000

2250

2025

2150

1000

2150

1500

2220

2245

1600

2220

24[kV]

[mm]

[mm]

[mm][mm]

[mm]

[kg]

800

2050

1650

1775

800

1775

800

2050

1650

1775

800

1775

1000

2250

2025

2150

1000

2150

12 15

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7.2

12

15

17.5

24

36/38

Ratedvoltage

Lightningimpulsetest voltage

[kV]

60

75

95

95

125

170

20

28

36

38

50

70/80

16202531.540*50*

16202531.540*50*

16202531.540*50*

162025

162025

162531.5

40506380

110125

40506380

110125

40506380

110125

405063

405063

406380

Powerfrequencytest voltage

[kV]

Rated short-circuit-breakingcurrent/shorttime current(1 or 3savailable)

[kA](rms)

Rated feeder current* Rated busbar currentRatedshort-circuitmakingcurrent

[kA]

–––

–––

–––

–––

630[A]

1250[A]

––

––

––

––

–––

2000[A]

––

––

––

–––

–––

2500[A]

––––

––––

––––

–––

–––

–––

3150[A]

––––

––––

––––

–––

–––

–––

40001)

[A]

Technical data

1250[A]

2000[A]

2500[A]

–––

–––

–––

3150[A]

–––

–––

–––

4000[A][kV]

* 1 s1) Ventilation unit with or without fan and ventilation slots in the front of the cubicle required.

Air-insulated SwitchgearType 8BK20

Fig. 18

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Air-insulated SwitchgearType 8BK20

Fig. 19: Available circuit options

On right endcubicle or bussectonalizer

with solid-insu-lated busbarsbetween twocubicles

8BK20 switchgear up to 24 kV

8BK20 switchgear 36/38 kV

Withdraw-ableparts

PanelFixed busbar Sectionalizer

Model 1Two panels

SectionalizerPanel

Withdraw-ableparts

Fixed parts Meteringpanel

Busbarmodules

Bus riser panel Busbar connec-tion panel

Model 2Two panels with underpass

Meteringpanel

Busbar connec-tion panel(left endpanel only)

Busbarmodules

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Vacuum contactormotor starters 8BK30,air-insulated

From 3.6–12 kV Single-busbar Type-tested Metal-enclosed Metal-clad Withdrawable vacuum contactors

and HRC current-limiting fuses For direct lineup with 8BK20 switchgear For indoor installation

Specific features

Designed as extension to 8BK20 switch-gear with identical cross section

Contactor mounted on horizontally mov-ing truck – 400 mm panel spacing

Cable connection from front or rear Central or individual control power trans-

former Integrally-mounted electronic multifunc-

tion motor-protection relays available.

Safety of operating and maintenancepersonnel

All switching operations behind closeddoors

Positive and robust mechanical inter-locks

Arc-fault-tested metal enclosure Complete protection against contact

with live parts Absolutely safe fuse replacement Maintenancefree vacuum interrupter

tubes

Tolerance to environment

Metal enclosure with optional gaskets Complete corrosion protection and tropi-

calization of all parts Vacuum-potted ribbed expoy insulators

with high tracking resistance

Fig. 20: Metal-clad switchgear type 8BK30 with vacuum contactor (inter-cubicle partition removed)

Air-insulated SwitchgearType 8BK30

Fig. 21

3.67.212

Ratedvoltage

BIL

[kV] [kV]

406060

102028

100020003000

400400400

PFWV

[kV]

Maximumrating ofmotor

[kW]

Rated busbar currentFeederrating

[A]

1250[A]

2000[A]

3150[A]

2500[A]

4000[A]

Technical data

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General description

8BK30 motor starters consist of metal-enclosed, air-insulated and metal-clad cubi-cles. Vacuum contactors on withdrawabletrucks, with or without control powertransformers, are used in conjunction withcurrent-limiting fuses as starter devices.The truck is fully interlocked with the struc-ture and is manually moved from the”Connected“ to the ”Disconnected/Test“position. A fully isolated low-voltage com-partment is integrated. All commonly usedstarter circuits and auxiliary devices areavailable.The starter cubicles and contactors arefactory-assembled and type-tested as perapplicable standards.

Fig. 22: Available circuits

The stationary part

The cubicle is constructed basically thesame as the matching switchgear cubicles8BK20, with the exception of the contactortruck.

Contactor truck

Vacuum contactor, HRC fuses, and controlpower transformer with fuses (if ordered)are mounted on the withdrawable truck.Auxiliary devices and interlocking compo-nents, plus the primary disconnects com-plete the assembly.

Low-voltage compartment

Space is provided for regular bimetallic orelectronic motor-protection relays, plus theusual auxiliary relays for starter control.The compartment is metal-enclosed andhas its own lockable door. All customerwiring is terminated on a central terminalstrip within this compartment.

Main enclosure

Practically identical to the associated8BK20 switchgear.

Busbars and primary disconnects

Horizontal busbars are identical to the onesin the associated 8BK20 switchgear. Pri-mary disconnects are adapted to the lowfeeder fault currents of these starters.Silver-plated tulip contacts with round con-tact rods are used.

C.T.s and cable connection

Due to the limited let-through current ofthe HRC fuse, block-type C.T.s with lowerthermal rating can be used. Depending onthe protection scheme used, C.T.s withone or two secondary windings areinstalled.All commonly used feeder cables up to300 mm2 can be terminated and connect-ed at the lower C.T. terminals.Grounding switches or surge-voltagelimiters are installed optionally below thecurrent transformers.

Reduced-voltage nonreversing (RVNR)with starter (reactor starting)

Full-voltagenonreversing(FVNR)

Reduced-voltage nonreversing (RVNR)with external reactor autotransformer”Korndorffer Method“

Air-insulated SwitchgearType 8BK30

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Interlocking system

Contactor, truck and low-voltage plugs areintegrated into the interlocking system toguarantee the following safeguards: The truck cannot be moved into the

”Connected“ position before the LV plugis inserted.

The LV plug cannot be disconnectedwith the truck in the ”Connected“ posi-tion.

The truck cannot be moved with thecontactor in the ON position.

The contactor cannot be operated withthe truck in any other but the locked”Connected“ or ”Disconnected/Test“position.

The truck cannot be brought into the”Connected“ position with the ground-ing switch engaged.

The grounding switch cannot be en-gaged with the truck in the ”Connect-ed“ position.

Degrees o protection

Degree of protection IP 4X:In the ”Connected“ and the ”Disconnect-ed/Test“ positions of the truck, the starteris totally protected against contact withlive parts with objects larger than 1 mm indiameter.Optionally, the starters can be protectedagainst harmful internal deposits of dustand against dripping or spray water in the”Operating“ position (IP 51).

Installation

Identical to the procedures outlined for8BK20 switchgear. Only the HRC fuses areshipped outside the enclosure, separatelypacked.

Fig. 23: Cross section through switchgear type 8BK30

Air-insulated SwitchgearType 8BK30

Fig. 24

Rated voltage

Width

Height

Depth

Approx. weightincl. contactor

3.6

Weights and dimensions

2 x 400

2050

1650

700

7.2 12[kV]

[mm]

[mm]

[mm]

[kg]

2 x 400

2050

1650

700

2 x 400

2050

1650

700

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Air-insulated SwitchgearType 8BK40

Metal-clad switchgear 8BK40,air-insulated

From 7.2 to 17.5 kV Single- and double-busbar

(back-to-back or face-to-face) Air-insulated Type-tested Metal-enclosed Metal-clad Withdrawable vacuum breaker For indoor installation

Specific features

General-purpose switchgear for ratedfeeder/busbar current up to 5000 A andshort-circuit breaking current up to63 kA

Circuit breaker mounted on horizontallymoving truck

Cable connections from front

Safety of operating and maintenancepersonnel

All switching operations behind closeddoors

Positive and robust mechanicalinterlocks

Complete protection against contactwith live parts

Line test with breaker inserted (option) Maintenancefree vacuum circuit

breaker

Tolerance to environment

Sealed metal enclosure with optionalgaskets

Complete corrosion protection and tropi-calization of all parts

Vacuum-potted ribbed epoxy-insulatorswith high tracking resistance

Generator vacuum circuit breaker panel

Suitable for use in steam, gas-turbine,hydro and pumped-storage power plants

Suitable for use in horizontal, L-shapedor vertical generator lead routing

Fig. 26: Cross section through type 8BK40 generator panel

Fig. 25: Metal-clad switchgear type 8BK40 with vacuum circuit breaker 3AH(inter-cubicle partition removed)

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Air-insulated SwitchgearType 8BK40

General description

8BK40 switchboards consist of metal-cladcubicles of air-insulated switchgear withwithdrawable vacuum circuit breakers. Thebreaker truck is fully interlocked with theinterrupter and the stationary cubicle.It is manually moved in horizontal directionfrom the ”Connected“ position behind theclosed front door and without the use ofauxiliary equipment. A fully isolated low-voltage compartment is integrated.All commonly used feeder circuits and aux-iliary devices are available.The switchgear cubicles and interruptersare factory-assembled and type-tested asper applicable standards.

Stationary part

The cubicle is built as a self-supportingstructure, bolted together from rolled gal-vanized steel sheets and profiles.Cubicles for rated voltages up to 17.5 kVare of identical construction. Each cubicleis divided into three sealed and isolatedcompartments by partitions, i.e. the bus-bar, cable connection and circuit-breakercompartment.The fixed contacts of the primary discon-nects are located within insulating breakerbushings, effectively maintaining the com-partmentalization in all operating conditionsof the switchgear. The bushings are cov-ered by automatic steel safety shuttersupon removal of the circuit-breakerelement from the ”Connected“ position.Each compartment in every model has itsown pressure-relief device. To reduce inter-nal arcing times and thus consequentialdamages, pressure-switches can be in-stalled that trip the incoming-feeder circuitbreaker(s) in less than 100 msec. This is aneconomic alternative to busbar differentialprotection.

Interrupter truck

The truck normally supports a vacuumcircuit breaker with the associated operat-ing mechanism and auxiliary devices.By manually moving the truck with the aspindle drive it can be brought into a dis-tinct ”Connected“ and ”Disconnected/Test“ position. To this effect, the frontdoor remains closed.Inspection can easily and safely be carriedout with the circuit breaker in the ”Discon-nected/Test“ position. All electrical andmechanical parts are easily accessible inthis position.

Mechanical spring-charge and contact-posi-tion indicators are visible through theclosed door. Local mechanical ON/OFFpushbuttons are actived through the dooras well.For complete remote control, the circuitbreaker carriage can be equipped for motoroperation.

Low-voltage compartment

All protective relays, monitoring and con-trol devices of a feeder can be accommo-dated in a metal-enclosed LV compartmenton top the HV enclosure. Device-mountingplates, cabling troughs, and the centralLV terminal strip(s) are located behinda separate lockable door. Full or partialplexiglass-windows, or mimic diagramsare available for these doors.

Main enclosure

The totally enclosed and sealed cubiclepermits installation in most equipmentrooms. With the optional dust protection,the switchgear is safeguarded againstinternal contamination, small animals androdents, and naturally against contact withlive parts. This eliminates the usual rea-sons for arc faults. Should arcing occur,

nevertheless, the arc can be guidedtowards the end of the lineup, where dam-ages are repaired most easily. For the lat-ter reason, partitions between individualcubicles of the same bus sections are nor-mally not used.

Busbars and primary disconnects

Rectangular busbars drawn from purecopper are used exclusively. They aremounted on ribbed, cast-resin post insula-tors which are sized to take up the dyna-mic forces resulting from short circuits.The movable parts of the line- and load-side primary disconnects have flat, spring-loaded and silver-plated hemisphericalpressure contacts for low contact resist-ance and good ventilation. The parallel con-necting arms are designed to increase con-tact pressure during short circuits. Thefixed contacts are silver-plated stubs withinthe circuit-breaker bushings.

Instrument transformers

Up to three multicore block-type currenttransformers plus three single-phasepotential transformers can be installed inthe lower compartment; PTs optionallyon withdrawable modules.

Fig. 27: Cross-section through panel type 8BK40

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7.2

Technical data

Ratedvoltage

Lightning-impulsetestvoltage

Power-frequencytest

Ratedshort-circuit-breakingcurrent/short timecurrent

kA [rms]

Ratedshort-circuit-makingcurrent

[kA]

Rated feedercurrent

1250[A]

2500[A]

3150[A]

5000[A]

5000[A]

5063

20

28

36

38

60

75

95

95

12

15

17.5

125160

[kV] [kV]

Ratedbusbarcurrent

5063

5063

5063

125160

125160

125160

[kV]

Air-insulated SwitchgearType 8BK40

The C.T.s carry the cable-connecting barsand lugs, and the fixed contacts of the (op-tional) grounding switch. All common bur-den and accuracy ratings of instrumenttransformers are available. Busbar meter-ing PTs with their current-limiting fuses areinstalled on a withdrawable truck, identicalto the breaker truck.

Cable and bar connections

Cables and bars are connected frombelow; entrance from above requires anauxiliary structure behind the cubicle.Single-phase or three-phase solid-dielectriccables can be connected from the front ofthe cubicle; stress cones are installed con-veniently inside the cubicle.Regular and make-proof grounding switch-es with manual operation can be installedbelow the C.T.s, engaging contacts behindthe cable lugs. Operation of the fully inter-locked grounding switch is possible onlywith the breaker carriage in the ”Discon-nected/Test“ position.

Interlocking system

A series of sturdy mechanical interlocksforces the operator into the only safe oper-ating sequence of the switchgear, prevent-ing positively the following: Moving the truck with the breaker

closed. Switching the breaker in any but the

locked ”Connected“ or ”Disconnected/Test“ position.

Engaging the grounding switch withthe truck in the ”Connected“ position,and moving the truck into this positionwith the grounding switch engaged.

Degrees of protection

Degree of protection IP 4X:In the ”Connected“ and the ”Disconnect-ed/Test“ position of the truck, the switch-gear is totally protected against contactwith live parts by objects larger than 2 mmin diameter.Optionally, the cubicles can be protectedagainst harmful internal deposits of dustand against drip water (IP 51).

Installation

The switchboards are shipped in sectionsof one cubicle on stable wooden pallettswhich are suitable for rolling and forklifthandling. These sections are bolted orspot-welded to channel iron sections em-bedded in a flat and level concrete floor.

Front-connected types can be installedagainst the wall or freestanding. Double-busbar installations in back-to-back configu-ration are installed freestanding.Cable feed-in is through corresponding cut-outs in the floor; plans for which are partof the switchgear supply. Three-phase(armored) cables for voltages above 12 kVrequire sufficient clearance below theswitchgear to split up the phases (cablefloor, etc.). Circuit breakers are shippedmounted on their trucks inside the switch-gear cubicles. For preliminary dimensionsand weights, see Fig. 28.

Fig. 29

Fig. 28

7.2

1100

2500

2300

2800

Rated voltage

Width

Height

Depth

Approx. weightincl. breaker

Weight and dimensions

12 17.515[kV]

[mm]

[mm]

[mm]

[kg]

1100

2500

2300

2800

1100

2500

2300

2800

1100

2500

2300

2800

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Air-insulated SwitchgearType 8BK40

Fig. 30: Available circuit options for switchgear/generator panel type 8BK40

8BK40 switchgear up to 17.5 kV

PanelWithdraw-ableparts

Fixed parts Meteringpanel

Busbarmodules

Sectionalizer Bus riser panel

8BK40 generator vacuum c.b. panel

Variants Additional parts Optional parts

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Generator circuit breaker unit8BK41, air-insulated

From 7.2 to 17.5 kV Air-insulated Type-tested Metal-enclosed Metal-clad Withdrawable vacuum breaker For indoor installation

Specific features

One cubicle 8BK40 per generator phase Circuit breaker mounted on horizontally

moving truck Suitable for installation in walk-in switch-

gear containers Antimagnetic sheet steel for frames,

partitions and barriers

Safety of operating and maintenancepersonnel

All switching operations behind closeddoors which are part of the interlocking

Positive and robust mechanical interlocks

Complete protection against contactwith live parts

Line test with breaker inserted (option) Maintenancefree vacuum circuit-

breaker

Tolerance to environment

Sealed metal enclosure with optionalgaskets

Complete corrosion protection and tropi-calization of all parts

Vacuum-potted ribbed epoxy-insulatorswith high tracking resistance

Performance ranges

Rated voltages from 7.2 to 17.5 kV Rated short-circuit breaking currents

up to 80 kA Rated currents up to 12.000 A Generator ratings up to

220 MVA at 10.5 kV285 MVA at 13.8 kV325 MVA at 15.75 kV

Applications

Combined-cycle power plants Hydro and pumped-storage power plants Heating and general industrial power

plants

Installation

The generator c. b. unit 8BK41 is shippeddivided into three single cubicles on stablewooden palletts which are suitable for roll-ing and forklift handling. These cubicles arebolted or spot-welded to channel iron sec-tions embedded in a flat and level concretefloor. Circuit breakers are shipped mountedon their trucks in one packing unit.For preliminary dimensions and weights,see Fig. 32.

Fig. 31: Metal-clad generator c. b. unit type 8BK41 (inter-cubicle partition removed)

Fig. 32

Air-insulated SwitchgearType 8BK41

7.2

3 x 1200

2500

2300

3 x 2800

Rated voltage

Width

Height

Depth

Approx. weightincl. breaker

Weights and dimensions

17.5[kV]

[mm]

[mm]

[mm]

[kg]

3 x 1200

2500

2300

3 x 2800

3 x 1200

2500

2300

3 x 2800

3 x 1200

2500

2300

3 x 2800

12 15

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Fig. 33

Fig. 34: Available circuit options for generator c. b. unit type 8BK41

Air-insulated SwitchgearType 8BK41

Basic equipment Standard equipment Maximum equipment

Vacuum circuit breaker,type 3AH on truck

Isolating contacts

Grounding switch(optionally make-proof)

Voltage transfomer

Protective capacitor

Grounding switch withremanence switchingcapacity

Lightning arrester

Generator-side CT

Transfomer-side CT

9

8

7

6

541

2

3

12

6

2

4

12

6

2

4

5

3

12

6

2

4

5

3

9

7

8

4000[A]

6300[A]

8000[A]

––

––

––

10000[A]

–––

–––

–––

––

12500[A]

7.2

Technical data

Ratedvoltage

Lightningimpulsetestvoltage

Powerfrequencytestvoltage

Rated short-circuit-breakingcurrent/short timecurrent

kA [rms]

Ratedshort-circuit-makingcurrent

[kA]

Ratedcurrent

40506380

40506380

40506380

506380

20

28

36

38

60

75

95

95

12

15

17.5

110150190225

110150190225

110150190225

150190225

[kV] [kV][kV]

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Gas-insulated switchgeartype 8DC11

From 3.6 up to 24 kV Triple-pole primary enclosure SF6-insulated Vacuum circuit breakers, fixed-mounted Hermetically-sealed, welded, stainless-

steel switchgear enclosure Three-position disconnector as busbar

disconnector and feeder earthing switch Make-proof grounding with

vacuum circuit breaker Width 600 mm for all versions

up to 24 kV Plug-in, single-pole, solid-insulated bus-

bars with outer conductive coating Cable termination with external cone

connection system to DIN 47 636and CEN HD50651

Operator safety

Safe-to-touch and hermetically-sealedprimary enclosure

All high-voltage parts, including the cablesealing ends, busbars and voltage trans-formers are surrounded by groundedlayers or metal enclosures

Capacitive voltage indication for check-ing for ”dead“ state

Operating mechanisms and auxiliaryswitches safely accessible outside theprimary enclosure (switchgear enclo-sure)

Type-tested enclosure and interrogationinterlocking provide high degree of inter-nal arcing protection

Arc-fault-tested acc. to IEC 298 No need to interfere with the SF6-insu-

lation

Fig. 35: Gas-insulated swichgear with vacuum circuit breakers

SF6-insulated SwitchgearType 8DC11

General description

Due to the excellent experience with vacu-um circuit breaker, gas-insulated switch-gear, there is a worldwide rapidly increas-ing demand of this kind of switchgear evenin the so-called low-range field.The 8DC11 is the result of the economicalcombination of the SF6-insulation and thevacuum technology. The insulating gas SF6is used for internal insulation only; circuitinterruption takes place in standard vacu-um breaker bottles. The safety for the per-sonnel and the environment is maximized.The 8DC11 is completely maintenance-free. The welded gas-tight enclosure ofthe primary part assures an endurance of30 years without any gasworks.

Operational reliability

Hermetically-sealed primary enclosurefor protection against environmentaleffects (dirt, moisture and insects androdents). Degree of protection IP65

Operating mechanism componentsmaintenancefree in indoor environment(DIN VDE 0670 Part 1000)

Breaker-operating mechanisms accessi-ble outside the enclosure (primary enclo-sure)

Inductive voltage transformer metal-enclosed for plug-in mounting outsidethe main circuit

Toroidal-core current transformerslocated outside the primary enclosure,i.e. free of dielectric stress

Complete switchgear interlocking withmechanical interrogation interlocks

Welded switchgear enclosure, perma-nently sealed

Minimum fire contribution Installation independent of attitude for

feeders without HRC fuses Corrosion protection for all climates

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Fig. 36: Cross section through switchgear type 8DC11

SF6-insulated SwitchgearType 8DC11

Fig. 37: Principle of gas monitoring (with ”Ready for service“ indicator)

1. Modular design and compactdimensions

The 8DC switchboards consist of: The maintenancefree SF6-gas-insulated

switching module is three-phase encap-sulated and contains vacuum circuitbreaker and 3 position selector switch(ON/OFF/READY TO EARTH)

Parts for which single-phase encapsula-tion is essential are safe to touch, easilyaccessible and not located in the switch-ing module, e.g. current and potentialtransformers

The busbars are even single-phaseencapsulated, i.e. they are insulated bysilicone rubber with an outer groundedcoating. The plugable design guaranteesa high degree of flexibility and makesalso the installation of busbar c.t.s. andp.t.s. simple.

2. Factory-assembled well-proven test-ed components

A switchgear based on well-proven compo-nents!The 8DC switchgear design is based onassembling methods and componentswhich have been used for years in our SF6-insulated Ring Main Units (RMU). For ex-ample, the stainless-steel switchgear en-closure is hermetically-sealed by weldingwithout any gaskets. Bushings for the bus-bar, cable and PT connection are welded inthis enclosure, as well as the bursting disc,which is installed for pressure relief in theunlikely event of an internal fault. Siemenshas had experience with this techniquesince 1982 because 50,000 RMUs are run-ning troublefree.Cable plugs with the so-called outer-conesystem have been on the market for manyyears.The gas pressure monitoring system is nei-ther affected by temperature fluctuationsnor by pressure fluctuations and showsclearly whether the switchpanel is ”readyfor service“ or not. The monitor is magnet-ically coupled to an internal gas-pressurereference cell, mechanical penetrationthrough the housing is not required. A de-sign safe and reliable and, of course, well-proven in our RMUs.The vacuum circuit breaker, i.e. the vacu-um interrupters and the drive mechanism,is also used in our standard switchboards.The driving force for the primary contactsof the vacuum interrupters is transferredvia metal bellows into the SF6-gas-filledenclosure. A technology that has been suc-cessfully in operation in more than 100,000vacuum interrupters over 20 years.

1

2

3

4

5

6

7

8

9

10

11

12

13

1

34

5

67

89

10

11 12

13

14

14

2

15

15

Low-voltage compartmentBusbar voltage transformer

Busbar current transformer

Busbar

SF6-filled enclosure

Three-position switch

Three-position switchoperating mechanism

Circuit-breaker operatingmechanismCircuit-breaker(Vacuum interrupter)

Current transformers

Double cable connectionwith T-plugs

PT-disconnector

Voltage transformers

Cable

Pressure relief duct

5

6

74

3

1

2

3

4

5

6

7

Signalling contact

Magnet

”Ready for service“ indicator

Pressure cell

Red indicator: Not ready

Green indicator: Ready

Magnetic coupling

Stainless-steelenclosure filled withSF6 gas at 0.5 bar(gauge) at 20 °C

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3. Current and potential transformersas per user’s application

A step forward in switchgear design with-out any restriction to the existing system!New switchgear developments are some-times overdesigned with the need for high-ly sophisticated secondary monitoring andprotection equipment, because current-and potential-measuring devices are usedwith limited rated outputs.The result:Limited application in distribution systemsdue to interface problems with existingdevices; difficult operation and resetting ofparameters.The Siemens 8DC switchgear has no re-strictions. Current and potential transform-ers with conventional characteristics areavailable for all kinds of protection require-ments. They are always fitted outside theSF6-gas-filled container in areas of single-pole accessibility, the safe-to-touch designof both makes any kind of setting and test-ing under all service conditions easy.Current transformers can be installed inthe cable connection compartment at thebushings and, if required additionally, atthe cables (inside the cable connectioncompartment). Busbar CTs for measuringand protection can be placed around thesilicone-rubber-insulated busbars in anypanel.Potential transformers are of the metal-clad plugable design. Busbar PTs aredesigned for repeated tests with 80% ofthe rated power-frequency withstand volt-age, cable PTs can be isolated from thelive parts by means of a disconnectiondevice which is part of the SF6-gas-filledswitching module. This allows high-voltagetesting of the switchboard with AC and thecable with DC without having to removethe PTs.

4. No gas work at site and simplifiedinstallation

The demand for reliable, economical andmaintenancefree switchgear is increasingmore and more in all power supply sys-tems. Industrial companies and power sup-ply utilities are aware of the high invest-ment and service costs needed to keep areliable network running. Preventive main-tenance must be carried out by trained andcostly personnel.A modern switchgear design should notonly reduce the investment costs, also theservice costs in the long run!The Siemens 8DC switchgear has beendeveloped to fulfill those requirements.The modular concept with the mainte-nancefree units does not call for installa-tion specialists and expensive testing andcommissioning procedures. The switchingmodule with the circuit breaker and thethree-position isolator is sealed for life bygas-tight welding without any gaskets.All other high-voltage components are con-nected by means of plugs, a technologywell-known from cable plugs with long-lasting service and proven experience.All cables will be connected by cable plugswith external cone connection system.In case of XLPE cables, several manufac-turers even offer cable plugs with an outerconductive coating (also standard for thebusbars). Paper-insulated mass-impregnat-ed cables can be connected as well byRaychem heat-shrinkable sealing ends andadapters.The pluggable busbars and PTs do notrequire work on SF6 system at site. In-stallation costs are considerably reduced(all components are pluggable) because,contrary to standard GIS, even the siteHV tests can be omitted. Factory-testedquality is ensured thanks to simplifiedinstallation without any final adjustmentsor difficult assembly work.

5. Minimum space and maintenance-free, cost-saving factors

Panel dimensions reduced, cable-connec-tion compartment enlarged!The panel width of 600 mm and the depthof 1225 mm are just half of the truth. Moreimportant is the maximized size of the 8DCswitchgear cable-connection compartment.The access is from the switchgear frontand the gap from the cable terminal to theswitchgear floor amounts to 740 mm.There is no need for any aisle behind theswitchgear lineup and a cable cellar is su-perfluous. A cable trench saves civil engi-neering costs and is fully sufficient withcompact dimensions, such as width 500mm and depth 600 mm.Consequently, the costs for the plot of landand civil work are reduced. Even more,a substation can be located closer to theconsumer which can also solve cablerouting problems.

Busbar

Features

Single-pole, plug-in version Made of round-bar copper, silicon-

insulated Busbar connection with cross pieces

and end pieces, silicon-insulated Field control with the aid of electro-

conductive layers on the silicon-rubberinsulation (both inside and outside)

External layers earthed with the switch-gear enclosure to permit access

Intensive to dirt and condensation Shock-hazard protected in form of metal

covering Switchgear can be extended or panels

replaced without affecting the SF6 gasenclosures.

SF6-insulated SwitchgearType 8DC11

Fig. 38: Plug-in busbar (front view with removed low-voltage panel)

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Optional equipment indicated by means of broken linescan be installed/omitted in part or whole.

Vacuum circuit breakerpanel and three-positiondisconnector

Disconnector panelwith three-positiondisconnector

Switch-disconnectorpanel with three-positionswitch disconnectorand HV HCR fuses

Busbar section with2 three-positiondisconnectors andvacuum circuit breakerin one panel

Busbar make-proofgrounding switch

Circuit-breaker panel Disconnector panel Switch-disconnectorpanel with fuses

1)

Busbar section Busbar make-proofearthing switch

Basic versions

Fig. 41: Switchpanel versions

1) Current transformer; electrically, this is assigned to the switchpanel,its actual physical location, however, is on the adjacent panel.

SF6-insulated SwitchgearType 8DC11

5 6 7

1

4 2 3 1

23

4567

Primary part SF6-insulated,with vacuum interrupterPart of swtichgear enclosureOperating-mechanism box(open)Fixed contact elementPole supportVacuum interrupterMovable contact elementMetal bellowsOperating mechanism

8 9

89

Fig. 39: Vacuum circuit-breaker (open on operating-mechanism side)

Fig. 40: Vacuum circuit-breaker (sectional view)

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[mm]

[mm]

[mm][mm]

[kg][kg]

600

Weights and dimensions

2250

12252400

7001200

Width

Height

Depth single-busbardouble-busbar

Weight single-busbar(approx.) double-busbar

Fig. 42: Technical data of switchgear type 8DC11

Fig. 43

SF6-insulated SwitchgearType 8DC11

Climate and ambient conditions

The 8DC11 fixed-mounted circuit breakeris fully enclosed and entirely unaffectedby ambient conditions. All medium-voltage switching devices

are enclosed in a stainless-steel housing,which is welded gas-tight and filled withSF6 gas

Live parts outside the switchgear enclo-sure are single-pole enclosed

There are no points at which leakagecurrents of high-voltage potentials areable to flow off to ground

All essential components of the operat-ing mechanism are made of noncorrod-ing materials

Ambient temperature range:–5 to +55°C.

Internal arc test

Tests have been carried out with 8DC11switchgear in order to verify its behaviorunder conditions of internal arcing.The resistance to internal arcing complieswith the requirements of: IEC 298 AA DIN VDE 0670 Part 601, 9.84These guidelines have been applied inaccordance with PEHLA Guideline No. 4.

Protection against electric shockand the ingress of water and solidforeign bodies

The 8DC11 fixed-mounted circuit breakeroffer the following degrees of protection: IP3XD for external enclosure IP65 for high-voltage components of

switchpanels without HV HRC fusesin accordance with:– DIN VDE 0470 Part 1– IEC 298 and 529– DIN VDE 0670 Part 6

Cable connection systems

Features

8DC11 switchgear for thermoplastic-insulated cables with cross setionsup to 630 mm2

Standard cable termination height of740 mm

High connection point, simplifyingassembly and cable-testing work

Phase reversal simple, if necessary,due to symmetrical arrangement ofcable sealing ends

Cover panel of cable termination com-partment earthed

Nonconnected feeders:– Isolate– Ground– Secure against re-energizing(e.g. with padlock)

Types of cable termination

Circuit-breaker and disconnector panelswith cable T-plugs for ASG 36-400 bush-ings, with M16 terminal thread accordingto DIN 47 636 Part 6.Switch disconnector panels with elbowcable plugs for ASG 24-250 bushings, withplug-in connection according to DIN 47 636Parts 3 and 4.

7.2Rated voltage

Rated power-frequencywithstand voltage

Rated lightning impulsewithstand voltage

Rated short-circuitbreaking currentRated short-timecurrent, 3s

Rated short-circuitmaking current

Rated busbar current

Rated feeder current

Rated current of switch-disconnector panelswith fuses

Technical data

20

60

25

63

1250

1250

100

12

28

75

25

63

1250

1250

100

36

95

25

63

1250

1250

100

15

50

125

25

40

1250

1250

100

24

38

95

25

63

1250

1250

100

17.5[kV]

[kV]

[kV]

[kA]

[kA]

[A]

[A]

[A]

max.

max.

max. fuse

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SF6-insulated SwitchgearType 8DC11

Fig. 45: Types of cable termination, outer cone system

Fig. 44: Double busbar: Back-to-back arrangement (cross section)

Single cable Double cable Termination for surge arrester Terminationfor switch discon-nector panel

1

2

3

4

5

6

7

8

9

Low voltage compartment

Operating mechanism

Cable connection

Current transformer

Panel link

Busbar

Gas compartment

Three-position switch

Voltage transformer

5

6

7

8

9

1

2

3

4

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SF6-insulated SwitchgearType 8DA/8DB10

Gas-insulated switchgeartype 8DA/8DB10

Single-busbar: type 8DADouble-busbar: type 8DB

From 7.2 to 40.5 kV Single- and double-busbar Gas-insulated Type-tested Metal-clad (encapsulated) Compartmented Fixed-mounted vacuum breaker

Specific features

Practically maintenancefree compactswitchgear for the most severe serviceconditions

Fixed-mounted maintenancefree vacuumbreakers

Only two moving parts and two dynamicseals in gas enclosure of each pole

Feeder grounding via circuit breaker Only 600 mm bay width and identical

dimensions from 7.2 to 40.5 kV

Safety and reliability

Safe to touch – hermetically-sealedgrounded metal enclosure.

All HV and internal drive parts mainte-nancefree for 20 years

Minor gas service only after 10 years Arc-fault-tested Single-phase encapsulation –

no phase-to-phase arcing All switching operations from dead-front

operating panel Live line test facility on panel front Drive mechanism and c.t. secondaries

freely and safely accessible Fully insulated cable and busbar connec-

tions available Positive mechanical interlocking External parts of instrument transform-

ers free of dielectric stresses.

Tolerance to environment

Hermetically-sealed enclosure protectsall high-voltage parts from the environ-ment

Installation independent of altitude Corrosion protection for all climates.

General description

The switchgear type 8DA10 represents thesuccessful generation of gas-insulated me-dium-voltage switchgear with fixed-mount-ed, maintenancefree vacuum circuit break-ers. The insulating gas SF6 is used forinternal insulation only; circuit interruptiontakes place in standard vacuum breakerbottles.

1. Encapsulation

All high-voltage conductors and interrupterelements are enclosed in two identicalcast-aluminum housings, which are ar-ranged at 90° angles to each other. Thealuminum alloy used is corrosionfree.The upper container carries the copperbusbars with its associated vacuum-pottedepoxy insulators, and the three-way selec-tor switch for the feeder with the threepositions ON/ISOLATED/GROUNDINGSELECTED. The other housing containsthe vacuum breaker interrupter. The twohousings are sealed against each other,and against the cable connecting area byarc-proof and gas-tight epoxy bushingswith O-ring seals. Busbar enclosure andbreaker enclosures form separate gascompartments.The hermetical sealing of all HV compo-nents prevents contamination, moisture,and foreign objects of any kind – the lead-ing cause of arcing faults – from enteringthe switchgear. This reduces the require-ment for maintenance and the probabilityof a fault due to the above to practicallyzero. All moving parts and items requiringinspection and occasional lubrication arereadily accessible.

2. Insulation medium

Sulfur-hexafluoride (SF6) gas is the primeinsulation medium in this swichgear.Vacuum-potted cast-resin insulators andbushings supplement the gas and canwithstand the operating voltage in the ex-tremely unlikely case of a total gas loss ina compartment. The SF6 gas serves addi-tionally as corrosion inhibiter by keepingoxygen away from the inner components.The guaranteed leakage rate of any gascompartment is less than 1% per year.Thus no scheduled replenishment of gas isrequired. Each compartment has itsown gas supervision by contact-pressuregauges.

3. Three-position switch and circuitbreaker

The required isolation of any feeder fromthe busbar, and its often desired groundingis provided by means of a sturdy, mainte-nancefree three-way switch arranged be-tween the busbars and the vacuum break-er bottles. This switch is mechanicallyinterlocked with the circuit breaker. Theoperations ”On/Isolated“ and ”Isolated/Grounding selected“ are carried out bymeans of two different rotary levers. Thegrounding of the feeder is completed byclosing the circuit breaker. To facilitatereplacement of a vacuum tube with thebusbars live, the switch is located entirelywithin the busbar compartment.The vacuum circuit breakers used are ofthe type 3AH described on pages 2/66 ffof this section. Mounted in the gas-insulat-ed switchgear, the operating mechanism isplaced at the switchgear front and the vac-uum interrupters are located inside the gasfilled enclosures. The number of operatingcycles is 30,000. Since any switching thatoccurs arc is contained within the vacuumtube, contamination of the insulating gas isnot possible.

4. Instrument transformers

Toroidal-type current transformers withmultiple secondary wingdings are arrangedoutside the metallic enclosure around thecable terminations. Thus there is no highpotential exposed on these c.t.s and sec-ondary connections are readily accessible.All commonly used burden and accuracyratings are available.Bus metering and measuring are by induc-tive, gas-insulated potential transformerswhich are plugged into fully insulated andgas-tight bushings on top of the switch-gear.

5. Feeder connections

All commonly used solid-dielectric insulat-ed single- and three-phase cables can beconnected conveniently to the breaker en-closures from below. Normally, fully insu-lated plug-in terminations are used. Also,fully insulated and gas-insulated busbarsystems of the DURESCA/GAS LINK typecan be used. The latter two terminationmethods maintain the fully insulated andsafe-to-touch concept of the entire switch-gear, rendering the terminations mainte-nance-free as well.In special cases, air-insulated conventionalcable connection is available.

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8DB10

12345

6

7

8

9

10

13

12

11

SF6-insulated SwitchgearType 8DA/8DB10

Fig. 46: Schematic cross section for switchgear type 8DA10, single-busbar

Fig. 47: Schematic cross section for switchtgear type 8DB10, double-busbar

Low-voltage cubicleSecondary equipmentBusbarCast-aluminumDisconnectorOperating mechanism andinterlocking devicefor three-position switchThree-position switchC. B. pole with upper and lowerbushingsC. B. operating mechanismVacuum interrupterConnectionCurrent transformerRack

8DA10

123456

78

910111213

1

2

3

4

6

7

8

9

10

13

12

11

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6. Low-voltage cabinet

All feeder-related electronic protectiondevices, auxiliary relays, and measuringand indicating devices are installed in met-al-enclosed low-voltage cabinets on top ofeach breaker bay. A central terminal stripof the lineup type is also located there forall LV customer wiring. PCB-type protec-tion relays and individual-type protectiondevices are normally used, depending onthe number of protective functions re-quired.

7. Interlocking system

The circuit breaker is fully interlocked withthe isolator/grounding switch by means ofsolid mechanical linkages. It is impossibleto operate the isolator with the breakerclosed, or to remove the switch from theGROUND SELECTED position with thebreaker closed. Actual grounding is donevia the circuit breaker itself.Busbar grounding is possible with theavailable make-proof grounding switch.If a bus sectionalizer or bus coupler is in-stalled, busbar grounding can be done viathe three-way switch and the correspond-ing circuit breaker of these panels.The actual isolator position is positivelydesplayed by rigid mechanical indicators.

Switchgear type 8DB10, double-busbar

The double-busbar switchgear is devel-oped from the components of the switch-gear type 8DA10. Two three-positionswitches are used for the selection of thebusbars. They have their own gasfilledcomponents. The second busbar system islocated phasewise behind the first busbarsystem.The bay width of the switchgear remainsunchanged, depth and height of each bayare increased (see dimension drawingsFig. 49).For parallel bus couplings, only one bay isrequired.

Fig. 48: Dimensions of switchgear type 8DA10, single-busbar

Fig. 49: Dimensions of switchgear type 8DB10, double-busbar

SF6-insulated SwitchgearType 8DA/8DB10

*) dependent on height of frame

850 *

*

2350(2550*)

2660

1525

600

2250

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Degrees of protection

Degree of protection IP 65:By the nature of the enclosure, all high-voltage-carrying parts are totally protectedagainst contact with live parts, dust andwater jets.Degree of protection IP 3XD:The operating mechanism and the low-voltage cubicle have degree of protectionIP 3XD against contact with live parts withobjects larger than 1 mm in diameter. Pro-tection against dripping water is optionallyavailable. Space heaters inside the operat-ing mechanism and the LV cabinet areavailable for tropical climates.

Installation

The switchgear bays are shipped in prefab-ricated assemblies up to 5 bays wide onsolid wooden pallets, suitable for rolling,skidding and fork-lift handling. Double-bus-bar sections are shipped as single or dou-ble bays. The switchgear is designed forindoor operation; outdoor prefabricated en-closures are available. Each bay is set ontoembedded steel profiles in a flat concretefloor, with suitable cutouts for the cablesor busbars. All conventional cables can beconnected, either with fully insulated plug-in terminations (preferred), or with conven-tional air-insulated stress cones. Fully insu-lated busbars are also connected directly,without any HV-carrying parts exposed.Operating aisles are required in front ofand (in case of double-busbar systems)behind the switchgear lineup.

Fig. 50

SF6-insulated SwitchgearType 8DA/8DB10

Fig. 51

Fig. 52

Ambient temperature and current-carrying capacity:

40 °C

35 °C

–5 °C

30 °C

35 °C

40 °C

45 °C

50 °C

Rated ambient temperature (peak)

Rated 24-h mean temperature

At elevated ambient temperatures,the equipment must be derated as follows(expressed in percent of current at ratedambient conditions).

110%

105%

100%

90%

80%

Minimum temperature

=

=

=

=

=

Weights and dimensions

600

6001150

[mm]

[mm][mm]

[mm][mm]

[kg][kg]

Width

Height

Depth

Weight per bay

single-busbardouble-busbar

single-busbardouble-busbar

single-busbardouble-busbar

22502350/2550

15252660

(8DA)(8DB)

(8DA)(8DB)

(8DA)(8DB)

Rated voltage7.2/12/15 kV

Plug size

to 240

120 to 300

Cable cross sections for plug-in terminations

1

2

3

4

17.5/24 kV 36 kV

Cable cross section[mm2] [mm2] [mm2]

400 to 630

to 185

95 to 300

400 to 630

to 185

240 to 500

up to 1200 up to 1200 up to 1200

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SF6-insulated SwitchgearType 8DA/8DB10

Fig. 53

or

Options for circuit-breaker feeder ofswitchgear type 8DA10, single-busbar

Cable or barconnection,nondisconnectibleor disconnectible

or

or

or

or

Voltagetransformer,nondisconnectibleor disconnectible

Make-proofearthingswitch

Busbar currenttransformer

Busbar accessories

Mounted onbreaker housing

Mounted on currenttransformer housing

Mounted onpanel connections

Panelconnection options

Totally gas orsolid-insulated bar

3 x plug-in cablesizes 1 or 2

3 x plug-in cablesize 3

5 x plug-in cablesizes 1 or 2

2 x plug-in cablesizes 1 to 3 withplug-in voltagetransformer

Totally solid-insulatedbar with plug-involtage transformer

Air-insulated cabletermination

Air-insulated bar

Surgearrester

Currenttransformer

1 x plug-in cablesizes 1 to 3 Mounted on

panel connections

Mounted onpanel connections

or

or

or

or

or

or

or

Mounted onpanel connections

Mounted onpanel connections

Mounted onpanel connections

Sectionalizerwithout additionalspace required

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SF6-insulated SwitchgearType 8DA/8DB10

Fig. 54

Options for circuit-breaker feeder ofswitchgear type 8DB10, double-busbar

or

Mounted onpanel connections

Currenttransformer

Voltagetransformer,nondisconnectible

Voltagetransformer,disconnectible

Cable or barconnection,nondisconnectible

Make-proofearthingswitch

Sectionalizerwithout additionalspace required

Busbar currenttransformer

Cable or barconnection,disconnectible

Totally gas orsolid-insulated bar

3 x plug-in cablesizes 1 or 2

3 x plug-in cablesize 3

5 x plug-in cablesizes 1 or 2

2 x plug-in cablesizes 1 to 3 withplug-in voltagetransformer

Totally solid insulatedbar with plug-involtage transformer

Air-insulated cabletermination

Air-insulated bar

1 x plug-in cablesizes 1 to 3

or

or

or

or

or

or

or

Surgearrester

or

or

orand

BB1 BB2

BB1 BB2

BB1 BB2

BB1 BB2 BB1BB2

BB1 BB2 BB1BB2

orBB1 BB2

or

Mounted onpanel connections

Mounted onpanel connections

Mounted onpanel connections

Mounted onbreaker housing

Mounted on currenttransformer housing

BB1BB2

Busbar accessories

BB1BB2

orand

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SF6-insulated SwitchgearType 8DA/8DB10

Fig. 55

7.2

20

60

40

110

3150

2500

12

28

75

36

95

110

15

50

125

24

38

95

17.5[kV]

[kV]

[kV]

[kA]

[kA]

[A]

[A]

Technical data

Rated voltage

Rated power-frequencywithstand voltage

Rated lightning-impulsewithstand voltage

Rated short-circuitbreaking currentand rated short-timecurrent 3s,

Rated short-circuitmaking current

Rated current busbar

Rated current feeder

max.

max.

max.

max.

36 40.5

40

110

40

3150

2500

3150

2500

110

3150

2500

110

3150

2500

110

2500

2500

80

2500

2500

70 80

170 180

31.5404040

For further information please contact:

++ 49 - 91 31-73 46 39

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Generator circuit breakermodule type 8FG10

From 7.2 to 17.5 kV Air-insulated Metal-enclosed

Applications

Combined-cycle power plants Hydro and pumped-storage power plants Heating and general industrial power

plants

Safety of operating and maintenancepersonnel

All switching operations behind closeddoors which are part of the interlocking

Positive and robust mechanicalinterlocks

Complete protection against contactwith live parts

Line test with breaker inserted (option) Maintenancefree vacuum breaker

Tolerance to environment

Sealed metal enclosure with optionalgaskets

Complete corrosion protection and tropi-calization of all parts

Vacuum-potted ribbed epoxy-insulatorswith high tracking resistance

Specific features

Arrangement of circuit breaker anddisconnector in the horizontal bus runwithout current loops

Suitable for indoor or outdoorinstallation

Technical data

Rated voltages from 7.2 to 17.5 kV Rated short-circuit breaking currents

up to 80 kA Rated currents up to 12.500 A Generator ratings up to

220 MVA at 10.5 kV285 MVA at 13.8 kV325 MVA at 15.75 kV

7.2

3200

3200

6300

10,500

Rated voltage

Width

Height

Depth

Approx. weight incl. breaker

Weights and dimensions

[kV]

[mm]

[mm]

[mm]

[kg]

12

3200

3200

6300

10,500

15

3200

3200

6300

10,500

17.5

3200

3200

6300

10,500

Generator SwitchgearType 8FG10

Fig. 56: Metal-enclosed generator c. b. module type 8FG10 with vacuum circuit breakers 3AH

Fig. 57: Cross section through generator c. b. module type 8FG10

Fig. 58

Generator Transformer

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Generator SwitchgearType 8FG10

Fig. 60: Circuit options: Generator c. b. module type 8FG10

Fig. 59: Ratings for generator c.b. module type 8FG10

Generator side Transformer side

3AH vacuumcircuit breaker

Disconnector

Grounding switch(optionally make-proof)

Voltage transformer

Protective capacitor

Grounding switchwith remanenceswitching capacity

Generator-side CT

Transformer-side CT

Lightning arrester

Disconnector for startingequipment

1

2

3

4

5

6

7

8

9

Maximumcomplement

7 8

9

Frequentcomplement

6

5

2

Standard

3

4

1

10

10

–––

–––

–––

––

12500[A]

10000[A]

––

––

––

8000[A]

4000[A]

6300[A]

Ratedshort-circuit-makingcurrent

[kA]

110150190225

110150190225

110150190225

150190225

Rated short-circuit-breakingcurrent/short timecurrent

kA [rms]

40506380

40506380

40506380

506380

Power-frequencytestvoltage

20

28

36

38

[kV]

7.2

Technical data

Ratedvoltage

Ratedcurrent

12

15

17.5

[kV]

Lightning-impulsetestvoltage

60

75

95

95

[kV]

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Containerized switchgear andcontrolgear in modular design

Projects in developing countries or on fast-track schedules frequently do not allow forthe use of conventionally installed electri-cal equipment due to the lack of facilities,skilled labor, or simply time. Modular con-struction of the plants has been used suc-cessfully in these cases, including the pre-fabrication of electrical substations, andother control and automation equipmentcenters. Recognized advantages of thisconcept are: Fabrication of critical electrical subsys-

tems under controlled conditions atmanufacturer’s location

Pretested and commissioned subsys-tems, installed ready for connection offield cables

Shifting of some detailed engineeringto the manufacturer

Containerized Switchgear

Fig. 61: Packaged Substation Hauted el Hamra in the desert Sahara

This results in lower overall constructionperiods and reduced risks in engineeringand scheduling. Direct cost savings arepossible.A variety of standardized and custom-engineered containers is available fromSiemens to meet these requirements.Basically, they are metal-enclosed weather-proof enclosures in self-supporting design,sized to optimally house the specified elec-trical and auxiliary equipment. The contain-ers are outfitted per customer’s specifica-tions on the manufacturer’s premisesunder his direct supervision and are thenshipped as single units to the jobsite. Con-tainers are installed on flat or raised-pierfoundations before the field cables areconnected and the unit is placed in service.Examples of such prefabricated substa-tions include power distribution centers,offshore platform supply systems, pipelinecompressor supply and control stations,high-power variable-speed drive systemsupply and control equipment, diesel and

gas-turbine generating systems, tele-communications and telecontrol stationsfor remote and hostile locations, etc.For details on our standardized containerssee the following pages.

For further information please contact:

++ 49 - 68 94 - 89 12 94

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Standard containers forswitchgear

Factory-assembled packagedsubstations

Walk-in switchgear containers Switchgear operated from the container

aisle

Application/General features

Versatile product range Wide range of container dimensions Ready for connection Installation in any location,

can be moved without difficulty Substations (containers) can be placed

together in rows Fully air-conditioned and pressurized

if required Special versions available, e.g. with bat-

tery compartment, personnel accomoda-tion, office space, cooking facilities,workshop, store room, standby dieselgenerator, etc.

Brief description

All containers are of the same basic con-struction. The load bearing sections are ofhot-dip galvanized steel with folded edges,and welded.The frame consists of the floor, four corneruprights and several central uprights. Theside walls consist of single panels placedbetween the central uprights.The wall panels and doors can be arrangedas required.The cross beams required for the loadpoints (e.g. where switchgear or batteriesare located) can be welded into the floorframe.Large switchgear is installed preferablythrough a temporary opening on the frontface of the substation; for this purpose oneof the uprights is bolted in position ratherthan welded.

Special features of the individualsubstation ranges

Type 8FF11 range

Wall panels in sandwich construction,with 1-mm-thick smooth outer and innersheets; fitted and clamped from outside;wall panels removable.

Inside

Outside

Wall panel

Joint plate

Fig. 62: Packaged substation type 8FF11 including complete Power Control Center

Fig. 63: Packaged substation type 8FF11 wall element construction

Fig. 64: Packaged substation type 8FF12 wall element construction

Containerized Switchgear

Inside

Outside

Wall panel

Joint plate

Ribbed steel plate

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1 2 3 4 5 6

7

8 9 1011 12 13

Roof rim

Roof structure

Threaded bush fortransport frame

Filter

Central uprightwith cover strip

Crane lifting lug

Corner support

Grounding connection

Foundation reinforcement

Steel outer doorwith panic hardware

Opening bar

Wall panel

Floor structure

1

2

3

4

5

6

7

8

9

10

11

12

13

Fig. 65: Packaged substation, type 8FF11

Containerized Switchgear

Fig. 66 Fig. 67: Design features; packaged substation, type 8FF11

12

3

4

56

7

8

9

1

2

3

4

5

6

7

8

9

Wall panelsinside and outside smooth,1 mm thick, sendzimir galvanized,with primer and top coat; 60 mmthick polyester foam fillling

Switchgear floor3 x U sections, 50 mm

Cross beamsPE 120, distance betweeneach beam depending onswitchpanel arrangement

Base structurehot-dip galvanized and weldedsteel plates, with folded edges,5 mm thick

Aislecompressed impregnatedwooden floor boards,35 mm thick

Cable compartmentfor internal wiring

Continuous foundationsconcrete (supplied by customer)

Roofinside and outside trapezoidalsections 1 mm thick, sendzimirgalvanized, with primer andtop coat; 100 mm thick mineralwool filling

Roof structurehot-dip galvanized and weldedsteel plates with folded edges,4 mm thick

Type 8FF12 range

Wall panels in sandwich construction,with 1-mm-thick smooth inner sheet;exterior consisting of continuous weldedsteel sections (3 mm thick). The wall pan-els are fixed and clamped from the inside.

Type 8FF13 range

Special lightweight containers of smalldimensions.

Type 8FF14 range

Special large-dimension container for majorprojects.

150 kg/m2

500 kg/m2

300 kg/m2

RAL 1019RAL 10150.41 W/m2 °K0.56 W/m2 °K

IP 54DIN 4102approx. 10 yearsapprox. 20 years

RoofFloor structureWall panelsColour ofload bearing partswall panelK-value of roofK-value of wall panels,doorsDegree of protectionFire resistanceCorrosion resistanceOperating life

Permitted load

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Order No.suffixes

Length

Height

Width

substationtype

54321

4321

4321

12

1 2 3 4 5 6 7

8 F F 1

1173410236873872405742

Internaldimensions[mm]

3500325027502500

3420320629962778

6. Digit

8. Digit

7. Digit

5. Digit

From switchgear flooringor aisle surface

1 = With smooth individual outer wall panels2 = With continuous welded steel section outer wall

Order No.suffixes

Length

Height

Width

Substationtype

54321

4321

4321

12

1 2 3 4 5 6 7 88 F F 1

1173410236873872405742

Internaldimensions*[mm]

3500325027502500

3420320629962778

*External dimensions = internal dimensions + xfor length (Floor structure) x = 208 mm

(Roof structure) x = 250 mmfor height x = 520 mmfor width x = 208 mm

Fig. 68: Determining Order Nos. for packaged substation containers

Fig. 69: Example: Plan view of packaged station (Container), type 8FF11

Heater HeaterFilter fan Filter fan Power socketLight switch

Battery

Battery chargerFilter

Distribution box

2778

11734

Emergency lightingFluorescent lamps

SwitchboardAuxiliarytrans-former

Dimensions in mm

Containerized Switchgear

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60°≥

Containerized Switchgear

Transport

The substations can be transported byroad or ship. For loading and unloading,four crane lifting lugs are provided, boltedto the two roof crossbeams. Four diagonaltie bars are attached to each side; theseare removed after unloading.The substations are supplied ready forconnection, with all equipment installed,including the transformer.Special models in the type 8FF14 rangeabove 18 m length are split up for trans-port.

Installation

Packaged substation containers are prefer-ably installed individually, but they can alsobe arranged as shown in the illustration.If containers are combined on-site, theconnecting walls are temporary and areremoved prior to installation. For sea trans-port, the units are sealed and protectedagainst water ingress and damage of thejointing surfaces.The substation can be placed on flat con-crete or steel foundations or on raised stripor pier foundations.

Fig. 72: Substation type 8FF11 with medium-voltageand low-voltage switchgear; split double housing

Fig. 73: Substation type 8FF11 with mimic boardinstalled

Fig. 70: Substation type 8FF11 with split-type airconditioners

Fig. 71: Substation type 8FF11 with control room,fitted sun roof and exterior lighting

Fig. 75: Lifting substation by single craneFig. 74: Arrangement variations substation type 8FF1

L-shaped arrangement

Individual

Side by side

End to end

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Secondary DistributionSwitchgear and Transformer Substations

General

The secondary distribution network withits basic design of ring-main systems withcounter stations as well as radial-feedtransformer substations are designed inorder to reduce network losses and toprovide an economical solution for switch-gear and transformer substations.They are installed with an extremely highnumber of units in the distribution net-work. Therefore, high standardization ofequipment is necessary and economical.The described switchgear will show suchqualities.To reduce the network losses the trans-former substations should be installeddirectly at the load centers.The transformer substations consisting ofmedium-voltage switchgear, transformersand low-voltage distribution can be de-signed as prefabricated units or singlecomponents installed in any building orrooms existing on site.Due to the large number of units in thenetworks the most economical solution forsuch substations should have climate-inde-pendent and maintenancefree equipmentso that operation of the equipment doesnot need any maintenance work during itslifetime.For such transformer substations nonex-tensible and extensible switchgear, for in-stance RMUs, have been developed usingSF6-gas as insulation and arc-quenchingmedium in the case of load-break systems(RMU), and SF6-gas insulation and vacuumas arc-quenching medium in the case ofextensible modular switchgear, consistingof load break panels with or without fuses,circuit-breaker panels and measuringpanels.Siemens developed RMUs in accordancewith these requirements.Ring-main units type 8DJ10, 8DJ20,8DJ30, 8DJ40 and 8DH10 are type-tested,factory-finished, metal-enclosed, SF6-insu-lated indoor switchgear installations. Theyverifiably meet all the demands encoun-tered in network operation by virtue of thefollowing features:

Features

Maximum personnel safety

High-grade steel housing and cable con-nection compartment tested for resist-ance to internal arcing

Logical interlocking Guided operating procedures Capacitive voltage indication integrated

in unit Safe testing for dead state on the

closed-off operating front Locked, grounded covers for fuse as-

sembly and cable connection compart-ments

Safe, reliable, maintenancefree

Corrosion-resistant hermetically weldedhigh-grade steel housing without sealsand resistant to pressure cycles

Insulating gas retaining its insulating andquenching properties throughout theservice life

Single-phase encapsulation outsidethe housing

Clear indication of readiness foroperation, unaffected by temperatureor altitude

Complete protection of the switchdisconnector/fuse combination, evenin the event of thermal overload ofthe HV HRC fuse (thermal protectionfunction)

Reliable, maintenancefree switchingdevices

Excellent resistance to ambient conditions

Robust, corrosion-resistant and mainte-nancefree operating mechanisms

Maintenancefree, all-climate, safe-to-touch cable terminations

Creepage-proof and free from partialdischarges

Maintenancefree, safe-to-touch,all-climate HV HRC fuse assembly

Environmental compatibility

Simple, problemfree disposal of theSF6 gas

Housing material can be recycled bynormal methods

Standards

The fixed-mounted ring-main unitstype 8DJ10, 8DJ20, 8DJ30, 8DJ40 and8DH10 comply with the followingstandards:

In accordance with the harmonizationagreement reached by the IEC memberstates, that their national specificationsconform to IEC Publication No. 298.

For further information please contact:

Fax: ++ 49 - 91 31-73 46 36

IEC 694

IEC 298

IEC 129

IEC 282

IEC 265–1

IEC 420

IEC 56

IEC Standard VDE Standard

VDE 0670 part 1000

VDE 0670 part 6

VDE 0670 part 2

VDE 0670 part 4

VDE 0670 part 301

VDE 0670 part 303

VDE 0670 part 101–107

Fig. 76

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Secondary DistributionSwitchgear and Transformer Substations

Fig. 77: Secondary Distribution Network

G

RMU for transformersubstationsType 8DJ

Secondarydistribution

Primarydistribution

Extensible switchgearfor consumersubstationsType 8DH or 8AA

Extensible switchgearfor substations withcircuit breakersType 8DH or 8AA

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Nonextensible

Codes,standards

Type ofinstallation

Insulation Enclosure Switchingdevice

Metal -enclosedfixed-mounted Load-break switch

Medium-voltageindoor switchgear,type-testedaccording to:IEC 298DIN VDE 0670, Part 6

Extensible

SF6 -gas-insulated

Air-insulated Metal-enclosedLoad-break switchVacuumc. b.Measurement panels

Switchgear

Transformer-substations Execution ofthe transformer substation

Prefabricated, factory-assembled substation

Load-break switchVacuumc. b.Measurement panels

Metal -enclosedfixed-mounted

SF6-gas-insulated

Secondary DistributionSelection Matrix

Fig. 78

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3s1s

2/50

2/53

2/58

2/62

Switchgeartype

RMU for transformersubstations 8DJ10

Single panel, fusedfor one transformer

8DJ20

Ultracompact RMUup to 12 kV

8DJ30

8DJ40RMU for extreme lowsubstation housings

Consumer substationc. b. switchgear 8DH10

8AA20

Technical data Page

InsulationBIL7.2/12[kV]

17.5/24[kV]

Design voltageInsulation

[kV]

Maximum ratedshort-time current

[kA] [kA]

Rated current

Busbar max.[A]

Feeder[A]

60/75 95/125

60/75 95/125

60/75 95/125

7.2–24

7.2–24

7.2–12

7.2–24

25 20

25 20

25 20

20 20

630 up to 630

Consumer substationc. b. switchgear

25 20

20 11.5

20 11.5

16 9.3

7.2–15

17.5–24

7.2–12

17.5–24

1250 up to 630

1000 up to 1000

630 up to 630

Packagesubstation type(Example)

8FB12/64

2/56

2/54

Page

Application

8FB108FB118FB12

8FB158FB168FB17

Type of housing

630 kVA

up to 1000/1250 kVA

Transformerrating

8DJ108DJ208DJ308DJ40

HV-sectionMedium-voltageswitchgear type

630 up to 630

630 up to 630

630 up to 630

60/75 95/125

60/75 95/125

60/75 95/125

Secondary DistributionSelection Matrix

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Secondary DistributionSwitchgear Type 8DJ10

Fig. 79: Nonextensible RMU, type 8DJ10

Ring-main unit type 8DJ10,7.2–24 kVnonextensible, SF6-insulated

Typical use

SF6-insulated, metal-enclosed fixed-mount-ed Ring-main units (RMU) type 8DJ10 areused for outdoor transformer substationsand indoor substation rooms with a varia-bility of 25 different schemes as a standarddelivery program.More than 55,000 RMUs of type 8DJ10are in worldwide operation.

Specific features

Maintenancefree, all-climate SF6 housings have no seals Remote-controlled motor operating

mechanism for all auxiliary voltages from24 V DC to 230 V AC

Easily extensible by virtue of trouble-freereplacement of units with identical cableconnection geometry

Standardized unit variants for operator-compatible concepts

Variable transformer cable connectionfacilities

Excellent economy by virtue of ambientcondition resistant, maintenancefreecomponents

Versatile cable connection facilities,optional connection of mass-impregnat-ed or plastic-insulated cables or plugconnectors

Cables easily tested without having tobe dismantled

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Fig. 81: Cross section of SF6-insulated ring-main unit 8DJ10

Secondary DistributionSwitchgear Type 8DJ10

Fig. 82: “Three-position load-breakswitch”ON–OFF–EARTH

Rated frequency

Rated current ofcable feeders

Rated current oftransformer feeders2)

Rated power-frequencywithstand voltage

Rated lightning-impulsewithstand voltage

Rated short-circuitmaking current of cablefeeder switches

Rated short-circuitmaking current oftransformer switches

Rated short-circuit current, 1s

Ambient temperature

7.2

50/60

400/630

200

20

60

63

25

25

min. – 50max. +80

[Hz]

[A]

[A]

[kV]

[kV]

[kA]

[kA]

[kA]

[°C]

1) Higher values on request2) Depending on HV HRC fuse assembly

12

50/60

400/630

200

28

75

52

25

21

50/60

400/630

200

36

95

52

25

21

50/60

400/630

200

38

95

52

25

21

50/60

400/630

200

50

125

40

25

16

15 17.5 24[kV]

Technical data (rated values)1)

Rated voltage andinsulation level

min. – 50max.+80

min. – 50max. +80

min. – 50max. +80

min. – 50max. +80

Fig. 80

1

2

3

4

5

6

HRC fuse boxes

Hermetically-scaled weldedstainless steel enclosure

SF6 insulation/quenching gas

Three-position load-break switch

Feeder cable with insulatedconnection alternative withT-plug system

Maintenancefree stored energy

1

2

3

4

5

6

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Fig. 83: Schemes and dimensions

Secondary DistributionSwitchgear Type 8DJ10

Dimensions [mm]

800

800

1360

1760

1170

800

1360

1760

1630

800

1360

1760

2070

800

1360

1760

1450

800

1105

1505

1700

800

Scheme 64Scheme 61

Examples out of 25 standard schemes

Without HV HRC fuses Combinations

With integrated HV HRC fuse assembly

Dimensions [mm]

WidthDepthHeight Version with

low support frameVersion withhigh support frame

Scheme 10 Scheme 71 Scheme 81

Scheme 70

1360

1760

WidthDepthHeight Version with

low support frameVersion withhigh support frame

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Single panel forone transformer feeder,type 8DJ20, 7.2–24 kVnonextensible, SF6-insulated

Typical use

SF6-insulated, metal-enclosed, fixed-mounted single panels type 8DJ20 areused for dead-end lines to feed one trans-former, e.g. instead of pole-mountedequipment, installed in substation housingsor any indoor rooms.

Specific features

Minimal dimensions Ease of operation Proven components from the

8DJ10 range Metal-enclosed All-climate Maintenancefree Capacitive voltage taps for

– incoming feeder cable– outgoing transformer feeder

Optional double cable connection Optional surge arrester connection Transformer cable connected via straight

or elbow plug Motor operating mechanism for auxiliary

voltages of 24 V DC–230 V ACFig. 84: Nonextensible single panel for transformer feeder type 8DJ20

Fig. 85

1) Higher values on request2) Depending on HV HRC fuse assembly

[kV]

[Hz]

[A]

[kV]

[kV]

[kA]

[kA]

[°C]

7.2

50/60

200

20

60

25

min. – 40max. +70

10

12

50/60

200

28

75

25

10

15

50/60

200

36

95

25

10

17.5

50/60

200

38

95

25

10

24

50/60

200

50

125

25

10

Rated frequency

Rated current oftransformer feeders2)

Rated power-frequencywithstand voltage

Rated lightning-impulsewithstand voltage

Rated short-circuitmaking current oftransformer switches

Rated short-circuit current, 1s

Ambient temperature

Technical data (rated values)1)

Rated voltage andinsulation level

min. – 40max. +70

min. – 40max. +70

min. – 40max.+70

min. – 40max.+70

575

760

1400

[mm]

[mm]

[mm]

Width

Depth

Height

Dimensions

Transformer spur panel

Fig. 86

Secondary DistributionSwitchgear Type 8DJ20

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Secondary DistributionSwitchgear Type 8DJ30

Fig. 87: Nonextensible RMU, type 8DJ30

Ring-main unittype 8DJ30, 7.2–12 kVultracompact, nonextensibleSF6-insulated

Typical use

SF6-insulated, metal-enclosed, fixed-mounted Ring-main units type 8DJ30 aredesigned as ultracompact transformer sub-stations with extremly small dimensions.

Specific features

Optimized compact design Ease of cable testing by means

of bushings Test bushing covers arranged and

locked panel by panel,minimal effortlogical interlocking

Variable cable connectionwith cable plugs andconventional sealing ends

Optional floor orwall mounting

All-climate Maintenancefree Capacitive voltage taps for

– incoming feeder cable– optional outgoing transformer feeder

Optional motor operating mechanismfor auxiliary voltagesof 24 V DC–230 V AC

Optional plug-in grounding links

Rated frequency

Rated current ofcable feeders

Rated current oftransformer feeders2)

Rated power-frequencywithstand voltage

Rated lightning-impulsewithstand voltage

Rated short-circuitmaking current of cablefeeder switches

Rated short-circuitmaking current oftransformer switches

Rated short-circuit current, 1s

Ambient temperature

[kV]

Technical data (rated values)1)

Rated voltage andinsulation level

7.2 12

50/60

400/630

200

20

60

63

25

25

min. – 40max. +70

50/60

400/630

200

28

75

52

25

21

1) Higher values on request2) Depending on HV HRC fuse assembly

[Hz]

[A]

[kV]

[kA]

[kA]

[kA]

[°C]

[kV]

[A]

min. – 40max. +70

Fig. 88

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Secondary DistributionSwitchgear Type 8DJ30

Fig. 89: Schemes and dimensions

920

540

945

1700

670

540

945

1700

1140

540

945

12001200 1200

1700

Width

Depth

Height

Scheme 10 Scheme 32 Scheme 71

Versionwall-mountedwithout support frame

Version withlow support frame

Version withhigh support frame

Dimensions [mm]

Individual panels

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Secondary DistributionSwitchgear Type 8DJ40

Ring-main unittype 8DJ40, 7.2–24 kVnonextensible, SF6-insulated

Typical use

SF6-insulated, metal-enclosed, fixed-mounted. Ring-main units type 8DJ40 aremainly used for transformer compact sub-stations. The main advantages of thisswitchgear is the extremely high cable ter-mination for easy cable connection and ca-ble testing works.

Specific features

8DJ40 units are type-tested, factory-finished, metal-enclosed SF6-insulatedswitchgear installations and meet thefollowing operational specifications: High level of personnel safety and

reliability High availability High-level cable connection Minimum space requirement Uncomplicated design Separate operating mechanism

actuation for switch disconnectorand make-proof grounding switch,same switching direction in linewith VDEW recommendation

Ease of installation Motor operating mechanism

retrofittable Optional stored-energy release for

ring cable feeders Maintenancefree All-climate

Fig. 90: Nonextensible RMU, type 8DJ40

Fig. 91

Rated frequency

Rated current ofcable feeders

Rated current oftransformer feeders

Rated power-frequencywithstand voltage

Rated lightning-impulsewithstand voltage

Rated short-circuitmaking current ofcable feeder switches

Rated short-circuitmaking current oftransformer switches2)

Rated short-time currentof cable feeder switches

Rated short-circuit time

Rated filling pressureat 20 °C

Ambient temperature

[kV]

Technical data (rated values)1)

Rated voltage andinsulation level

12 24

50

400/630*

≤ 200

28

75

50 (31.5)*

25

1

20 (12.5)*

0.5

min. – 40max. +70

[Hz]

[A]

[A]

[kV]

[kV]

[kA]

[kA]

[kA]

[s]

[barg]

[°C]

50

400/630*

≤ 200

50

125

40 (31.5)*

25

1

16 (12.5)*

0.5

min. – 40max. +70

1) Higher values on request* With snap-action/stored-energy operating mechanism up to 400 A/12.5 kA, 1s2) Depending on HV HRC fuse assembly

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Secondary DistributionSwitchgear Type 8DJ40

Fig. 92: Schemes and dimensions

Width

Depth

Height

Scheme 10 Scheme 32

1140

760

1400/1250

909

760

1400/1250

Scheme 71

1442

760

1400/1250

Dimensions [mm]

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Secondary DistributionSwitchgear Type 8DH10

The units have an grounded outer enclo-sure and are thus shockproof. This alsoapplies to the fuse assembly and thecable terminations. Plug-in cable sealingends are housed in a shock-proof metal-enclosed support frame

Fuses and cable connections are onlyaccessible when earthed

All bushings for electrical and mechani-cal connections are welded gas-tightwithout gaskets

Three-position switches are fitted forlead switching, disconnection andgrounding, with the following switchpositions: closed, open and grounded.Make-proof earthing is effected by thethree-position switch (shown at page2/51)

Each switchgear unit can be composedas required from single panels and(preferably) panel blocks, which maycomprise up to three combined singlepanels

The 8DH10 switchgear is maintenance-free

Integrated current transformer suitablefor digital protection relays and protec-tion systems for c.t. operation release

Fig. 93: Extensible, modular switchgear type 8DH10

Consumer substationmodular switchgear type 8DH10extensible, SF6-insulated

Typical use

SF6-insulated, metal-enclosed fixed-mount-ed switchgear units type 8DH10 are indoorinstallations and are mainly used for powerdistribution in customer substations ormain substations.The units are particularly well suited forinstallation in industrial environments,damp river valleys, exposed dusty or sandyareas and in built-up urban areas.They can also be installed at high altitudeor where the ambient temperature is veryhigh.

Specific features

8DH10 fixed-mounted switchgear units aretype-tested, factory-assembled, SF6-insulat-ed, metal-enclosed switchgear units com-prising circuit-breaker panels, disconnectorpanels and metering panels.They meet the demands made on medi-um-voltage switchgear, such as High degree of operator safety, reliability

and availability No local SF6 work Simple to install and extend Operation not affected by environmental

factors Minimum space requirements Freedom from maintenance is met sub-

stantially better by these units than byearlier designs.

Busbars from panel blocks are locatedwithin the SF6 gas compartment. Con-nections with individual panels and otherblocks are provided by solid-insulatedplug-in busbars

Single-phase cast-resin enclosed insulat-ed fuse mounting outside the switch-gear housing ensures security againstphase-to-phase faults

All live components are protectedagainst humidity, contamination, corro-sive gases and vapours, dust and smallanimals

All normal types of T-plugs for thermo-plastic-insulated cables up to 300 m2

cross-section can be accommodated

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Secondary DistributionSwitchgear Type 8DH10

Fig. 94: Cross section of transformer feeder panel

Fig. 96: Combination of single panels with plug-in type, silicon-insulated busbar.No local SF6 gas work required during assembly or extension

Fig. 97: Cross section of silicon-pluged busbarsection.

LV cabinet

extensibleextensible

1

2

3

4

5

1

2

3

4

5

67

8

10

9

Fuse assemblyThree-position switchTransformer/cable feeder connectionHermetically-welded gas tankPlug-in busbar up to 1250 A

12345

Low-voltage compartmentCircuit-breaker operating mechanismMetal bellow welded to the gas tankPole-end kinematicsSpring-assisted mechanism

12345

Three-position switchRing-main cable termination(400/630 A T-plug system)Hermetically-welded RMU housingBusbar (up to 1250 A)Overpressure release system

67

89

10

Fig. 95: Cross section of circuit-breaker feeder panel

2

43

1

Plug bushing welded to the gas tank

Silicon adapter

Silicon-insulated busbar

Removable insulation cover toassemble the system at site

1

2

3

4

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Secondary DistributionSwitchgear Type 8DH10

Fig. 98

Rated frequency

Rated power-frequencywithstand voltage

Rated lightning-impulsewithstand voltage

Rated short-circuitbreaking current ofcircuit-breakers

Rated short-circuitcurrent, 1s

Rated short-circuitmaking current

Busbar rated current

Feeder rated current– Circuit-breaker panels– Ring-main panels– Transformer panels*

Rated current of bussectionalizer panels– without HV HRC fuses– with HV HRC fuses*

Technical data (rated values)1)

Rated voltage andinsulation level

7.2

[Hz]

[kV]

[kV]

[kA]

[kA]

[kA]

[A]

[max. A][max. A][max. A]

[A][A]

12 15 17.5 24

50/60

20

60

25

25

63

6301250

400/630200

400/630400/630200

50/60

28

75

25

25

63

6301250

400/630200

400/630400/630200

50/60

36

95

20

20

50

6301250

400/630200

400/630400/630200

50/60

38

95

20

20

50

6301250

400/630200

400/630400/630200

50/60

50

125

16

16

50

6301250

400/630200

400/630400/630200

1) Higher values on request* Depending on HV HRC fuse assembly

[kV]

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Secondary DistributionSwitchgear Type 8DH10

Fig. 99: Schemes and dimensions

2 3 2 3

Width

Depth

Height

500

780

2000

Individual panels

Ring-main panel Transformer panel Billing meteringpanel

Busbar meteringand grounding panel

Dimensions [mm]

350

780

1400

500

780

1400

600*/850

780

1400/2000**

500

780

1450

Width

Depth

Height

700

780

1400

Blocks

Ring-main feeders Ring-main feeders Transformer feeders

1050

780

1400

Transformer feeders

1000

780

1400

1500

780

1400

Dimensions [mm]

* Width for version with combined instrument transformer** With low-voltage compartment

Circuit-breaker panel

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Rated power-frequencywithstand voltage

Rated lightning-impulsewithstand voltage

Rated short-time current 1s

Rated short-circuitmaking current

Rated busbar current1)

Rated feeder current

Technical data (rated values)1)

Rated voltage andinsulation level

1) Higher values on request

7.2

[kV]

[kV]

[kA]

[kA]

[A]

[A]

20

60

20

50

630

630

12

28

75

20

50

630

630

17.5

38

95

16

40

630

630

24

50

125

16

40

630

630

Fig. 100: Extensible modulares switchgear type 8AA20

Load-breaker panels

Circuit-breaker panels

Metering panels

Dimensions Width Height Depth

12/24 kV[mm]

600/750

750/750

600/750

665/790 or 931/1131

931/1131

665/790 or 931/1131

2000

2000

2000

[mm]12/24 kV[mm]

Consumer substationmodular switchgeartype 8AA20, 7.2–24 kVextensible, air-insulated

Typical use

The air-insulated modular indoor switch-gear is used as a flexible system with a lotof panel variations. Panels with fused andunfused load-break switches, with truck-type vacuum circuit breakers and meteringpanels can be combined with air-insulatedbusbars.The 8AA20 ring-main units are type-tested,factory-assembled metal-enclosed indoorswitchgear installations. They meet opera-tional requirements by virtue of the follow-ing features:

Personnel safety

Sheet-steel enclosure tested for resist-ance to internal arcing

All switching operations with doorclosed

Testing for dead state with door closed Insertion of barrier with door closed

Safety, reliability/maintenance

Complete mechanical interlocking Preventive interlocking between barrier

and switch disconnector Door locking

Excellent resistance to ambientconditions

High level of pollution protection byvirtue of sealed enclosure in all operat-ing states

Insulators with high pollution-layerresistance

Standards

The switchgear complies with thefollowing standards:IEC-Publ. 56, 129, 256-1, 298,

420, 694VDE 0670 Part 2, 4 and 6

Part 101–107Part 301, 303Part 1000

In accordance with the harmonizationagreement reached by the EC memberstates, their national specifications con-form to IEC-Publ. No. 298.

Fig. 101

Fig. 102: Dimensions

Secondary DistributionSwitchgear Type 8AA20

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Fig. 103a: Cross section of cable feeder panel

1

2

1

2

34

Load-break switchGrounding switch

12

Vacuum circuit breakerCurrent transformerPotential transformerGrounding switch

1234

Fig. 104: Schemes

Secondary DistributionSwitchgear Type 8AA20

Resistance to internal arcing

– IEC-Publ. 298, Annex AA– VDE 0670, Part 6 and Part 601

Type of service location

Air-insulated ring-main units can be usedin service locations and in closed electricalservice locations in accordance withVDE 0101.

Specific features

Switch disconnector fixed-mounted Switch disconnector with integrated

central operating mechanism Standard program includes numerous

circuit variants Operations enabled by protective inter-

locks; the insulating barrier is included inthe interlocking

Extensible by virtue of panel design Cubicles compartmentalized (option) Minimal cubicle dimensions without

extensive use of plastics Lines up with earlier type 8AA10 Withdrawable circuit-breaker section can

be moved into the service and discon-nected position with the door closed

Individual panels

Scheme 11/12

Circuit-breaker panels

Scheme 13/14

Scheme 21/22

Load-breaker panels

Scheme 23/24 Scheme 25/26

Scheme 33/34

Metering and cable panels

Fig. 103b: Cross section of withdrawable typevacuum circuit-breaker panel

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Fig. 105: Steel-clad outdoor substation 8FB1 for rated voltages up to 24 kV and transformers up to 1000 kVA

Factory-assembledpackaged substationstype 8FB1 (example )

Factory-assembled transformer substationsare available in different designs and di-mensions. As an example of a typical sub-station program, type 8FB1 is shown here.Other types are available on request.The transformer substations type 8FB1with up to 1000 kVA transformer ratingsand 7.2–24 kV are prefabricated and facto-ry-assembled, ready for connection of net-work cables on site.Special foundation not necessary. Distribution substations for

public power supply Nonwalk-in type Switchgear operated with open substa-

tion doors

General features/Applications

Power supply for LV systems, especiallyin load centers for public supply

Power supply for small and mediumindustrial plants with existing HV sidecable terminations

Particularly suitable for installation atsites subject to high atmospheric humid-ity, hostile environment, and stringentdemands regarding blending of the sta-tion with the surroundings

Extra reliability ensured by SF6-insulatedring-main units type 8DJ, which requireno maintenance and are not affected bythe climate

Brief description

The substation housing consists of a tor-sion-resistant bottom unit, with a concretetrough for the transformer, embedded inthe ground, and a hot-dip galvanized steelstructure mounted on it. It is subdividedinto three sections: HV section, transform-er section and LV section. The lateral sec-tion of the concrete trough serves asmounting surface for the HV and LV cubi-cles and also closes off the cable entrycompartments at the sides. These com-partments are closed off at the bottom andfront by hot-dip galvanized bolted steelcovers.Four threaded bushes for lifting the com-plete substation are located in the floor ofthe concrete trough. The substations arearc-fault-tested in order to ensure person-nel safety during operation and for the pe-destrians passing by the installed substa-tion.

HV section (as an example):

8DJ SF6-insulated ring-main unit(for details please refer to RMU‘s page2/50–2/61)

Technical data:

Rated voltages and insulation levels7.2 kV 12 kV 15 kV 17.5 kV 24 kV60 75 95 95 125 kV (BIL)

Rating of cable circuits: 400 / 630 A Rating of transformer circuits: 200 A Degree of protection for HV parts: IP 65 Ambient temperature range:

–30°C/+55°C (other on request)

Transformer-section:

Oil-cooled transformer with ratings up tomax. 1000 kVA. The transformer is con-nected with the 8DJ10 ring-main unit bythree single-core screened 35 mm2 plasticinsulated cables. The connection is madeby means of right-angle plugs or standardair-insulated sealing ends possible at thetransformer side.

LV section:

The LV section can take various forms tosuit the differing base configurations. Theconnection to the transformer is made byparallel cables instead of bare conductors.Incoming circuit: Circuit breaker, fused loaddisconnector, fuses or isolating links.Outgoing circuits: Tandem-type fuses,load-break switches, MCCB, or any otherrequested systems.Basic measuring and metering equipmentto suit the individual requirements.

Secondary DistributionSwitchgear and Transformer Substations

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Fig. 106: Technical data, dimensions and weights

HV section:SF6-insulatedring-main unit(RMU)

High-voltagesection

Substationhousing type:

8FB17

H

Transformersection

T

Low-voltagesection

L

Transformer rating 1000 kVA

Overall dimensions,weights:LengthWidthHeight abovegroundHeight overallFloor areaVolumeWeight withouttransformer

[mm][mm][mm]

[mm][mm2][mm3]

[kg]

329013001650

21004.287.06approx. 2280

257021001650

21005.408.91approx. 2530

210021001650

21004.417.28approx. 2400

386015501700

23505.9810.17approx. 3400

312023001700

23507.1812.20approx. 3800

235023001700

23505.419.19approx. 3600

L H

H T L H T L T

8FB10 8FB11 8FB12 8FB15 8FB16

HL

H T L TH T L

630 kVA 630 kVA 630 kVA 1000 kVA 1000 kVA

Fig. 107: HV section:Compact substation 8FB with SF6-insulated RMU(two loop switches, one transformer feeder switchwith HRC fuses)

Fig. 108: Transformer section:Cable terminations to the transformer, as a example

Fig. 109: LV section:Example of LV distribution board

Secondary DistributionSwitchgear and Transformer Substations

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Medium-Voltage DevicesProduct Range

Devices formedium-voltage switchgear

With the equipment program for switch-gear Siemens can deliver nearly everydevice which is required in the medium-voltage range between 7.2 and 36 kV.Fig. 110 gives an overview about the avail-able devices and their main characteristics.All components and devices conform tointernational and national standards,as there are:

Vacuum circuit breakers

IEC 56 IEC 694 BS5311 DIN VDE 0670

Vacuum switches

IEC 265-1 DIN VDE 0670, Part 301in combination with Siemens fuses: IEC 420 DIN VDE 0670, Part 303

Vacuum contactors

IEC 470 DIN VDE 0660, Part 103 UL 347

Switch disconnectors

IEC 129 IEC 265-1 DIN VDE 0670, Part 2 DIN VDE 0670, Part 301

HV HRC fuses

IEC 282 DIN VDE 0670, Part 4

Current and voltage transformers

IEC 185, 186 DIN VDE 0414 BS 3938, 3941 ANSI C57.13

For further information please contact:

Fax: ++ 49 - 91 31 - 73 46 54

Fig. 110: Equipment program for medium-voltage switchgear

Short-timecurrent(3s)

[kA]

3AH

3AF3AG

Type Ratedvoltage

[kV]

Short-circuitcurrent

[kA]

Indoor and outdoorcurrent and voltagetransformers

Device

Indoor vacuumcircuit breaker

Outdoor vacuumcircuit breaker

Modular assembly setwith indoor VCB

Indoor vacuum switch

Indoor vacuumcontactor

Vacuum interrupter

Indoor switchdisconnector

Indoor disconnectingand grounding switch

HV HRC fuses

Fuse bases

Indoor post insulators,bushings

7.2 … 36

12, 36

7.2 … 15

7.2 … 24

3.6 … 12

7.2 … 40.5

7.2 … 24

7.2 … 36

7.2 … 36

7.2 … 36

3.6 … 36

12 … 36

3CG

3TL

VS

3CJ

3D

3GD

3GH

3FA

3M

13.1 … 63

25

25 … 44

12.5 … 72

31.5 … 80

13.1 … 63

25

25 … 44

16 … 20

8 (1s)

12.5 … 72

16 … 20 (1s)

16 ... 63 (1s)

44peak withstandcurrent

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Medium-Voltage DevicesProduct Range

PageRatedcurrent

[A]

2/68

2/72

2/73

2/74

2/76

2/77

2/78

2/79

2/80

2/80

2/81

2/82

mechanical

Applications/remarksOperating cycles

All applications, e.g. overhead lines, cables, transformers,motors, generators, capacitors, filter circuits, arc furnaces

All applications, e.g. overhead lines, cables, transformers,motors, generators, capacitors, filter circuits

Original equipment manufacturer (OEM) and retrofit

All applications, e.g. overhead lines, cables, transformers,motors, capacitors; high number of operations; fusesnecessary for short-circuit protection

All applications, especially motors with very high numberof operating cycles

For circuit breakers, switches and gas-insulated switchgear

Small number of operations, e.g. distribution transformers

Protection of personnel working on equipment

Short-circuit protection; short-circuit current limitation

Accommodation of HV HRC fuse links

Insulation of live parts from another,carrying and supporting function

Measuring and protection

with ratedcurrent

with short-circuit current

25 … 100

30 … 50

25 … 100

10,000 …30,000

10,000

10,000

0.25x105 ... 2x106

10,000 …30,000

800 … 4000

1600

1250 … 3150

800

400 … 450

800 … 4000

630

400 … 2500

6.3 … 250

400

20

1000

10,000 …120,000

10,000

10,000

1x106 ... 3x106

10,000 …30,000

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Indoor vacuum circuit breakerstype 3AH

The 3AH vacuum circuit breakers arethree-phase medium-voltage circuit break-ers for indoor installations.As standard circuit breakers they are avail-able for the entire medium-voltage range.Circuit breakers with reduced pole centerdistances, circuit breakers for very highnumbers of switching cycles and single-phase versions are part of the program.The following breaker types are available: 3AH1 – the maintenancefree circuit

breaker which covers the rangebetween 7.2 kV and 24 kV. It hasa lifetime of 10,000 operating cycles

3AH2 – the circuit breaker for 60,000operating cycles in the range between7.2 kV and 24 kV

3AH3 – the maintenancefree circuitbreaker for high breaking capacities inthe range between 7.2 kV and 36 kV.It has a lifetime of 10,000 operatingcycles

3AH4 – the circuit breaker for up to120,000 operating cycles

3AH5 – the economical circuit breaker inthe lower range for 10,000 maintenance-free operating cycle

The 3AH circuit breakers are suitable for: Rapid load transfer, synchronization Automatic reclosing up to 31.5 kA Breaking short-circuit currents with

very high initial rates of rise of the recov-ery voltage

Switching motors Switching transformers and reactors Switching overhead lines and cables Switching capacitors Switching arc furnaces

Fig. 111: The complete 3AH program

Rated short-circuit breakingcurrent [kA]

7.2

12

15

17.5

24

36

13.1 16 20 25 31.5 40 50 63

800 800-1250

800-2500

800-1250

1250-3150

1250-4000

1250-2500

–-2500

Rated voltage[kV]

3AH1 3AH2 3AH3 3AH4 3AH5

800-1250

800-1250

1250-3150

Rated current[A]

Medium-Voltage DevicesType 3AH

Properties of 3AH circuit breakers:

No relubrication

Nonwearing material pairs at the bearingpoints and nonaging greases make relubri-cation superfluous on 3AH circuit breakersup to 10,000 operating cycles, even afterlong periods of standstill.

High availability

Continuous tests have proven that the3AHs are maintenancefree up to 10,000operating cycles: accelerated temperature/humidity change cycles between –25 and+60 °C prove that the 3AH functions relia-bly without maintenance.

Assured quality

Exemplary quality control with some hun-dred switching cycles per circuit breaker,certified to DIN/ISO 9001.

No readjustment

Narrow tolerances in the production ofthe 3AH permanently prevent impermissi-ble play: even after frequent switchingthe 3AH circuit breaker does not need tobe readjusted up to 10,000 operatingcycles.

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Fig. 112: Vacuum circuit breakers type 3AH

Fig. 113: Front view of vacuum circuit breaker 3AH1 with 160-mm pole center distance. Available up to 17.5 kV

Medium-Voltage DevicesType 3AH

Advantages of thevacuum switching principle

The most important advantages of theprinciple of arc extinction in a vacuum havemade the circuit breakers a technically su-perior product and the principle on whichthey work the most economical extinctionmethod available: Constant dielectric:

In a vacuum there are no decompositionproducts and because the vacuum inter-rupter is hermetically sealed there areno environmental influences on it.

Constant contact resistance:The absence of oxidization in a vacuumkeeps the metal contact surface clean.For this reason, contact resistance canbe guaranteed to remain low over thewhole life of the equipment.

Large total current:Because there is little burning of con-tacts, the rated normal current can beinterrupted up to 30,000 times, theshort-circuit breaking current an averageof 50 times

Small chopping current:The chopping current in the Siemensvacuum interrupter is only 4 to 5 A dueto the use of a special contact material.

High reliability:The vacuum interrupters need no seal-ings as conventional circuit breakers.This and the small number of movingparts inside makes it extremely reliable.

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Fig. 114a: Dimensions of typical vacuum circuit breakers type 3AH (Examples)

604532

210 210

520

190

105

437 473

60

604538

210 210

565

109

437583

105

190550

275 275662708 565

190

105

437535

60

Dimensions in mm

Dimensions in mm

Dimensions in mm

20 kA, up to 1250 A25 kA, up to 1250 A

3AH1,12 kV

16 kA, up to 1250 A,20 kA, up to 1250 A,25 kA, up to 1250 A

3AH1,24 kV

31.5 kA, 2500 A,40 kA, 2500 A

3AH1, 3AH2,12 kV

Medium-Voltage DevicesType 3AH

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708 595670

275275190

105

437

109

610

648

211 483

564 733

750275 275

25 kA, 2500 A

63 kA, 4000 A

3AH3,12 kV

31.5 kA, 2500 A,40 kA, 2500 A

3AH1, 3AH2,24 kV

3AH3, 3AH4,36 kV

776

820350 350

853

526211

612

564 1000791

Dimensions in mm

Dimensions in mm

Dimensions in mm

Medium-Voltage DevicesType 3AH

Fig. 114b: Dimensions of typical vacuum circuit breakers type 3AH (Examples)

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Outdoor vacuum circuitbreakers type 3AF and 3AG

The Siemens outdoor vacuum circuitbreakers are structure-mounted, easy-to-install vacuum circuit breakers for use insystems up to 36 kV. The pole construc-tion is a porcelain-clad construction similarto conventional outdoor high-voltageswitchgear. The triple-pole circuit breakeris fitted with reliable and well proven vacu-um interrupters. Adequate phase spacingand height have been provided to meetstandards and safety requirements.It is suitable for direct connection to over-head lines.The type design incorporates a minimumof moving parts and a simplicity of assem-bly assuring a long mechanical and electri-cal life. All the fundamental advantages ofusing vacuum interrupters like low operat-ing energy, lightweight construction, vir-tually shockfree performance leading toease of erection and reduction in founda-tion requirements, etc. have been retained.The Siemens outdoor vacuum circuitbreakers are designed and tested to meetthe requirements of IEC 56/IS 13118.

Advantages at a glance

High reliability Negligible maintenance Suitable for rapid autoreclosing duty Long electrical and mechanical life Completely environmental-friendly

Fig. 115: Outdoor vacuum circuit breakertype 3AF for 36 kV

Fig. 117: Dimensions of outdoor circuit breaker type 3AF for 36 kV

Fig. 116: Ratings for outdoor vacuum circuit breakers

12Rated voltage

Rated frequency

Rated lightning-impulse withstand voltage

Rated power-frequencywithstand voltage (dry and wet)

Rated short-circuitbreaking current

Rated short-circuitmaking current

Rated current

75

28

25

63

1600

50/60

36

170

70

25

Type 3AG

Technical data

Type 3AFVacuum circuit-breaker type

50/60

63

1600

[kV]

[Hz]

[kV]

[kV]

[kA]

[kA]

[A]

1830

1217

725 725190

19301730

650450

31052510

3710 3748

285 285

Front view Side view

Dimensions in mm

Medium-Voltage DevicesType 3AF/3AG

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Modular assembly sets withindoor vacuum circuit breakers

The modular assembly sets are especiallysuitable for retrofit applications and for theuse by original equipment manufacturers(OEM).The withdrawable assembly sets consist ofparts of type-tested, metal-clad, air-insulat-ed medium-voltage primary distributionswitchgear. The circuit-breaker compart-ment can be integrated in the completebay as individually required.The centerpiece of the set is a medium-voltage vacuum circuit breaker, incorporat-ing all benefits of vacuum switchgeartechnology: High reliability Negligible maintenance Long electrical and mechanical life Completely environment-friendly Suitable for all switching dutiesUse of these parts allows the OEM to uti-lize Siemens know-how in the constructionof air-insulated switchgear, with all the con-sequent advantages, such as: Components type-tested to IEC, devel-

oped and manufactured to DIN/ISO 9001 Maximum flexibility in the manufacturing

process Wide product range

Ratingsfor withdrawable truck shown in Fig. 118

7.2 kV to 15 kV rated voltage1250 A to 3150 A rated current25 kA to 44 kA rated short-circuit

breaking current

Fig. 118: Withdrawable truck with vacuum circuit breaker (Example)

Medium-Voltage DevicesModular Assembly Sets

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Indoor vacuum switchestype 3CG

The 3CG vacuum switches are multipur-pose switches conforming to IEC 265-1and DIN VDE 0670 Part 301.With these, all loads can be switched with-out any restriction and with a high degreeof reliability. The electrical and mechanicaldata are greater than for conventionalswitches. A rated current of 800 A, forexample, can be interrupted 10,000 timeswithout maintenance.The operating mechanism needs to belubricated only every 10 years.The vacuum switch is therefore extremelyeconomical.Vacuum switches are suitable for thefollowing switching duties: Overhead lines Cables Transformers Motors Capacitors Switching under ground-fault conditions

3CG switches can be combined with allSiemens fuses (250 A) and comply withthe specifications of IEC 420 andDIN VDE 0670 Part 303.

Fig. 119: Ratings for vacuum switches type 3CG

Fig. 120: Vacuum switch type 3CG for 24 kV, 800 A

Medium-Voltage DevicesType 3CG

Rated voltage U

Rated lightning-impulsewithstand voltage Ul,

Rated short-circuit makingcurrent I ma

Rated short-time current I m (3s)

Rated normal current I n

Rated ring-main breakingcurrent I c 1

Rated transformer breaking current

Rated capacitor breaking current

Rated cable-chargingbreaking current I c

Rated breaking current forstalled motors I d

Inductive switching capacity(cos ϕ ≤ 0.15)

Switching capacity underground fault conditions:– Rated ground fault breaking current I e– Rated cable-charging breaking current– Rated cable charging breaking current with superimposed load current

Number of switching cycles with I n

[kV]

[kV]

[kA]

[kA]

[A]

[A]

[A]

[A]

[A]

[A]

[A]

[A][A]

[A]

Technical data

12

75

50

20

800

800

10

800

63

1600

1600

63063

63+800

10,000

15

95

50

20

800

800

10

800

63

1250

1250

63063

63+800

10,000

24

125

40

16

800

800

10

800

63

1250

63063

63+800

10,000

7.2

60

50

20

800

800

10

800

63

2500

2500

63063

63+800

10,000

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Fig. 121: Dimensions of vacuum switch type 3CG (Examples)

7.2 and 12 kV switch

24 kV switch

630

275 275

379

684

708

537

435

43170

597

530

264

210 210

568

592

435

43170

492

482

Dimensions in mm

Dimensions in mm

Medium-Voltage DevicesType 3CG

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280 mm

325 mm

340 mm

Fig. 122: Vacuum contactor type 3TL6 for fixedmounting

Vacuum contactorsType 3TL

The three-pole vacuum contactors type3TL are for medium-voltage systems be-tween 3.6 kV and 12 kV and incorporate asolenoid-operated mechanism for highswitching frequency and unlimited closingduration.They are suitable for the opera-tional switching of AC devices in indoorsystems and can perform, for example, thefollowing switching duties: Switching of three-phase motors in

AC-3 and AC-4 operation Switching of transformers Switching of capacitors Switching of ohmic loads

(e.g. arc furnaces)

3TL vacuum contactors have the followingfeatures: Small dimensions Long electrical life

(up to 106 operating cycles) Maintenancefree Vertical or horizontal mounting

The vacuum contactors comply with thestandards for high-voltage AC contactorsbetween 1 kV and 12 kV according to IECPublication 470-1970 and DIN VDE 0660Part 103.3TL contactors also comply with ULStandard 347.

The vacuum contactors are available indifferent designs: Type 3TL6 with compact dimensions

and an electrical lifetime of 1x106 operat-ing cycles

Type 3TL8 with slender design and anelectrical lifetime of 0.25x106 operatingcycles

In the withdrawable unit, the 3TL6 vacuumcontactor can be grouped together andelectrically connected with fuse carriers forHV HRC fuse links according to DIN/BSand also with overvoltage limiters.

Fig. 123: Vacuum contactor type 3TL6 mounted onwithdrawable unit

Fig. 124: Ratings for vacuum contactors type 3TL

Medium-Voltage DevicesType 3TL

Fig. 125: Vacuum contactor type 3TL8 for fixedmounting

780 mm

1200 mm

605 mm

390 mm

375 mm

220 mm

Rated voltage Ue

Rated frequency

Rated normal current I e

Switching capacity according toutilization category AC-4 (cos ϕ = 0.35)Rated making currentRated breaking current

Mechanical life of the contactorswitching cycles

Mechanical life of the vacuuminterrupter – switching cycles

Electrical life of the vacuum interrupter(switching cycles with rated current)

Vacuum contactor type

[kV]

[Hz]

[A]

[A]

Technical data

12

3TL 65

7.2

3TL 61

3.6

50/60

45003600

3TL 60

7.2

50/60

40003200

3TL 81

450 400

1 x 106

1 x 106

1 x 106

3 x 106

2 x 106

1 x 106

3 x 106

2 x 106

1 x 106

1 x 106

0.25 x 106

0.25 x 106

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Medium-Voltage DevicesType VS

Vacuum interrupters

Vacuum interrupters for the medium-volt-age range are available from Siemens forall applications on the international marketfrom 1 kV up to 40.5 kV.

Applications

Vacuum circuit breakers Vacuum switches Vacuum contactors Transformer tap switches Circuit breakers for railway applications Autoreclosers Special applications, e.g. in nuclear

fusion

Compact design

Vacuum interrupters providea very high switching capacity within verycompact dimensions: e.g. vacuum inter-rupters for 15 kV/40 kA with housingdimensions of 125 mm diameter by168 mm length or for 12 kV/12.5 kA with68 mm diameter by 124 mm length.

Consistant quality assurance

Complete quality assurance (TQM andDIN/ISO 9001), rigorous material checkingof every delivery and 100% tests of theinterrupters for vacuum sealing guaranteereliable operation and the long life ofSiemens vacuum interrupters.

Environmental protection

In the manufacture of our vacuum inter-rupters we only use environmentally com-patible materials, such as copper, ceramicsand high-grade steel.The manufacturing processes do not dam-age the environment. For example, noCFCs are used in production (fulfilling theMontreal agreement), the components arecleaned in a ultrasonic cleaning plant.During operation vacuum interrupters donot affect the environment and are them-selves not affected by the environment.

Know-how for special applications

If necessary, Siemens is prepared to sup-plement our wide standard program byway of tailored, customized concepts.

Fig. 126: Vacuum interrupters from 1 kV to 40.5 kV

Fig. 127: Range of ratings for vacuum interrupters

Interrupters for vacuum circuit breakers

Un

In

Isc

7.2 kV – 40.5 kV

800 A – 4000 A

12.5 kA – 72 kA

Interrupters for vacuum contactors

Un

In

1 kV – 12 kV

450 A

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Technical data

7.2

20

50

630

Rated voltage

Rated short-timecurrent

Rated short-circuitmaking current

Rated normal current

[kV]

[kA]

[kA]

[A]

12

20

50

630

15

16

40

630

24

16

40

630

Switch disconnectorstype 3CJ1

Indoor switch disconnectors type 3CJ1 aremultipurpose types and meet all the rele-vant standards both as the basic versionand in combination with (make-proof)grounding switches.The 3CJ1 indoor switch-disconnectorshave the following features: A modular system with all important

modules such as fuses, (make-proof)grounding switches, motor operatingmechanism, shunt releases and auxiliaryswitches

Good dielectric properties even underdifficult climatic conditions because ofthe exclusive use of standard post insu-lators for insulation against ground

No insulating partitions even with smallphase spacings

Simple maintenance and inspection

Fig. 128: Switch disconnector type 3CJ1

Fig. 129: Ratings for switch disconnectors type 3CJ1

Medium-Voltage DevicesType 3CJ1

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Medium-Voltage DevicesType 3D

Technical data

12

16 to 63

40 to 160

400 to 2500

Rated voltage

Rated short-timecurrent

Rated short-circuitmaking current

Rated normal current

[kV]

[kA]

[kA]

[A]

24

16 to 31.5

40 to 80

630 to 2500

36

20 to 31.5

50 to 80

630 to 2500

Fig. 130: Disconnecting switch type 3DC

Disconnecting and groundingswitches type 3D

Disconnecting and grounding switchestype 3D are suitable for indoor installationsfrom 12 kV up to 36 kV.Disconnectors are mainly used to protectpersonnel working on equipment and musttherefore be very reliable and safe.This is assured even under difficult climaticconditions.Disconnecting and grounding switchestype 3D are supplied with a manual ormotor drive operating mechanism.

Fig. 131: Ratings for disconnectors type 3DC

Fig. 132: Ratings for grounding switches type 3DE

Technical data

12

20 to 63

50 to 160

Rated voltage

Rated short-timecurrent

Rated peakwithstand current

[kV]

[kA]

[kA]

24

20 to 31.5

50 to 80

36

20 to 31.5

50 to 80

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HV HRC fusestype 3GD

HV HRC (high-voltage high-rupturing-capac-ity) fuses are used as a short-circuit protec-tion in high-voltage switchgear. They pro-tect switchgear and components, such astransformers, motors, capacitors, voltagetransformers and cable feeders, from thedynamic and thermal effects of high short-circuit currents by breaking them as theyoccur.The HV HRC fuse links can only be usedto a limited degree as overload protectionbecause they only operate with certaintywhen their minimum breaking current hasalready been exceeded. Up to this currentthe integrated thermal striker prevents athermal overload on the fuse when used incircuit breaker/fuse combinations.Siemens HV HRC fuse links have the fol-lowing features: Use in indoor and outdoor installations Nonaging because the fuse element

is made of pure silver Thermal tripping Absolutely watertight Low power lossWith our 30 years of experience in themanufacture of HV HRC fuse links andwith production and quality assurancethat complies with DIN/ISO 9001,Siemens HV HRC fuse links meet thetoughest demands for safety and reliability.

Fuse-bases type 3GH

3GH fuse bases are used to accomodateHV HRC fuse links in switchgear.These fuse bases are suitable for: Indoor installations High air humidity Occasional condensation3GH HV HRC fuse bases are available assingle-phase and three-phase versions.On request, a switching state indicatorwith an auxiliary switch can be installed.

Fig. 134: Ratings for HV HRC fuse links type 3GD

Fig. 133: HV HRC fuse type 3GD

Fig. 135: Fuse bases type 3GH with HV HRC fuse links

Fig. 136: Ratings for fuse bases type 3GH

Technical data

7.2

63 to 80

6.3 to 250

Rated voltage

Rated short-circuitbreaking current

Rated normal current

[kV]

[kA]

[A]

12

40 to 63

6.3 to 160

24

31.5 to 40

6.3 to 100

36

31.5

6.3 to 40

Technical data

3.6/7.2

44

400

Rated voltage

Peak withstandcurrent

Rated current

[kV]

[kA]

[A]

12

44

400

24

44

400

36

44

400

Medium-Voltage DevicesType 3GD/3GH

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Fig. 140: The principle of capacitive voltage indication with the 3FA4 divider post insulator

Medium-Voltage DevicesInsulators and Bushings

Insulators:Post insulators type 3FAand bushings type 3FH/3FM

Insulators (post insulators and bushings)are used to insulate live parts from one an-other and also fulfill mechanical carryingand supporting functions.The materials for insulators are variouscast resins and porcelains. The use ofthese materials, which have proved them-selves over many years of exposure to theroughest operating and ambient conditionsand the high quality standard to DIN/ISO9001, assure the high degree of reliabilityof the insulators.Special ribbed forms ensure high electricalstrength even when materials are deposit-ed on the surface and occasional conden-sation is formed.Post insulators and bushings are manufac-tured in various designs for indoor and out-door use depending on the application.Innovative solutions, such as the 3FA4divider post insulator with an integratedexpulsion-type arrester, provide optimumutility for the customer.Special designs are possible if requestedby the customer.

Fig. 137: Draw-lead bushing type 3FH5/6

Fig. 138: Post insulators type 3FA1/2

C1

V C2

M

A

L

U

U1

U2

LUU1

U2

ConductorOperating voltagePartial voltageacross C1Partial voltage acrossC2 and indicator

C1C2

VAM

Coupling capacitanceUndercapacitance

ArresterIndicatorMeasuring socket

12

65 to90

35 to50

3.75 to25

3.6

60 to65

27 to40

3.75 to16

24

100 to145

55 to75

3.75 to25

36

145 to190

75 to105

3.75 to16

Technical data

Normal voltage

Lightning-impulsewithstand voltage

Rated power-frequencywithstand voltage

Minimum failing load

[kV]

[kV]

[kV]

[kN]

Fig. 139: Ratings for post insulators type 3FA1/2

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Technical data

12

10 to2500

80

Rated voltage

Primary ratedcurrent

Max. thermal ratedshort time current

Sec. thermallimit current

Current transformers Voltage transformers

[kV]

[A]

[kA]

[A]

24

10 to2500

80

36

10 to2500

80

12

5 to 10

24

5 to 13

36

8 to 17

Current and voltagetransformers type 4M

Measuring transformers are electricaldevices that transform primary electricalquantities (currents and voltages) to pro-portional and in-phase quantities which aresafe for connected equipment and operat-ing personnel.The indoor post insulator current and volt-age transformers of the block type haveDIN-conformant dimensions and are usedin air-insulated switchgear. A maximum ofoperational safety is assured even underdifficult climatic conditions by the use ofcycloalyphatic resin systems and provencast-resin technology.Special customized versions (e.g. up to3 cores for current transformers, switcha-ble windings, capacitance layer for voltageindication) can be supplied on request.The program also includes cast-resin insu-lated-bushing current transformers andoutdoor current and voltage transformers.

Fig. 143: Ratings for current and voltage transformers

Fig. 141: Block current transformer type 4MA

Fig. 142: Outdoor voltage transformer type 4MS4

Medium-Voltage DevicesType 4M

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Low-Voltage SwitchboardsSIVACON

Contents Page

Introduction 3/2

Advantages 3/2

Technical data 3/3

Cubicle design 3/4

Busbar system 3/5

Installation designs 3/6

Circuit-breaker design 3/6

Withdrawable-unit design 3/7–3/12

Contents Page

Fixed-mounted design 3/13–3/14

Frame and enclosure 3/15

Forms of internal separation 3/16

Installation details 3/17–3/18

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General

The SIVACON low-voltage switchboardis an economical, practical and type-testedswitchgear and controlgear assembly(Fig. 3), used for example in power engi-neering, in the chemical, oil and capitalgoods industries and in public and privatebuilding systems.It is notable for its good availability andhigh degree of personnel and systemsafety. It can be used on all power levelsup to 6300 A: As main switchboard (power control

center or main distribution board) As motor control centre As subdistribution board.With the many combinations that theSIVACON modular design allows, a widerange of demands can be met both infixed-mounted and in withdrawable-unitdesign.All modules used are type-tested (TTA), i.ethey comply with the following standards: IEC 439-1 EN 60439-1 DIN VDE 0660 Part 500also DIN VDE 0106 Part 100

Certification DIN EN ISO 9001

Advantages of a SIVACONswitchboard

Type-tested standard modules Space-saving base areas from

400 x 400 mm2

Solid wall design for safe cubicle-to-cubicle separation

High packing density withup to 40 feeders per cubicle

Standard operator interface for allwithdrawable units

Test and disconnected positionwith door closed

Visible isolating gaps and pointsof contact

Alternative busbar positioningat top or rear

Cable/bar connection from aboveor below

Low-Voltage Switchboards

Introduction

Low-voltage switchboards form the linkbetween equipment for generation, trans-mission (cables, overhead lines) andtransformation of electrical energy on theone hand, and the loads, such as motors,solenoid valves, actuators and devicesfor heating, lighting and air conditioningon the other.As the majority of applications are suppliedwith low voltage, the low-voltage switch-board is of special significance in bothpublic supply systems and industrial plants.

Fig. 1: Typical low-voltage network in an industrial plant

Reliable power supplies are conditionalon good availability, flexibility for process-related modifications and high operatingsafety on the part of the switchboard.Power distribution in a system usuallycomes via a main switchboard (powercontrol center or main distribution board)and a number of subdistribution boardsor motor control centers (Fig. 1).

M M M M M M M M

LTETFT

Cable or busbar systemup to 4 MVAup to 690 V

up to 6300 A

3-50 Hz

up to 5000 A

Incoming circuit-breaker

Main switchboard

Circuit-breakers asfeeders to the sub-distribution boards

Connecting cables

Subdistributionboard e. g. services(Lighting, heating,air conditioning,etc.)

up to 100 A

Control

Motor control center 2in withdrawable-unitdesign for production/manufacturing

up to630 A

up to630 A

ET FT

LT

= Circuit-breaker design= Withdrawable-unit design= Fixed-mounted design

Motor control center 1in withdrawable-unitdesign for production/manufacturing

up to630 A

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Low-Voltage Switchboards

Fig. 3: SIVACON low-voltage switchboard

Technical data at a glance

Rated currentRated impulse withstand current (Ipk)Rated short-time withstand current (Icw)

Busbar currents (3- and 4-pole):

Rated insulation voltage (Ui)

Rated operational voltage (Ue)

1000 V

690 V

Horizontal main busbars

Vertical busbars

for circuit-breakers

for fixed-mounted design

for withdrawable-unit design

See horizontal busbars

up toup toup to

6300 A220 kA100 kA

Rated currentRated impulse withstand current (Ipk)Rated short-time withstand current (Icw)

Rated currentRated impulse withstand current (Ipk)Rated short-time withstand current (Icw)

Device rated

Circuit-breakersCable feedersMotor feeders

Power loss per cubicle with combinationof various cubicles (Pv)Degree of protection to DIN VDE 40050, IEC 529

* Mean value at simultaneity factor of all feeders of 0.6

up toup toup to

up toup toup to

2000 A

110 kA

50 kA

1000 A

110 kA

50 kA

up toup toup to

6300 A

800 kA

630 kA

IP 20 up to IP 54

approx. 600 W*

up to

Fig. 2

1 2 3

Circuit-breaker-design cubiclewith withdrawable circuit-breaker3WN, 1600 A

Withdrawable-unit-design cubiclewith 40 feeders ≤ 15 kW

Withdrawable-unit-design cubiclewith miniature and normalwithdrawable units up to 250 kW

1

2

3

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Dimensions in mm

Cable/busbar connection compartment

Cross-wiring compartment

Busbar compartmentDevice compartment

400 600

600 400 400 400 400

Low-Voltage Switchboards

Cubicle design

The cubicle is structured in modular gridbased on one modular spacing (1 M)corresponding to 175 mm. The effectivedevice installation space with a height of1750 mm therefore represents a heightof 10 M. The top and bottom space eachhas a height of 1 x 1M + 50 mm,i.e. 225 mm (Fig. 5).A cubicle is subdivided into four functioncompartments: Busbar compartment Device compartment Cable/busbar connection compartment Cross-wiring compartmentIn 400 mm deep cubicles, the busbar com-partment is at the top; in 600 mm deepcubicles it is at the rear. In double-frontsystems (1000 mm depth) and in a powercontrol center (1200 mm depth), the bus-bar compartment is located centrally.The switching device compartmentaccommodates switchgear and auxiliaryequipment.The cable/busbar connection compartmentis located on the right-hand side of the cu-bicle. With circuit-breaker design, however,it is below the switching device compart-ment (Fig. 4).The cross-wiring compartment is locatedat the top front and is provided for leadingcontrol and loop lines from cubicle tocubicle.

Fig. 4: Cubicle design

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Low-Voltage Switchboards

Busbar system

Together with the PEN or PE busbars,and if applicable the N busbars, the phaseconductor busbars L1, L2 and L3 formthe busbar system of a switchboard.One or more distribution busesand/or incoming and outgoing feederscan be connected to a horizontal mainbusbar. Depending on requirements,this main busbar passes through severalcubicles and can be linked with anothermain busbar via a coupling.A vertical distribution busbar is connectedwith the main busbar and suppliesoutgoing feeders within a cubicle.In a 400 mm deep cubicle (Fig. 5a) thephase conductors of the main busbar arealways at the top; the PEN or PE and Nconductors are always at the bottom.The maximum rated current at 35 °C is1965 A (non-ventilated), and 2250 A (venti-lated); the maximum short-circuit strengthis Ipk = 110 kA or Icw = 50 kA, respectively.In single-front systems with 600 mmcubicle depth (Fig. 5b), the main busbarsare behind the switching device compart-ment. In double-front systems of 1000 mmdepth (Fig. 5c), they are between the twoswitching device compartments (central).The phase conductors can be arranged atthe top or bottom; PEN, PE and N conduc-tors are always at the bottom. The maxi-mum rated current is at 35 °C 3250 A(non-ventilated) or 3500 A (ventilated);Ipk = 220 kA or Icw = 100 kA, respectively.In 1200 mm deep systems (power controlcenter) (Fig. 5d) the conductors arearranged as for double-front systems, butin duplicate; the phase conductors arealways at the top. The maximum ratedcurrent at 35 °C is 4850 A (non-ventilated)or 6000 A (ventilated); Ipk = 220 kA,Icw = 100 kA.

Fig. 5: Modular grid and location of main busbars

400

175

400 50

50

175

400

Top space Switching device compartment

Bottom space

50

400 50

175

2200

175

50

10 x175

200

175

50

2200 10 x175

2200

a) b)

d)c)

175

50

10 x175

175

175

50

10 x175

200 400 400400

Dimensions in mm

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Installation designs

The following designs are availablefor the duties specified: Circuit-breaker design Withdrawable-unit design Fixed-mounted design

Circuit-breaker design

Distribution boards for substantial energyrequirements are generally followed bya number of subdistribution boards andloads. Particular demands are thereforemade in terms of long-term reliability andsafety. That is to say, ”supply“, ”coupling“and ”feeder“ functions must be reliablyavailable over long periods of time. Mainte-nance and testing must not involve longstandstill times. The circuit-breaker designcomponents meet these requirements.The circuit-breaker cubicles have separatefunction spaces for a switching devicecompartment, auxiliary equipment com-partment and cable/busbar connectioncompartment (Fig. 7).The auxiliary equipment compartment isabove the switching device compartment.The cable or busbar connection compart-ment is located below. With supply fromabove, the arrangement is a like a mirrorimage. The cubicle width is determined bythe breaker rated current.

Low-Voltage Switchboards

Fig. 7: Circuit-breaker cubicle with withdrawable circuit-breaker 3WN, 1600 A rated current

Circuit-breaker design 3WN

The 3WN circuit-breakers in withdrawable-unit or fixed-mounted design are usedfor incoming supply, outgoing feeders andcouplings (longitudinal and transverse).The operational current can be shown onan LCD display in the control panel; thereis consequently no need for an ammeteror current transformer.

400600800

1000

Cubicle width

[mm]

IN to 1600IN to 2500IN to 3200IN to 6300

Breaker ratedcurrent[A]

Fig. 6

The high short-time current-carrying capaci-ty for time-graded short-circuit protection(up to 500 ms) assures reliable operationof sections of the switchboard not affectedby a short circuit.With the aid of short-time grading controlfor very brief delay times (50 ms), thestresses and damage suffered by a switch-board in the event of a short-circuit can besubstantially minimized, regardless of thepreset delay time of the switching deviceconcerned.The withdrawable circuit-breaker hasthree positions between which it can bemoved with the aid of a crank or spindlemechanism. In the connected position themain and auxiliary contacts are closed.

In the test position the auxiliary contactsare closed. In the disconnected positionboth main and auxiliary contacts are open.Mechanical interlocks ensure that, in theprocess of moving from one position toanother, the circuit-breaker always reachesthe OPEN state or that closing is notpossible when the breaker is betweentwo positions.The circuit-breaker is always moved withthe door closed. The actual position inwhich it is can be telecommunicated viaa signaling switch.A kit, switch or withdrawable unit canbe used for grounding and short-circuiting.

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Withdrawable-unit design

A major feature of withdrawable-unitdesign is removability and ease of replace-ment of equipment combinations underoperating conditions, i.e. a switchboardcan be adapted to process-related modifi-cations without having to be shut down.Withdrawable-unit design is used thereforemainly for switching and control of motors(Fig. 8).

Withdrawable units

The equipment of the main circuit of anoutgoing feeder and the relevant auxiliaryequipment are integrated as a function unitin a withdrawable unit, which can be easilyaccommodated in a cubicle.In basic state, all equipment and movableparts are within the withdrawable unit con-tours and thereby protected from damage.The facility for equipping the withdrawableunits from the rear allows plenty of spacefor auxiliary devices. Measuring instru-ments, indicator lights, pushbuttons, etc.are located on a hinged instrument panel,such that settings (e.g. on the overloadrelay) can be easily performed duringoperation.

Low-Voltage Switchboards

Fig. 8: High packing density with up to 40 feeders percubicle

Fig. 9: Size 1 withdrawable unit, 18.5 kW with contactor-type star-delta starter

A distinction is made between miniature(sizes 1/4 and 1/2) and normal withdraw-able units (sizes 1, 2, 3 and 4) (Fig. 9).The normal withdrawable unit of size 1has a height of one modular spacing(175 mm) and can, with the use of a mini-ature withdrawable unit adapter, be re-placed by 4 withdrawable units of size 1/4or 2 units of size 1/2. The withdrawableunits of sizes 2, 3 and 4 have a height of2, 3 and 4 modular spacings, respectively.The maximum complement of a cubicle is,for example, 10 full-size withdrawableunits of size 1 or 40 miniature withdrawa-ble units of size 1/4 .

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Low-Voltage Switchboards

Fig. 10: Withdrawable-unit principle

Moving isolating contact system

For main and auxiliary circuits the with-drawable units are equipped with a movingisolating contact system. It has contactson both the incoming and outgoing side;they can be moved by handcrank such thatthey come laterally out of the withdrawa-ble unit and engage with the fixed contactsin the cubicle. On miniature withdrawableunits the isolating contact system movesupwards into the miniature withdrawableunit adapter.A distinction is made between connected,disconnected and test position (Fig. 10)In the connected position both main andauxiliary contacts are closed; in the discon-nected position they are open. The testposition allows testing of the withdrawableunit for proper function in no-load (cold)state, in which the main contacts are open,but the auxiliary contacts are closed for theincoming control voltage.In all three positions the doors are closedand the withdrawable unit mechanicallyconnected with the switchboard.This assures optimal safety for personneland the degree of protection is upheld.Movement from the connected into thetest position and vice-versa always passesthrough the disconnected position; thisassures that all contactors drop out.

Operating error protection

Integrated maloperation protection ineach withdrawable unit reliably preventsmoving of the isolating contacts with themain circuit-breaker ”CLOSED“ (handcrankcannot be attached) (Fig. 11).

Fig. 11: Operating error protection prevents travel of the isolating contacts when the master switch is “ON”

Connected position

Disconnected position

Test position

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Low-Voltage Switchboards

Indicating and signaling

The current position of a withdrawableunit is clearly indicated on the instrumentpanel. Such signals as ”feeder not avail-able“ (AZNV), ”test“ and ”AZNV and test“can be given by additional alarm switches.The alarm switch in the compartment(S21) is a limit switch of NC design; thatin the withdrawable unit (S20) is of NOdesign. Both are actuated by the mainisolating contacts of the withdrawable unit(Fig. 12).

Fig. 12: Circuitry and position of main and auxiliary contacts

COM

AZNV

Test

X19 = Auxiliary isolating contactS20 = Alarm switch in withdrawable unit*S21 = Alarm switch in compartment*WU = Withdrawable unitCompt. = Compartment

*actuated by main isolating contact

Test

- X19

- S21

AZNV

- X19

- Q1 - S21

Compt.WU

AZNV/Test

- X19

- Q1 - S21- S20

Compt.WU Compt.WU

*No signal, as auxiliary isolating contact open

*

Main isolatingcontact

Aux. isolatingcontact

In with-drawable unit- S 201 S

In compartment

- S 211 Ö

Connected

Disconnected

Test

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Fig. 13: Arcing fault-protected plug-on bar systemembedded in the left of the cubicle

Vertical distribution bus(plug-on bus)

The vertical plug-on bus with the phaseconductors L1, L2 and L3 is located on theleft-hand side of the cubicle and featuressafe-to-touch tap openings (Fig. 13).The vertical PE, PEN and N busbars areon the right-hand side of the cubicle ina separate, 400 mm wide cable connectioncompartment, equipped with variable cablebrackets.

Rated currents – fused and withdraw-able unit sizes of cable feeders

Rated currents – non-fused and with-

drawable unit sizes of cable feeders

( ):Figures in brackets short-circuit-proof up to 100 kA*3VU13 with limiter short-circuit-proof up to 50 kA

Low-Voltage Switchboards

Fig. 14

I

D3063KL503KL523KL533KL553KL573KL61

3563

125160250400630

1/4 / 1/2112223

Device Ratedcurrent

With-drawableunitsize

Type [A]

Device

3VU13*3VU163VU133VU163VF13VF33VF43VF53VF6

2532 (25)25 (6)63 (32)63 (32)160250400630

1/4 / 1/21/21111224

Ratedcurrent

With-drawableunitsize

Type [A]

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Siemens Power Engineering Guide · Transmission & Distribution 3/11

Power ratings – fused and withdraw-able unit sizes of cable feeders

Low-Voltage Switchboards

Fig. 15

FVNR FVR Star-delta starters

400 V 500 V 690 V 400 V 500 V 690 V 400 V 500 V 690 V 400 V 500 V 690 V

Full-voltagenon-reversing (FVNR)motor startersNormal-duty start [kW]

Full-voltagenon-reversing (FVNR)motor startersHeavy-duty start [kW]

Full-voltagereversing (FVR)motor startersReversing circuit [kW]

Star-delta starters[kW]

Withdrawableunit size

–224590

160–

400500

1518.53775

160250

––

15224590

200355

1/41/212343+34+4

22223790

160500

–5.5

157590

160––

–7.5

2290

132200

–113790

132375

1118.53045

110250

––

11223755

132315

11223755

160375

–18.53755

132–

250355

–223055

160–

355–

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Siemens Power Engineering Guide · Transmission & Distribution3/12

I

FVNR Star-delta startersFVR

II

690 V

Withdrawableunit size

11113075

160250

33

3790

200315

––––––

–2.24

37160

––5.5

45200

––––––

111118.575

160250

33

2290

200315

––––––

400 V 500 V 690 V 400 V 500 V 400 V 500 V 690 V

––––––

1/41/21234

–111555

110200

–1.1

3775

132250

400 V 500 V 690 V

Full-voltagenon-reversing (FVNR)motor startersNormal-duty start [kW]

Full-voltagenon-reversing (FVNR)motor startersHeavy-duty start [kW]

Full-voltagereversing (FVR)motor startersReversing circuit [kW]

Star-delta starters[kW]

Withdrawableunit size

––––––

111118.575

160250

33

1590

200315

1/41/21234

–2.24

37160

––––––

41118.555

160250

1.13

1575

200315

––––––

–111555

110200

–1.1

1575

132250

–––––

––5.5

45200

400 V 500 V 690 V 400 V 500 V 690 V 400 V 500 V 690 V 400 V 500 V 690 V

Full-voltagenon-reversing (FVNR)motor startersNormal-duty start [kW]

Full-voltagenon-reversing (FVNR)motor startersHeavy-duty start [kW]

Full-voltagereversing (FVR)motor startersReversing circuit [kW]

Star-delta starters[kW]

––––––

Low-Voltage Switchboards

Power ratings – non-fused withoverload relay and withdrawable unit

Coordination type 1

Coordination type 2

Fig. 16

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Low-Voltage Switchboards

Fixed-mounted design

In certain applications, e.g. in buildinginstallation systems, either there is noneed to replace components underoperating conditions or short standstilltimes do not result in exceptional costs.In such cases the fixed-mounted design(Fig. 17) offers excellent economy, highreliability and flexibility by virtue of: Any combination of modular function

units Easy replacement of function units after

deenergizing the switchboard Brief modification or standstill times

by virtue of lateral vertical cubiclebusbars

Add-on components for subdivision andeven compartmentalization in accord-ance with requirements.

Modular function units

The modular function units enable versatileand efficient installation, above all when-ever operationally required changes or ad-aptations to new load data are necessary(Fig. 18). The subracks can be equipped asrequired with switching devices or combi-nations thereof; the function units can becombined as required within one cubicle.When the function modules are fitted inthe cubicle they are first attached in theopenings provided and then bolted to thecubicle. This securing system enablesuncomplicated ”one-man assembly“.

Vertical distribution bus (cubicle busbar)

The vertical cubicle busbar with the phaseconductors L1, L2 and L3 is fastened tothe left-hand side wall of the cubicle andoffers many connection facilities (withoutthe need for drilling or perforation) forcables and bars. It can be subdivided atthe top or bottom once per cubicle (forgroup circuits or couplings). The connec-tions are easily accessible and thereforeequally easy to check. A transparentshock-hazard protection allows visualinspection and assures a very high degreeof personnel safety.The vertical PE, PEN and N busbars are onthe right-hand side of the cubicle in a sepa-rate, up to 400 mm wide cable connectioncompartment, equipped with variable cablebrackets.

Fig. 17: Variable fixed-mounted design

Fig. 18: Fused modular function unit with direct protection, 45 kW

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Low-Voltage Switchboards

In-line-type switching devices

In-line-type switching devices allow space-saving installation of cable feeders ina cubicle and are particularly notable fortheir compact design (Fig. 19).

The in-line-type switching devices featureplug-in contacts on the incoming side.They are alternatively available for cablefeeders up to 630 A as: Fuse module Fuse-switch disconnectors

(single-break) Fuse-switch disconnectors

(double-break)with or without solid-state fuse monitoring Switch disconnectorsThe single- or double-break in-line-typeswitching devices allow fuse changingin dead state.The main switch is actuated by pullinga vertical handle to the side.The modular design allows quick reequip-ping and easy replacement of in-line-typeswitching devices under operating condi-tions.The in-line-type switching devices havea height of 50 mm, 100 mm or 200 mm.A cubicle can consequently be equippedwith up to 35 in-line-type switchingdevices.

Vertical distribution bus (plug-on bus)

The vertical plug-on bus with the phaseconductors L1, L2 and L3 is located at theback in the cubicle and can be additionallyfitted with a shock-hazard protection.The vertical PE, PEN and N busbars areon the right-hand side of the cubicle ina separate, 400 mm wide cable connectioncompartment, equipped with variable cablebrackets.

Fig. 19: Cubicle with in-line-type switching devices

Fig. 20: Rated currents and installation data of in-line-type switching devices

Device Ratedcurrent

In-line-type size

Type [A]

3NJ6110

3NJ6120

3NJ6140

3NJ6160

160

250

400

630

50

100

200

200

Height [mm]

Fuse-switch disconnector(single break)

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Low-Voltage Switchboards

Fig. 23: Cubicle dimensions and average weights

Fig. 22: Frame for rear busbarFig. 21: Frame for top busbar

Frame and enclosure

The galvanized SIVACON cubicle framesare of solid wall design and ensure reliablecubicle-to-cubicle separation.The enclosure is made of powder-coatedsteel sheets (Fig. 21 and 22).A cubicle front features one or more doors,depending on requirements and cubicletype. These doors are of 2 mm thick, pow-der-coated sheet steel and are hingedon the right or left (attached to the frame).Spring-loaded door locks prevent the doorsfrom flying open unintentionally, and alsoensure safe pressure equalization in theevent of an arcing fault.

Degree of protection (against foreignbodies/water, and personnel safety)

A distinction is made between ventilatedand non-ventilated cubicles.Ventilated cubicles are provided with slitsin the base space door and in the top plateand attain degree of protection in relationto the operating area of IP 20/21 orIP 40/41, respectively.Non-ventilated cubicles attain degreeof protection IP 54.In relation to the cable compartment,degree of protection IP 00 or IP 40, isgenerally attained.

Cubicle dimensions andaverage weights

2200 400500600800400500600800

10001000

400

600

1200

up to 1600up to 1600up to 1600up to 2000up to 1600up to 1600up to 2500up to 3150up to 4000up to 6300

300310320440315335440540700

1200

2200 1000 400600

1000

400450600

2200 1000 400600

1000

330380550

Height[mm]

Width[mm]

Depth[mm]

Rated current[A]

Withdrawable-unit design

Fixed-mounted design

Circuit-breaker design

Approx. weight[kg]

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Siemens Power Engineering Guide · Transmission & Distribution3/16

4b4a3b3a2b2a1

– – – – –

–––––

– – –

Circuit-breakerdesign

Form

With-drawable-unitdesign

Fixed-mounteddesign– modular– in-line

Low-Voltage Switchboards

Form of internal separation

in accordance to DIN VDE 0660 Part 500,7.7 (Fig. 25)Depending on requirements, the functioncompartments can be subdivided as perthe following table:

Fig. 25: Forms of internal separation to DIN VDE 0660 Part 500/EN 60 439-1/IEC 439-1

4

4

4

1

4

4

2 2

3 4 4

Form 4b

4

4

4

1

4

4

2 2

3 4 4

Form 4a

Form 3a

4

4

4

1

4

4

2 2

3 4 4

Form 3b

4

4

4

1

4

4

2 2

3 4 4

Form 2b

4

4

4

1

4

4

2 2

3 4 4

4

4

4

1

4

4

2 2

3 4 4

Form 2a

Form 1

4

4

4

1

4

4

2 2

3 4 4

1234

Functional unit

Terminal for external conductorsMain busbarBusbarIncoming circuitOutgoing circuit

Fig. 24

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Siemens Power Engineering Guide · Transmission & Distribution 3/17

400

900

600

1050

1000

1460

1200

1660

Cubicledepth

Transportbase depth

[mm]

[mm]

Low-Voltage Switchboards

Installation details

Transport units

For transport purposes, individual cubiclesof a switchboard are combined to forma transport unit, up to a maximum lengthof 2400 mm.The transport base is 200 mm longer thanthe transport unit and is 190 mm high. Thetransport base depth is:

Floor penetrations

The cubicles feature floor penetrationsfor leading in cables for connection, or foran incoming supply from below (Fig. 28).

Fig. 28: Floor penetrations

Cubicle width - 110

Cubicle depth 1000 mm, 1200 mm

Cubicle depth 400 mm

75

75

Cubicle depth 600 mm

Cubicle width - 110

215 400

75

Diameter 14.175

323

38.5

Cubicle width

Cubicle width - 110

523

250 600

75

Diameter 14.1

323

38.5

Cubicle width

Fastening forfloor mounting

Fastening forwall mounting

250

75

Diameter 14.1

38.5

Cubicle width

250

75

1000or1200

Cubicledepth - 77

Free space for cables andbar penetrations

Fig. 27

If the busbar is at the top, the main bus-bars between two transport units are con-nected via lugs which are bolted to thebusbar system.If the busbar is at the rear, the individualbars can be bolted together via connectionelements, as the conductors of theright-hand transport unit are offset to theleft and protrude beyond the cubicle edge.

Mounting

Cubicle depths 400 mm and 600 mm: Wall- or Floor-mountingCubicle depths 1000 mm and 1200 mm: Floor-mountingThe following minimum clearancesbetween the switchboard and anyobstacles must be observed:

There must be a minimum clearance of400 mm between the top and sides of thecubicle and any obstacles.

Clearences

Switchboard

75 mm100 mm 100 mm

Fig. 26

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Low-Voltage Switchboards

Operating and maintenance gangways

All doors of a SIVACON switchboard canbe fitted such that they close in the direc-tion of an escape route or emergency exit.If they are fitted differently, care must betaken that when doors are open, there isa minimum gangway of 500 mm (Fig. 29).In general, the door width must be takeninto account, i.e. a door must open throughat least 90°. (In circuit-breaker and fixed-mounted designs the maximum door widthis 1000 mm.)Installation gangways behind closed rearwalls call for a minimum width of 500 mm.If a lifting truck is used to install a circuit-breaker, the gangway widths must suit thedimensions of the lifting truck.

Fig. 29: Reduced gangways in area of open doors

Fig. 30

For further information please contact:

Fax: ++ 49 - 341- 447 0400

Min. gangway widthEscape route 600 or 700 mm

Free min. width500 mm1)

2)

20001)

600

7007002) 7002)

600

700

1) Minimum gangway height under covers or enclosures2) For installation gangways behind closed rear walls,

a width of 500 mm is acceptable

1) Where switchboard fronts face each other, narrowing of the gangwayas a result of open doors (i.e. doors that do not close in the directionof the escape route) is reckoned with only on one side

2) Note door widths, i.e. it must be possible to open the doorthrough at least 90°

Dimensions in mm

HeightWidthDepth

HeightWidthDepth

Dimensions of lifting truck [mm]

Minimum gangway width [mm]

Approx. 1500

2000680920

Page 153: 79667665 Siemens Power Engineering Guide Transmission Distribution

Transformers

Contents Page

Technical DataDistribution Transformers 4/13–4/17

Technical DataPower Transformers 4/18–4/23

On-load Tap Changers 4/24

Cast-resin Dry-typeTransformers, GEAFOL 4/25–4/28

Technical DataGEAFOL Cast-resinDry-type Transformers 4/29–4/32

Special Transformersand Reactors 4/33–4/34

Contents Page

Introduction 4/2

Product Range 4/3

Electrical Design 4/4–4/5

Transformer Loss Evaluation 4/6–4/7

Mechanical Design 4/8

Connection Systems 4/9– 4/10

Accessories andProtective Devices 4/11– 4/12

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4/2 Siemens Power Engineering Guide · Transmission & Distribution

Introduction

In addition, there are various special-purpose transformers such as convertertransformers, which can be both in therange of power transformers and in therange of distribution transformers as faras rated power and rated voltage are con-cerned.As special elements for network stabili-zation, arc-suppression coils and com-pensating reactors are available. Arc-sup-pression coils compensate the capacitivecurrent flowing through a ground fault andthus guarantee uninterrupted energy sup-ply. Compensating reactors compensatethe capacitive power of the cable networksand reduce overvoltages in case of loadrejection; the economic efficiency andstablility of the power transmission are im-proved.The general overview of our manufactur-ing/delivery program is shown in thetable ”Product Range“.

Standards and specifications, general

The transformers comply with the relevantVDE specifications, i.e. DIN VDE 0532”Transformers and reactors“ and the”Technical conditions of supply for three-phase transformers“ issued by VDEWand ZVEI.Therefore they also satisfy the require-ments of IEC Publication 76, Parts 1 to 5together with the standards and specifi-cations (HD and EN) of the EuropeanUnion (EU).Enquiries should be directed to the manu-facturer where other standards and spe-cifications are concerned. Only the US(ANSI/NEMA) and Canadian (CSA) stand-ards differ from IEC by any substantial de-gree, however, a design according to thesestandards is also possible.

Important additional standards

DIN 42 500, HD 428: oil-immersedthree-phase distribution transformers50–2500 kVA

DIN 42 504: oil-immersed three-phasetransformers 2–10 MVA

DIN 42 508: oil-immersed three-phasetransformers 12.5–80 MVA

DIN 42 523, HD 538: three-phasedry-type transformers 100–2500 kVA

DIN 45 635 T30: noise level IEC 289: reactance coils and neutral

grounding transformers IEC 551: measurement of noise level IEC 726: dry-type transformers RAL: coating/varnish

Transformers are one of the primarycomponents for the transmission anddistribution of electrical energy.Their design results mainly from the rangeof application, the construction, the ratedpower and the voltage level.The scope of transformer types starts withgenerator transformers and ends with dis-tribution transformers.Transformers which are directly connectedto the generator of the power station arecalled generator transformers. Their powerrange goes up to far above 1000 MVA.Their voltage range extends to approx.1500 kV.The connection between the different high-voltage system levels is made via networktransformers (network interconnectingtransformers). Their power range exceeds1000 MVA. The voltage range exceeds1500 kV.Distribution transformers are within therange from 50 to 2500 kVA and max.36 kV. In the last step, they distributethe electrical energy to the consumersby feeding from the high-voltage into thelow-voltage distribution network. Theseare designed either as liquid-filled or asdry-type transformers.Transformers with a rated power up to2.5 MVA and a voltage up to 36 kV arereferred to as distribution transformers;all transformers of higher ratings areclassified as power transformers.

0.05–2.5

2.5–3000

0.10–20

≤ 36

36-1500

≤ 36

Ratedpower

Max.operatingvoltage

[MVA] [kV]

Oildistributiontransformers

GEAFOL-cast-resintransformers

Powertransformers

4/13–4/17

4/18–4/23

4/29–4/32

Figs.onpage

Fig. 1: Transformer types

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4/3Siemens Power Engineering Guide · Transmission & Distribution

Product Range

100 kVA to more than 20 MVA, highest voltage for equipment up to 36 kV,of three- or single-phase designGEAFOL®-SL substations

Cast-resin distributionand power transformersGEAFOL

Above 2.5 MVA up to more than 1000 MVA, above 30 kV up to 1500 kV(system and system interconnecting transformers, with separate windings orauto-connected), with on-load tap changers or off-circuit tap changers,of three- or single-phase design

Generator and powertransformers

Furnace and converter transformersTraction transformers mounted on rolling stock and appropriate on-load tap-changersSubstation transformers for traction systemsTransformers for train heating and point heatingTransformers for: Electrostatic precipitators, high-frequency generating plants,electrophoresis and graphite producing plantsTransformers for HVDC transmission systemsStarting transformersTransformers for audio frequencies in power supply systemsThree-phase neutral electromagnetic couplers and grounding transformersTransformers for potentially explosive atmospheresIgnition transformers

Special transformersfor industry, tractionand HVDC transmissionsystems

50 to 2 500 kVA, highest voltage for equipment up to 36 kV,with copper or aluminum windings, hermetically sealed (TUMETIC®) orwith conservator (TUNORMA®) of three- or single-phase design

Oil-immerseddistribution transformers,TUMETIC, TUNORMA

Liquid-immersed shunt and current-limiting reactors up tothe highest rated powersReactors for HVDC transmission systemsStarting reactors, arc-suppression coils

Reactors

Buchholz relays, oil testing equipment,oil flow indicators and other monitoring devicesFan control cabinets, control cabinets for parallel operation andautomatic voltage controlSensors (PTC, Pt 100)

Accessories

Advisory services for transformer specificationsOrganization, coordination and supervision of transportationSupervision of assembly and commissioningService/inspection troubleshooting servicesTraining of customer personnelInvestigation and assessment of oil problems

Service

Fig. 2

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4/4 Siemens Power Engineering Guide · Transmission & Distribution

Dy1

iii

Dy5

Dy11

Yd1

Yd5

Yd11

ii

i

III II

I1

iiiii

iIII II

I

5

iiiii

i

III II

I11

iii

iii

III II

I11

iiiii

iIII II

I

5

iii

ii

i

III II

I1

Electrical Design

Power ratings and type of cooling

All power ratings in this guide are the pro-duct of rated voltage (times phase-factorfor three-phase transformers) and ratedcurrent of the line side winding (at centertap, if several taps are provided), expres-sed in kVA or MVA, as defined in IEC 76-1.If only one power rating and no coolingmethod are shown, natural oil-air cooling(ONAN or OA) is implied for oil-immersedtransformers. If two ratings are shown,forced-air cooling (ONAF or FA) in one ortwo steps is applicable.For cast resin transformers, natural aircooling (AN) is standard. Forced air cooling(AF) is also applicable.

Temperature rise

In accordance with IEC-76 the standardtemperature rise for oil-immersed powerand distribution transformers is: 65 K average winding temperature

(measured by the resistance method) 60 K top oil temperature

(measured by thermometer)The standard temperature rise for Siemenscast-resin transformers is 100 K (insulation class F) at HV and

LV winding.Whereby the standard ambient tempera-tures are defined as follows: 40 °C maximum temperature, 30 °C average on any one day, 20 °C average in any one year, –25 °C lowest temperature outdoors, –5 °C lowest temperature indoors.Higher ambient temperatures require acorresponding reduction in temperaturerise, and thus affect price or rated poweras follows: 1.5% surcharge for each 1 K above

standard temperature conditions, or 1.0% reduction of rated power for each

1 K above standard temperature condi-tions.

These adjustment factors are applicableup to 15 K above standard temperatureconditions.

Altitude of installation

The transformers are suitable for operationat altitudes up to 1000 meters above sealevel. Site altitudes above 1000 m necessi-tate the use of special designs and an in-crease/or a reduction of the transformerratings as follows (approximate values):

The primary winding (HV) is normallyconnected in delta, the secondary winding(LV) in wye. The electrical offset of thewindings in respect to each other is either30, 150 or 330 degrees standard (Dy1,Dy5, Dy11). Other vector groups aswell as single-phase transformers andautotransformers on request (Fig. 3).

Power transformers

Generator transformers and large powertransformers are usually connected in Yd.For HV windings higher than 110 kV, theneutral has a reduced insulation level.For star/star-connected transformers andautotransformers normally a tertiary wind-ing in delta, whose rating is a third of thatof the transformer, has to be added. Thisstabilizes the phase-to phase voltages inthe case of an unbalanced load and pre-vents the displacement of the neutralpoint.Single-phase transformers and autotrans-formers are used when the transportationpossibilities are limited. They will be con-nected at site to three-phase transformerbanks.

2% increase for every 500 m altitude (orpart there of) in excess of 1000 m, or

2% reduction of rated power for each500 m altitude (or part there of) in ex-cess of 1000 m.

Transformer losses and efficiencies

Losses and efficiencies stated in this guideare average values for guidance only. Theyare applicable if no loss evaluation figure isstated in the inquiry (see following chapter)and they are subject to the tolerances stat-ed in IEC 76-1, namely +10% of the totallosses, or +15% of each component loss,provided that the tolerance for the totallosses is not exceeded.If optimized and/or guaranteed losses with-out tolerances are required, this must bestated in the inquiry.

Connections and vector groups

Distribution transformers

The transformers listed in this guide areall three-phase transformers with one setof windings connected in star (wye) andthe other one in delta, whereby the neutralof the star-connected winding is fully ratedand brought to the outside.

Fig. 3: Most commonly used vector groups

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4/5Siemens Power Engineering Guide · Transmission & Distribution

Electrical Design

≤ 1.1

3.6

7.2

12.0

17.5

24.0

36.0

52.0

72.5

123.0

145.0

170.0

245.0

Highestvoltagefor equip-ment Um(r. m. s.)

[kV]

Ratedshort-durationpower-frequencywithstandvoltage(r. m. s.)

[kV]

Rated lightning-impulse with-stand voltage(peak)

List 1[kV]

List 2[kV]

3

10

20

28

38

50

70

95

140

185

230

275

325

360

395

20

40

60

75

95

145

40

60

75

95

125

170

250

325

450

550

650

750

850

950

Higher test voltage withstand requirements must bestated in the inquiry and may result in a higher price.

Fig. 4: Insulation level

Insulation level

Power-frequency withstand voltages andlightning-impulse withstand voltages are inaccordance with IEC 76-3, Para. 5, Table II,as follows:

Conversion to 60 Hz – possibilities

All ratings in the selection tables of thisguide are based on 50 Hz operation.For 60 Hz operation, the following optionsapply: 1. Rated power and impedance voltage

are increased by 10%, all other parame-ters remain identical.

2. Rated power increases by 20%, butno-load losses increase by 30% andnoise level increases by 3 dB, all otherparameters remain identical (this lay-out is not possible for cast-resin trans-formers).

3. All technical data remain identical,price is reduced by 5%.

4. Temperature rise is reduced by 10 K,load losses are reduced by 15%, allother parameters remain identical.

Overloading

Overloading of Siemens transformers isguided by the relevant IEC-354 ”Loadingguide for oil-immersed transformers“and the (similar) ANSI C57.92 ”Guide forloading mineral-oil-immersed power trans-formers“.Overloading of GEAFOL cast-resin trans-formers on request.

Routine and special tests

All transformers are subjected to thefollowing routine tests in the factory: Measurement of winding resistance Measurement of voltage ratio and check

of polarity or vector group Measurement of impedance voltage Measurement of load loss Measurement of no-load loss and

no-load current Induced overvoltage withstand test Seperate-source voltage withstand test Partial discharge test (only GEAFOL

cast-resin transformers).The following special tests are optional andmust be specified in the inquiry: Lightning-impulse voltage test (LI test),

full-wave and chopped-wave (specify) Partial discharge test Heat-run test at natural or forced cooling

(specify) Noise level test Short-circuit test.Test certificates are issued for all theabove tests on request.

Transformer cell (indoor installation)

The transformer cell must have the neces-sary electrical clearances when an open airconnection is used. The ventilation systemmust be large enough to fulfill the recom-mendations for the maximum tempera-tures according to IEC.For larger power transformers either anoil/water cooling system has to be used orthe oil/air cooler (radiator bank) has to beinstalled outside the transformer cell.In these cases a ventilation system hasto be installed also to remove the heatcaused by the convection of the transform-er tank.

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4/6 Siemens Power Engineering Guide · Transmission & Distribution

A. Capital cost

B. Cost of no-load loss

C. Cost of load loss

D. Cost resulting from demands charges

Cc =Cp · r

100

= purchase price

= depreciation factor

= interest factor

= interest rate in % p.a.= depreciation period in years

Cp

q = p100

r = p · qn

qn – 1

pn

CP0 = Ce · 8760 h/year · P0

= energy charges

= no-load loss [kW]

Ce

P0

amountkWh

CPk = Ce · 8760 h/year · α2 · Pk

amountyear

amountyear

amountyear

α

Pk

=

= copper loss [kW]

constant operation loadrated load

CD =amount

yearCd (P0 + Pk)

Cd = demand charges amountkW · year

Transformer Loss Evaluation

The sharply increased cost of electricalenergy has made it almost mandatory forbuyers of electrical machinery to carefullyevaluate the inherent losses of theseitems. In case of distribution and powertransformers, which operate continuouslyand most frequently in loaded condition,this is especially important. As an example,the added cost of loss-optimized trans-formers can in most cases be recoveredvia savings in energy use in less than threeyears.Low-loss transformers use more andbetter materials for their construction andthus initially cost more. By stipulating lossevaluation figures in the transformer in-quiry, the manufacturer receives the nec-essary incentive to provide a loss-opti-mized transformer rather than the low-cost model.Detailed loss evaluation methods fortransformers have been developed andare described accurately in the literature,taking the project-specific evaluation fac-tors of a given customer into account.The following simplified method for a quickevaluation of different quoted transformerlosses is given, making the following as-sumptions: The transformers are operated con-

tinuously The transformers operate at partial load,

but this partial load is constant Additional cost and inflation factors are

not considered Demand charges are based on 100%

load.The total cost of owning and operating atransformer for one year is thus defined asfollows: A. Capital cost Cc

taking into account the purchase priceCp, the interest rate p, and the depre-ciation period n

B. Cost of no-load loss CP0,based on the no-load loss P0, andenergy cost Ce

C. Cost of load loss Cpk,based on the copper loss Pk, the equi-valent annual load factor a, and energycost Ce

D. Demand charges Cd,based in the amount set by the utility,and the total kW of connected load.

These individual costs are calculated asfollows:

Fig. 5

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4/7Siemens Power Engineering Guide · Transmission & Distribution

Transformer Loss Evaluation

To demonstrate the usefulness of suchcalculations, the following arbitrary exam-ples are shown, using factors that canbe considered typical in Germany, andneglecting the effects of inflation on therate assumed:

A. Low-cost transformer B. Loss-optimized transformer

Depreciation periodInterest rateEnergy charge

Demand charge

Equivalent annual load factor

npCe

Cd

α

= 20 years= 12% p. a.= 0.25 DM/kWh

= 350

= 0.8

DMkW · yr

P0 = 2.6 kWPk = 20 kWCp = DM 25 000

P0 = 1.7 kWPk = 17 kWCp = DM 28 000

no-load lossload losspurchase price

no-load lossload losspurchase price

Cc25000 · 13.39

100

DM 3348/year

CP0 0.25 · 8760 · 2.6

DM 5694/year=

=

=

=

CPk 0.25 · 8760 · 0.64 · 20

DM 28 032/year=

=

CD 350 · (2.6 + 20)

DM 7910/year=

=

Total cost of owning and operating thistransformer is thus:

DM 44984.–/year

Cc28000 · 13.39

100

DM 3 749/year

CP0 0.25 · 8760 · 1.7

DM 3 723/year=

=

=

=

CPk 0.25 · 8760 · 0.64 · 17

DM 23 827/year=

=

CD 350 · (1.7 + 17)

DM 6 545/year=

=

Total cost of owning and operating thistransformer is thus:

DM 37 844.–/year

The energy saving of the optimized distribution transformer of DM 7140 per yearpays for the increased purchase price in less than one year.

Example: 1600 kVA distribution transformer

Depreciation factorr = 13.39

Fig. 6

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4/8 Siemens Power Engineering Guide · Transmission & Distribution

Mechanical Design

Fig. 9: Practically maintenancefree: transformer withthe TUPROTECT air-sealing system built into the con-servator

General mechanical designfor oil-immersed transformers:

Iron core made of grain-orientedelectrical sheet steel insulated on bothsides, core-type.

Windings consisting of copper sectionwire or copper strip. The insulationhas a high disruptive strength and istemperature-resistant, thus guaranteeinga long service life.

Designed to withstand short circuit forat least 2 seconds (IEC).

Oil-filled tank designed as tank withstrong corrugated walls or as radiatortank.

Transformer base with plain or flangedwheels (skid base available).

Cooling/insulation liquid: Mineral oilaccording to VDE 0370/IEC 296. Siliconeoil or synthetic liquids are available.

Standard coating for indoor installation.Coatings for outdoor installation andfor special applications (e.g. aggressiveatmosphere) are available.

Tank design andoil preservation system

Sealed-tank distribution transformers,TUMETIC®

In ratings up to 2500 kVA and 170 kV LIthis is the standard sealed-tank distributiontransformer without conservator and gascushion. The TUMETIC transformer isalways completely filled with oil; oil expan-sion is taken up by the flexible corrugatedsteel tank (variable volume tank design),whereby the maximum operating pressureremains at only a fraction of the usual.These transformers are always shippedcompletely filled with oil and sealed fortheir lifetime. Bushings can be exchangedfrom the outside without draining the oilbelow the top of the active part.The hermetically sealed system preventsoxygen, nitrogen, or humidity from contactwith the insulating oil. This improves theaging properties of the oil to the extentthat no maintenance is required on thesetransformers for their lifetime. Generallythe TUMETIC transformer is lower thanthe TUNORMA transformer. This designhas been in successful service since 1973.A special TUMETIC-Protection device hasbeen developed for this transformer.

Distribution transformers withconservator, TUNORMA®

This is the standard distribution transform-er design in all ratings. The oil level in thetank and the top-mounted bushings is keptconstant by a conservator vessel or expan-sion tank mounted at the highest point ofthe transformer. Oil-level changes due tothermal cycling affect the conservator only.The ambient air is prevented from directcontact with the insulating oil through oil-traps and dehydrating breathers.Tanks from 50 to approximately 4000 kVAare preferably of the corrugated steel de-sign, whereby the sidewalls are formed onautomatic machines into integral coolingpockets. Suitable spot welds and bracesrender the required mechanical stability.Tank bottom and cover are fabricated fromrolled and welded steel plate.Conventional radiators are available.

Power transformers

Power transformers of all ratings areequipped with conservators. Both the openand closed system are available.With the closed system ”TUPROTECT®“the oil does not come into contact with thesurrounding air. The oil expansion is com-pensated with an air bag. (This design isalso available for greater distribution trans-formers on request).The sealing bag consists of strong nylonbraid with a special double lining of ozonand oil-resistant nitrile rubber. The interiorof this bag is in contact with the ambientair through a dehydrating breather;the outside of this bag is in direct contactwith the oil.All tanks, radiators and conservators(incl. conservator with airbag) are designedfor vacuum filling of the oil.For transformers with on-load tap changersa seperate smaller conservator is neces-sary for the diverter switch compartment.This seperate conservator (without air bag)is normally an integrated part of the mainconservator with its own magnetic oil levelindicator.Power transformers up to 10 MVA arefitted with weld-on radiators and areshipped extensively assembled; shippingconditions permitting.Ratings above 10 MVA require detachableradiators with individual butterfly valves,and partial dismantling of components forshipment.All the usual fittings and accessories for oiltreatment, shipping and installation ofthese transformers are provided as stand-ard. For monitoring and protective devices,see the listing on page 4/11.

Fig. 8: 630 kVA, three-phase, TUNORMA20 kV ± 2.5 %/0.4 kV distribution transformer

Fig. 7: Cross section of a TUMETIC three-phasedistribution transformer

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4/9Siemens Power Engineering Guide · Transmission & Distribution

Connection Systems

Distribution transformers

All Siemens transformers have top-mount-ed HV and LV bushings according to DIN intheir standard version. Besides the openbushing arrangement for direct connectionof bare or insulated wires, three basic insu-lated termination systems are available:

Fully enclosed terminal box for cables(Fig. 11)

Available for either HV and LV side, or forboth. Horizontally split design in degreeof protection IP 44 or IP 54 (Totally en-closed and fully protected against contactwith live parts, plus protection against drip,splash, or spray water).Cable installation through split cable glandsand removable plates facing diagonallydownwards. Optional conduit hubs. Suit-able for single-core or three-phase cableswith solid dielectric insulation, with orwithout stress cones. Multiple cables perphase are terminated on auxiliary busstructures attached to the bushings. Re-moval of transformer by simply bendingback the cables.

Insulated plug connectors (Fig. 12)

For substation installations, suitableHV can be attached via insulatedelbow connectors in LI ratings up to170 kV.

Flange connection (Fig. 13)

Air-insulated bus ducts, insulated busbars,or throat-connected switchgear cubiclesare connected via standardized flanges onsteel terminal enclosures. These can ac-commodate either HV, LV, or both bush-ings. Fiberglass-reinforced epoxy partitionsare available between HV and LV bushingsif flange/flange arrangements are chosen.The following combinations of connectionsystems are possible besides open bush-ing arrangements:

Cable box

Cable box

Flange

Flange

Elbow connector

Elbow connector

HV

Cable box

Flange/throat

Cable box

Flange/throat

Cable box

Flange/throat

LV

Fig 13: Flange connection for switchgear andbus ducts

Fig. 10: Combination of connection systems

Fig. 11: Fully enclosed cable connection box

Fig. 12: Grounded metal-elbow plug connectors

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4/10 Siemens Power Engineering Guide · Transmission & Distribution

Connection Systems

Power transformers

The most frequently used type of connec-tion for transformers is the outdoor bush-ing.Depending on voltage, current, systemconditions and transport requirements, thetransformers will be supplied with bush-ings arranged vertically, horizontally or in-clined. Up to about 110 kV it is usual touse oil-filled bushings according to DIN;condenser bushings are normally used forhigher voltages.Limited space or other design considera-tions often make it necessary to connectcables directly to the transformer. For volt-ages up to 30 kV air-filled cable boxes areused. For higher voltages the boxes areoil-filled. They may be attached to the tankcover or to its walls (Fig. 14).The space-saving design of SF6-insulatedswitchgear is one of its major advantages.The substation transformer is connecteddirectly to the SF6 switchgear. This elimi-nates the need for an intermediate link(cable, overhead line) between transform-er and system (Fig. 15).

Fig. 14: Transformers with oil-filled HV cable boxes

Fig. 15: Direct SF6-connection of the transformer to the switchgear

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4/11Siemens Power Engineering Guide · Transmission & Distribution

Accessories and Protective DevicesAccessories not listed completely.Deviations are possible.

Fig. 16: Double-float Buchholz relay

Fig. 17: Dial-type contact thermometer

Double-float Buchholz relay (Fig. 16)

For sudden pressure rise and gas detec-tion in oil-immersed transformer tanks withconservator. Installed in the connectingpipe between tank and conservator andresponding to internal arcing faults andslow decomposition of insulating materials.Additionally, backup function of oil alarm.The relay is actuated either by pressurewaves or gas accumulation, or by loss ofoil below the relay level. Seperate contactsare installed for alarm and tripping.In case of a gas accumulation alarm, gassamples can be drawn directly at the relaywith a small chemical testing kit. Discolor-ing of two liquids indicates either arcing byproducts or insulation decomposition prod-ucts in the oil. No change in color indicatesan air bubble.

Dial-type contact thermometer (Fig. 17)

Indicates actual top-oil temperature viacapillary tube. Sensor mounted in well intank cover. Up to four seperately adjust-able alarm contacts and one maximumpointer are available. Installed to be read-able from the ground.With the addition of a CT-fed thermal re-plica circuit, the simulated hot-spot wind-ing temperature of one or more phasescan be indicated on identical thermo-meters. These instruments can also beused to control forced cooling equipment.

Magnetic oil-level indicator (Fig. 18)

The float position inside of the conservatoris transmitted magnetically through thetank wall to the indicator to preserve thetank sealing standard device without con-tacts; devices supplied with limit (position)switches for high- and low-level alarm areavailable. Readable from the ground.

Fig. 18: Magnetic oil-level indicator

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4/12 Siemens Power Engineering Guide · Transmission & Distribution

Accessories and Protective Devices

Protective device (Fig. 19) for hermeti-cally sealed transformers (TUMETIC)

For use on hermetically sealed TUMETICdistribution transformers. Gives alarmupon loss of oil and gas accumulation.Mounted directly at the (permanentlysealed) filler pipe of these transformers.

Pressure relief device (Fig. 20)

Relieves abnormally high internal pressureshock waves. Easily visible operationpointer and alarm contact. Reseals posi-tively after operation and continues tofunction without operator action.

Dehydrating breather (Fig. 21, 22)

A dehydrating breather removes most ofthe moisture from the air which is drawninto the conservator as the transformercools down. The absence of moisture inthe air largely eliminates any reduction inthe breakdown strength of the insulationand prevents any buildup of condensationin the conservator. Therefore, the dehy-drating breather contributes to safe andreliable operation of the transformer.

Bushing current transformer

Up to three ring-type current transformersper phase can be installed in power trans-formers on the upper and lower voltageside. These multiratio CTs are supplied inall common accuracy and burden ratingsfor metering and protection. Their second-ary terminals are brought out to short-circuiting-type terminal blocks in watertightterminal boxes.

Additional accessories

Besides the standard accessories and pro-tective devices there are additional itemsavailable, especially for large power trans-formers. They will be offered and installedon request.Examples are: Fiber-optic temperature measurements Permanent gas-in-oil analysis Permanent water-content measurement Sudden pressure rise relay,etc.

Fig. 20: Pressure relief device with alarm contact andautomatic resetting

Fig. 19: Protective device for hermetically sealedtransformers (TUMETIC)

Fig. 21: Dehydrating breather A DIN 42 567up to 5 MVA

Fig. 22: Dehydrating breather L DIN 42 562over 5 MVA

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4/13Siemens Power Engineering Guide · Transmission & Distribution

8

2W2V2U2N

1W2U1U

Oil drain plugThermometer pocketAdjustment for off-load tap changerRating plate (relocatable)Grounding terminals

23678

Towing eye, 30 mm dia.Lashing lugFiller pipeMounting facility forprotective device

9101112

2

H1

11

9

7

10 3 8

6

B1

12

E E A1

Technical Data Distribution TransformersTUNORMA and TUMETIC

Oil-immersed TUMETICand TUNORMA three-phasedistribution transformers

Standard: DIN 42500 Rated power: 50–2500 kVA Rated frequency: 50 Hz HV rating: up to 36 kV Taps on ± 2.5 % or ± 2 x 2.5 %

HV side: LV rating: 400–720 V

(special designs for upto 12 kV can be built)

Connection: HV winding: deltaLV winding: star(up to 100 kVA: zigzag)

Impedance 4 % (only up to HVvoltage at rated rating 24 kV andcurrent: ≤ 630 kVA) or

6 % (with rated power≥ 630 kVA or withHV rating > 24 kV)

Cooling: ONAN Protection class: IP00 Final coating: RAL 7033 (other

colours are available)

LIAC

Lightning-impulse test voltagePower-frequency test voltage

Um LI AC

1.1

12

24

36

[kV] [kV] [kV]

75

125

170

3

28

50

70

Fig. 23: Insulation level (IP00)The combinations B-A’ (normal losses)and A-C’ (reduced losses) are approxi-mately in line with previous standards.In addition there is the C-C’ combination.Transformers of this kind with additionallyreduced losses are especially economicalwith energy (maximum efficiency > 99%).The higher costs of these transformers arecounteracted by the energy savings whichthey make.Standard HD 428.3.S1 (= DIN 42500-3)specifies the losses for oil distributiontransformers up to Um = 36 kV. For loadlosses the listings D and E, for no-loadlosses the listings D’ and E’ were speci-fied. In order to find the most efficienttransformer, please see part ”Transformerloss evaluation“.

Losses

The standard HD 428.1.S1 (= DIN 42500Part 1) applies to three-phase oil-immerseddistribution transformers 50 Hz, from 50kVA to 2500 kVA, Um to 24 kV.For load losses (Pk), three different listings(A, B and C) were specified. There werealso three listings (A’, B’ and C’) for no-loadlosses (P0) and corresponding sound lev-els.Due to the different requirements, pairsof values were proposed which, in thenational standard, permit one or severalcombinations of losses.DIN 42500 specifies the combinationsA-C’, C-C’ and B-A’ as being most suitable.

2W2V2U2N

1W2U1U

Notes: Tank with strong corrugated walls shown in illustration is the preferred design. With HV ratings up to 24 kVand rated power up to 250 kVA (and with HV ratings > 24-36 kV and rated power up to 800 kVA), the conservator is fittedon the long side just above the LV bushings.

E82

H1

A1

4

E

9

7

10

1

3 8

6

B1

Oil level indicatorOil drain plugThermometer pocketBuchholz relay (optional extra)Dehydrating breather (optional extra)

12345

Adjustment for off-load tap changerRating plate (relocatable)Grounding terminalsTowing eye, 30 mm dia.Lashing lug

6789

10

5

Fig. 24: TUMETIC distribution transformer (sealed tank)

Fig. 25: TUNORMA distribution transformer (with conservator)

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4/14 Siemens Power Engineering Guide · Transmission & Distribution

50

160

(200)

Soundpowerlevel

LWA[dB]

Dist.betweenwheelcenters

E[mm]

Totalweight

LengthA1

WidthB1

HeightH1

[kg] [mm] [mm] [mm]

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

Dimensions

* In case of short-circuits at 75 °C

42

34

34

42

34

33

x

45

35

35

45

35

35

x

47

37

38

47

37

37

x

48

38

38

48

38

38

x

12

24

36

12

24

36

12

24

36

12

24

36

4

4

4

4

4

4

6

4

4

4

4

4

4

6

4

4

4

4

4

4

6

4

4

4

4

4

4

6

..4744-3LB

..4744-3RB

..4744-3TB

..4767-3LB

..4767-3RB

..4767-3TB

..4780-3CB

..5044-3LB

..5044-3RB

..5044-3TB

..5067-3LB

..5067-3RB

..5067-3TB

..5080-3CB

..5244 -3LA

..5244-3RA

..5244-3TA

..5267-3LA

..5267-3RA

..5267-3TA

..5280-3CA

..5344-3LA

..5344-3RA

..5344-3TA

..5367-3LA

..5367-3RA

..5367-3TA

..5380-3CA

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-D´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-D´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-D´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-D´

190

125

125

190

125

125

230

320

210

210

320

210

210

380

460

300

300

460

300

300

520

550

360

360

550

360

360

600

55

47

47

55

47

47

52

59

49

49

59

49

49

56

62

52

52

62

52

52

59

63

53

53

63

53

53

61

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

520

340

400

420

370

430

480

500

500

570

600

520

600

640

660

620

700

760

660

730

800

900

720

840

900

800

890

950

1000

350

430

440

380

460

510

x

500

570

620

530

610

680

x

610

690

780

640

730

820

x

710

830

920

780

910

980

x

860

825

835

760

860

880

1000

1090

980

1030

1020

1030

960

1050

1140

1130

985

1150

1030

1120

1120

1190

1070

1130

1290

1110

1080

1250

980

1045

985

860

860

1100

x

1020

980

930

1140

1030

1060

x

1140

1010

1085

1150

930

1120

x

1190

1120

1130

1290

1230

1180

x

660

660

660

660

660

685

710

660

660

660

685

690

695

780

710

660

660

695

695

710

800

680

660

660

820

755

705

800

1210

1210

1220

1315

1300

1385

1530

1275

1315

1320

1360

1400

1425

1600

1350

1390

1380

1440

1540

1475

1700

1450

1470

1450

1595

1630

1595

1700

1085

1085

1095

1235

1220

1265

x

1110

1145

1150

1245

1280

1305

x

1185

1220

1215

1320

1420

1355

x

1285

1300

1285

1425

1460

1430

x

100

1350

1100

875

1350

1100

875

1450

2150

1750

1475

2150

1750

1475

2350

3100

2350

2000

3100

2350

2000

3350

3600

2760

2350

3600

2760

2350

3800

660

660

660

660

660

660

x

660

660

660

660

660

660

x

710

660

660

660

660

660

x

680

660

680

800

680

690

x

Ratedpower

Sn[kVA]

Max.ratedvolt.HVside

Um[kV]

Impe-dancevoltage

U2[%]

Type Combi-nation oflossesacc.CENELEC

No-loadlosses

P0[W]

Soundpress.level1 mtoler-ance+ 3 dB

LPA[dB]

Loadlosses

Pk 75*[W]4JB… 4HB…

x: on requestDimensions and weights are approximate values. Rated power figures in parentheses are not standardized.

Technical Data Distribution TransformersTUNORMA and TUMETIC

Fig. 26: Selection table: oil-immersed distribution transformers 50 to 2500 kVA

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4/15Siemens Power Engineering Guide · Transmission & Distribution

Soundpowerlevel

LWA[dB]

Dist.betweenwheelcenters

E[mm]

Totalweight

LengthA1

WidthB1

HeightH1

[kg] [mm] [mm] [mm]

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

Dimensions

250

400

(500)

* In case of short-circuits at 75 °C

Ratedpower

Sn[kVA]

Max.ratedvolt.HVside

Um[kV]

Impe-dancevoltage

U2[%]

Type Combi-nation oflossesacc.CENELEC

No-loadlosses

P0[W]

Soundpress.level1 mtoler-ance+ 3 dB

LPA[dB]

Loadlosses

Pk 75*[W]4JB… 4HB…

x: on requestDimensions and weights are approximate values. Rated power figures in parentheses are not standardized.

..5444-3LA

..5444-3RA

..5444-3TA

..5467-3LA

..5467-3RA

..5467-3TA

..5480-3CA

..5544-3LA

..5544-3RA

..5544-3TA

..5567-3LA

..5567-3RA

..5567-3TA

..5580-3CA

..5644-3LA

..5644-3RA

..5644-3TA

..5667-3LA

..5667-3RA

..5667-3TA

..5580-3CA

..5744-3LA

..5744-3RA

..5744-3TA

..5767-3LA

..5767-3RA

..5767-3TA

..5780-3CA

50

40

40

49

39

40

x

50

40

40

50

40

40

x

52

42

42

52

42

42

x

53

42

43

53

42

43

x

12

24

36

12

24

36

12

24

36

12

24

36

4

4

4

4

4

4

6

4

4

4

4

4

4

6

4

4

4

4

4

4

6

4

4

4

4

4

4

6

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

650

425

425

650

425

425

650

780

510

510

780

510

510

760

930

610

610

930

610

610

930

1100

720

720

1100

720

720

1050

65

55

55

65

55

55

62

66

56

56

66

56

56

64

68

58

58

68

58

58

65

69

59

59

69

59

59

66

520

520

520

520

520

520

520

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

830

940

1050

920

1010

1120

1100

980

1120

1240

1050

1170

1250

1220

1180

1320

1470

1240

1370

1490

1480

1410

1650

1700

1460

1650

1860

1680

820

920

1070

900

1010

1140

x

960

1100

1260

1030

1150

1280

x

1160

1310

1470

1220

1350

1520

x

1380

1620

1710

1440

1620

1910

x

1300

1260

1220

1340

1140

1220

1350

1440

1400

1380

1450

1410

1395

1420

1470

1400

1410

1570

1475

1440

1470

1500

1560

1500

1470

1495

1535

1510

1300

1260

1220

1340

1190

1340

x

1330

1250

1260

1350

1270

1290

x

1390

1360

1390

1570

1400

1400

x

1430

1550

1470

1530

1420

1500

x

810

670

690

800

760

715

800

820

820

820

840

820

820

960

930

820

820

940

820

820

990

840

890

820

835

835

820

1030

1450

1480

1530

1620

1675

1640

1680

1655

1690

1665

1655

1755

1675

1700

1700

1700

1695

1655

1760

1765

1830

1710

1745

1745

1755

1815

1860

1900

1285

1415

1310

1450

1510

1475

x

1385

1415

1390

1510

1610

1540

x

1425

1430

1420

1510

1615

1540

x

1440

1470

1470

1610

1665

1645

x

(315)

4200

3250

2750

4200

3250

2750

4250

5000

3850

3250

5000

3850

3250

5400

6000

4600

3850

6000

4600

3850

6200

7100

5450

4550

7100

5450

4550

7800

810

820

700

760

680

710

x

820

820

820

840

820

820

x

930

820

820

940

820

820

x

840

890

820

850

820

820

x

Technical Data Distribution TransformersTUNORMA and TUMETIC

Fig. 27: Selection table: oil-immersed distribution transformers 50 to 2500 kVA

Page 168: 79667665 Siemens Power Engineering Guide Transmission Distribution

4/16 Siemens Power Engineering Guide · Transmission & Distribution

Technical Data Distribution TransformersTUNORMA and TUMETIC

Fig. 28: Selection table: oil-immersed distribution transformers 50 to 2500 kVA

Soundpowerlevel

LWA[dB]

Dist.betweenwheelcenters

E[mm]

Totalweight

LengthA1

WidthB1

HeightH1

[kg] [mm] [mm] [mm]

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

Dimensions

630

1000

* In case of short-circuits at 75 °C

Ratedpower

Sn[kVA]

Max.ratedvolt.HVside

Um[kV]

Impe-dancevoltage

U2[%]

Type Combi-nation oflossesacc.CENELEC

No-loadlosses

P0[W]

Soundpress.level1 mtoler-ance+ 3 dB

LPA[dB]

Loadlosses

Pk 75*[W]4JB… 4HB…

x: on requestDimensions and weights are approximate values. Rated power figures in parentheses are not standardized.

53

43

43

53

43

43

53

43

43

53

43

43

x

55

45

44

55

45

44

x

55

45

45

55

45

45

x

12

24

36

12

24

36

12

24

36

4

4

4

6

6

6

4

4

4

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

..5844-3LA

..5844-3RA

..5844-3TA

..5844-3PA

..5844-3SA

..5844-3UA

..5867-3LA

..5867-3RA

..5867-3TA

..5867-3PA

..5867-3SA

..5867-3UA

..5880-3CA

..5944-3PA

..5944-3SA

..5944-3UA

..5967-3PA

..5967-3SA

..5967-3UA

..45980-

3CA

..6044-3PA

..6044-3SA

..6044-3UA

..6067-3PA

..6067-3SA

..6067-3UA

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

1300

860

860

1200

800

800

1300

860

860

1200

800

800

1300

1450

950

950

1450

950

950

1520

1700

1100

1100

1700

1100

1100

1700

70

60

60

70

60

60

70

60

60

70

60

60

67

72

62

62

72

62

62

68

73

63

63

73

63

63

68

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

820

820

820

820

820

820

820

1660

1850

2000

1750

1950

2160

1690

1940

2100

1730

1970

2240

1950

1990

2210

2520

2000

2390

2590

2400

2450

2660

2800

2530

2750

2830

2850

1660

1810

1990

1760

1920

2130

1650

1920

2130

1720

1960

2210

x

1960

2290

2490

1950

2340

2550

x

2640

2610

2750

2720

2690

2810

x

1680

1495

1535

1720

1665

1670

1665

1685

1600

1780

1645

1740

1740

1780

1720

1760

1720

1760

1770

1800

1790

1830

1830

1830

1790

1725

2120

1480

1420

1380

1560

1600

1560

1640

1680

1490

1580

1640

1670

x

1540

1830

1710

1710

1710

1700

x

1630

1830

1830

1670

1740

1770

x

880

835

820

890

870

830

860

870

820

880

830

880

1080

1000

900

920

1000

960

930

1100

1000

1040

1040

1090

1050

990

1160

1755

1785

1860

1920

1740

1840

1810

1910

1940

1760

1810

1840

1940

1905

1935

1975

1885

1945

1985

2030

2095

2025

2105

2095

2055

2065

2220

1585

1510

1520

1685

1400

1500

1595

1695

1725

1610

1595

1625

x

1660

1630

1730

1670

1730

1780

x

2070

1770

1840

2120

1840

1850

x

(800)

8400

6500

5400

8700

6750

5600

8400

6500

5400

8700

6750

5600

8800

10700

8500

7400

10700

8500

7400

11000

13000

10500

9500

13000

10500

9500

13000

880

820

820

890

870

830

860

870

820

880

830

880

x

1000

960

920

1000

960

930

x

1000

1040

1040

1010

1050

990

x

Page 169: 79667665 Siemens Power Engineering Guide Transmission Distribution

4/17Siemens Power Engineering Guide · Transmission & Distribution

Technical Data Distribution TransformersTUNORMA and TUMETIC

Fig. 29: Selection table: oil-immersed distribution transformers 50 to 2500 kVA

Soundpowerlevel

LWA[dB]

Dist.betweenwheelcenters

E[mm]

Totalweight

LengthA1

WidthB1

HeightH1

[kg] [mm] [mm] [mm]

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

TUM

ETIC

TUN

ORM

A

Dimensions

(1250)

(2000)

2500

* In case of short-circuits at 75 °C

Ratedpower

Sn[kVA]

Max.ratedvolt.HVside

Um[kV]

Impe-dancevoltage

U2[%]

Type Combi-nation oflossesacc.CENELEC

No-loadlosses

P0[W]

Soundpress.level1 mtoler-ance+ 3 dB

LPA[dB]

Loadlosses

Pk 75*[W]4JB… 4HB…

x: on requestDimensions and weights are approximate values. Rated power figures in parentheses are not standardized.

..6144-3PA

..6144-3SA

..6144-3UA

..6167-3PA

..6167-3SA

..6167-3UA

..6180-3CA

..6244-3PA

..6244-3SA

..6244-3UA

..6267-3PA

..6267-3SA

..6267-3UA

..6280-3CA

..6344-3PA

..6344-3SA

..6344-3UA

..6367-3PA

..6367-3SA

..6367-3UA

..63780-

3CA

..6444-3PA

..6444-3SA

..6444-3UA

..6467-3PA

..6467-3SA

..6467-3UA

56

46

46

56

46

46

x

57

47

47

57

47

47

x

58

49

49

58

49

49

x

61

51

51

61

51

51

x

12

24

36

12

24

36

12

24

36

12

24

36

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

B-A'

A-C'

C-C'

B-A'

A-C'

C-C'

E-E´

2100

1300

1300

2100

1300

1300

2150

2600

1700

1700

2600

1700

1700

2600

2900

2050

2050

2900

2050

2050

3200

3500

2500

2500

3500

2500

2500

3800

74

64

64

74

64

64

70

76

66

66

76

66

66

71

78

68

68

78

68

68

75

81

71

71

81

71

71

76

820

820

820

820

820

820

820

820

820

820

820

820

820

820

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

2900

3100

3340

2950

3190

3390

3360

3450

3640

3930

3470

3670

4010

3930

4390

4270

4730

4480

4290

4910

5100

5200

5150

5790

5420

5260

5640

5900

3080

3040

3040

3200

3120

3330

x

3590

3590

3880

3690

3850

3950

x

4450

4430

4710

4500

4490

4840

x

5090

5110

5660

5220

5220

5470

x

1930

1810

1755

2020

1840

1810

2150

1970

2030

2020

2070

2030

2000

2170

2100

2080

2020

2020

2190

2110

2260

2115

2195

2190

2115

2195

2160

2320

1850

1780

1720

1780

1810

1780

x

1870

1760

1900

1830

2000

1850

x

1890

1840

1730

1860

2030

1980

x

2030

1950

2190

2030

2030

2080

x

1260

990

1015

1260

1060

1015

1250

1220

1080

1110

1280

1230

1030

1340

1330

1330

1330

1330

1330

1330

1380

1345

1345

1330

1335

1335

1330

1390

2110

2145

2235

2110

2115

2245

2350

2315

2315

2395

2335

2265

2305

2480

2555

2455

2495

2655

2425

2475

2560

2685

2535

2565

2785

2585

2605

2790

2070

1880

1970

2220

1900

2030

x

2095

2010

2070

2320

2120

2010

x

2540

2250

2170

2660

2280

2180

x

2550

2450

2240

2675

2580

2305

x

1600

16000

13200

11400

16000

13200

11400

16400

20000

17000

14000

20000

17000

14000

19200

25300

21200

17500

25300

21200

17500

22000

29000

26500

22000

29000

26500

22000

29400

1100

990

1000

1100

1060

990

x

1140

1090

1100

1120

1070

1030

x

1330

1330

1330

1330

1330

1330

x

1330

1330

1330

1330

1335

1330

x

Page 170: 79667665 Siemens Power Engineering Guide Transmission Distribution

4/18 Siemens Power Engineering Guide · Transmission & Distribution

Power Transformers – General

Rated power HV range Type oftap changer

Figure/page

[kV]

25 to 123

25 to 123

up to 36

up to 36

72.5 to 145

Fig. 31, page 4/19

Fig. 33, page 4/20

Fig. 35, page 4/21

Fig. 38, page 4/22

Fig. 41, page 4/23

off-load

on-load

off-load

on-load

on-load

[MVA]

3.15 to 10

3.15 to 10

10/16 to 20/31.5

10/16 to 20/31.5

10/16 to 63/100

Note: Off-load tap changers are designed to be operated de-energized only.

Fig. 30: Types of power transformers

Oil-immersed three-phasepower transformers with off-and on-load tap changers

Cooling methods

Transformers up to 10 MVA are designedfor ONAN cooling.By adding fans to these transformers, therating can be increased by 25%.However, in general it is more economicalto select higher ONAN ratings rather thanto add fans.Transformers larger than 10 MVA are de-signed with ONAN/ONAF cooling.Explanation of cooling methods: ONAN: Oil-natural, air-natural cooling ONAF: Oil-natural, air-forced cooling (in

one or two steps)The arrangement with the attached radia-tors, as shown in the illustrations, is thepreferred design. However, other arrange-ments of the cooling equipment are alsopossible.Depending on transportation possibilitiesthe bushings, radiators and expansion tankhave be removed. If necessary, the oil hasto be drained and shipped separately.

Page 171: 79667665 Siemens Power Engineering Guide Transmission Distribution

4/19Siemens Power Engineering Guide · Transmission & Distribution

Power Transformers – Selection TablesTechnical Data, Dimensions and Weights

E

H

EW

L

Oil-immersed three-phasepower transformers withoff-load tap changer3 150–10000 kVA,HV rating: up to 123 kV

Taps onHV side: ± 2 x 2.5 %

Rated frequency: 50 Hz Impedance 6-10 %

voltage: Connection: HV winding: star-

delta connectionalternatively availableup to 24 kVLV winding:star or delta

3150

4000

LV rating No-loadloss

DimensionsL/W/H

Rated power HV rating Load lossat 75 °C

Totalweight

Oilweight

E

5000

6300

8000

10000

[kW]

28

33

35

38

41

46

45

48

53

54

56

62

63

65

72

2800/1850/2870

3200/2170/2940

3100/2300/3630

2550/2510/3020

3150/2490/3730

4560/2200/4540

2550/2840/3200

3200/2690/3080

4780/2600/4540

2580/2770/3530

3250/2850/4000

4880/2630/4590

2670/2900/3720

4060/2750/4170

4970/2900/4810

1600

1900

3100

2300

3300

6300

2500

3700

6600

3300

4200

7300

3900

4700

8600

[mm]

1070

1070

1070

1070

1070

1505

1505

1505

1505

1505

1505

1505

1505

1505

1505

[kVA]ONAN

[kV] [kV] [kW] [kg] [kg] [mm]

6.1–36

7.8–36

50–72.5

9.5–36

50–72.5

90–123

12.2–36

50–72.5

90–123

12.2–36

50–72.5

90–123

15.2–36

50–72.5

90–123

3–24

3–24

3–24

4–24

4–24

5–36

5–24

5–24

5–36

5–24

5–24

5–36

6–24

6–24

5–36

4.6

5.5

6.8

6.5

8.0

9.8

7.7

9.3

11.0

9.4

11.0

12.5

11.0

12.5

14.0

7200

8400

10800

9800

12200

17500

11700

13600

18900

14000

15900

21500

16600

18200

25000

Fig. 32

Fig. 31

Page 172: 79667665 Siemens Power Engineering Guide Transmission Distribution

4/20 Siemens Power Engineering Guide · Transmission & Distribution

Power Transformers – Selection TablesTechnical Data, Dimensions and Weights

Oil-immersed three-phasepower transformerswith on-load tap changer3 150–10 000 kVA,HV rating: up to 123 kV

Taps on ± 16% in ± 8 stepsHV side: of 2%

Rated frequency: 50 Hz Impedance 6–10 %

voltage: Connection: HV winding: star

LV winding:star or delta

Fig. 33

10.9–36

9.2–36

50–72.5

11.5–36

50–72.5

90–123

14.4–36

50–72.5

90–123

18.3–36

50–72.5

90–123

22.9–36

50–72.5

90–123

kW

29

35

37

40

43

49

47

50

56

57

59

65

66

68

76

3400/2300/2900

3500/2700/3000

4150/2350/3600

3600/2400/3200

4200/2700/3700

5300/2700/4650

3700/2700/3300

4300/2900/3850

5600/2900/4650

3850/2500/3500

4600/2800/4050

5650/2950/4650

4400/2600/3650

5200/2850/4100

5750/2950/4700

2300

2600

4100

3100

4500

8000

3600

5000

8500

4500

6000

9000

5200

6500

10250

[mm]

1070

1070

1070

1070

1070

1505

1505

1505

1505

1505

1505

1505

1505

1505

1505

[kVA]ONAN

[kV] [kV] [kW] [kg] [kg] [mm]

3–24

3–24

4–24

4–24

5–24

5–36

5–24

5–24

5–36

5–24

5–24

5–36

6–24

6–24

5–36

4.8

5.8

7.1

6.8

8.4

9.8

8.1

9.8

11.5

9.9

11.5

13.1

11.5

13.1

14.7

9100

10300

13700

12300

15200

21800

14000

17000

23000

17000

19700

25500

20000

22500

29500

3150

4000

5000

6300

8000

10000

Rated power LV rating No-loadloss

HV rating Load lossat 75 °C

DimensionsL/W/H

Totalweight

Oilweight

E

Fig. 34

E

H

EW

L

Page 173: 79667665 Siemens Power Engineering Guide Transmission Distribution

4/21Siemens Power Engineering Guide · Transmission & Distribution

Power Transformers – Selection TablesTechnical Data, Dimensions and Weights

Oil-immersed three-phasepower transformerswith off-load tap changer10/16 to 20/31.5 MVAHV rating: up to 36 kV

Rated frequency: 50 Hz, tapping range± 2 x 2.5%

Connection of starHV winding:

Connection of star or deltaLV winding:

Cooling method: ONAN/ONAF LV range: 6 kV to 36 kV

Fig. 35

Fig. 36

Fig. 37

E

H

EW

LLs

Ws

Hs

[kW]

No-loadloss

12

14

16

19

Load loss atONAN

[kW] [kW]

ONAF

31

37

45

52

80

95

110

130

Impedance voltage ofONAN ONAF

[%] [%]

6.3

6.3

6.4

6.4

10

10

10

10

[MVA]

Rated power atONAN

[MVA]

10

12.5

16

20

16

20

25

31.5

ONAF

L x W x HShippingweightincl. oil

[MVA]

Rated power atONAN

[MVA]

ONAF

10

12.5

16

20

16

20

25

31.5

[kg][mm]

Totalweight

Dimensions

3700

3800

3900

4200

22

25

30

35

[mm] [kg]

2350

2350

2400

2450

3900

4000

4100

4600

[kg]

Oilweight

4200

4500

5000

5700

22000

23000

27000

31500

3600

3700

3800

3900

1550

1600

1600

1650

2650

2800

2800

3000

ShippingdimensionsLs x Ws x Hs

Page 174: 79667665 Siemens Power Engineering Guide Transmission Distribution

4/22 Siemens Power Engineering Guide · Transmission & Distribution

Power Transformers – Selection TablesTechnical Data, Dimensions and Weights

Oil-immersed three-phasepower transformerwith on-load tap changer10/16 to 20/31.5 MVA,HV rating: up to 36 kV

Rated frequency: 50 Hz, tapping range± 16% in ± 9 steps

Connection of starHV winding:

Connection of star or deltaLV winding:

Cooling method: ONAN/ONAF LV range: 6 kV to 36 kV

Fig. 38

Fig. 39

Fig. 40

Ls

H

Ws

WL

Hs

10

12.5

16

20

16

20

25

31.5

12

14

16

19

31

37

45

52

80

95

111

130

6.3

6.3

6.4

6.4

10

10

10

10

[kW]

No-loadloss

Load loss atONAN

[kW] [kW]

ONAFImpedance voltage ofONAN ONAF

[%] [%][MVA]

Rated power atONAN

[MVA]

ONAF

4800

4900

5050

5300

27000

30000

34000

41000

2450

2500

2500

2550

3900

4000

4100

4600

6200

6700

7000

9000

24000

27000

31000

37000

4400

4500

4650

5000

1550

1600

1650

1700

2600

2650

2650

3000

L x W x HShippingweightincl. oil

[MVA]

Rated power atONAN

[MVA]

ONAF

[kg][mm]

Totalweight

Dimensions

[mm] [kg][kg]

Oilweight

ShippingdimensionsLs x Ws x Hs

10

12.5

16

20

16

20

25

31.5

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4/23Siemens Power Engineering Guide · Transmission & Distribution

Power Transformers – Selection TablesTechnical Data, Dimensions and Weights

Oil-immersed three-phasepower transformers withon-load tap changer10/16 to 63/100 MVA,HV rating: from 72.5 to 145 kV

Rated frequency: 50 Hz, tapping range± 16% in ± 9 steps

Connection of starHV winding:

Connection star or deltaof LV winding:

Cooling method: ONAN/ONAF

Fig. 41

Fig. 42

[kW][MVA]

Rated power atONAN

No-loadloss

[MVA]

ONAF

10

12.5

16

20

25

31.5

40

50

63

31.5

13

15

17

20

24

28

35

41

49

Load loss atONAN

[kW] [kW]

ONAF

42

45

51

56

63

71

86

91

113

108

115

125

140

160

180

214

232

285

Impedance voltage ofONAN ONAF

[%] [%]

9.6

9.4

9.6

9.6

9.5

9.5

9.8

10.0

10.5

15.4

15.0

15.0

15.1

15.2

15.0

15.5

16.0

16.7

16

20

25

40

50

63

80

100

L x W x HShippingweightincl. oil

[kg][MVA] [mm]

Rated power atONAN ONAF

Totalweight

Dimensions

10

12.5

16

20

25

31.5

40

50

63

6600

6700

6750

6800

6900

7050

7100

7400

7800

39000

43000

48000

54000

61000

70000

82000

97000

118000

Ls x Ws x Hs

[mm] [kg]

2650

2700

2750

2800

2900

2950

3000

3100

3250

4700

4800

5300

5400

5400

5500

5700

5800

6100

[kg]

Oilweight

12000

12500

13500

14000

14500

17000

18000

20500

25500

35000

39000

43000

49000

56000

65000

75000

90000

109000

5200

5300

5400

5500

5700

5850

6100

6250

6800

1900

1950

2000

2000

2100

2150

2200

2300

2450

3000

3100

3000

3100

3150

3350

3450

3700

4000

Shipping dimensions

31.5

16

20

25

40

50

63

80

100

[MVA]

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4/24 Siemens Power Engineering Guide · Transmission & Distribution

On-load Tap Changers

The on-load tap changers installed inSiemens power transformers are manufac-tured by Maschinenfabrik Reinhausen (MR).MR is a supplier of technically advancedon-load tap changers for oil-immersedpower transformers covering an applicationrange from 100 A to 4,500 A and up to420 kV. About 90,000 MR high-speed re-sistor-type tap changers are succesfully inservice worldwide.The great variety of tap changer models isbased on a modular system which is capa-ble of meeting the individual customers’specifications for the respective operatingconditions of the transformer. Dependingon the required application range selector,switches or diverter switches with tap se-lectors can be used, both available for neu-tral, delta or single-pole connection. Up to107 operating positions can be achieved bythe use of a multiple course tap selector.In addition to the well-known on-load tap-changer for installation in oil-immersedtransformers, MR offers also a standard-ized gas-insulated tap changer for indoorinstallation which will be mounted on dry-type transformers up to approx. 30 MVAand 36 kV, or SF6-type transformers up to40 MVA and 123 kV.The main characteristics of MRproducts are: Compact design Optimum adaption and economic

solutions offered by the great numberof variants

High reliability Long life Reduced maintenance Service friendlinessThe tap changers are mechanicallydriven – via the drive shafts and the bevelgear – by a motor drive attached to thetransformer tank. It is controlled accordingto the step-by-step principle. Electrical andmechanical safety devices prevent over-running of the end positions. Further safe-ty measures, such as the automatic restartfunction, a safety circuit to prevent falsephase sequence and running through posi-tions, ensure the reliable operation of mo-tor drives.

For operation under extremely onerousconditions an oil filter unit is availablefor filtering or filtering and drying of theswitching oil. Voltage monitoring is effect-ed by microprocessor-controlled operationcontrol systems or voltage regulatorswhich include a great variety of data inputand output facilities.In combination with a parallel control unit,several transformers connected in parallelcan be automatically controlled and moni-tored.Furthermore, Maschinenfabrik Reinhausenoffers a worldwide technical service tomaintain their high quality standard.Inspections at regular intervals with onlysmall maintenance requirements guaranteethe reliable operation expected with MRproducts.

Fig. 43: MR motor drive unit MA 7 Fig. 44: Gas-insulated on-load tap changer

Fig. 45: Selection of on-load tap changers from the MR product range

Type VT

Type V Type H Type M Type G

Page 177: 79667665 Siemens Power Engineering Guide Transmission Distribution

4/25Siemens Power Engineering Guide · Transmission & Distribution

Cast-resin Dry-type Transformers, GEAFOL

Standards and regulations

GEAFOL® cast-resin dry-type transformerscomply with IEC recommendationNo. 726, CENELEC HD 464, HD 538and DIN 42 523.

Advantages and applications

GEAFOL distribution and power trans-formers in ratings from 100 to more than20 000 kVA and LI values up to 170 kVare full substitutes for oil-immersed trans-formers with comparable electrical andmechanical data.GEAFOL transformers are designed forindoor installation close to their point ofuse at the center of the major consumers.

They only make use of flame-retardentinorganic insulating materials which freethese transformers from all restrictionsthat apply to oil-filled electrical equipment,such as oil-collecting pits, fire walls, fire-extinguishing equipment, etc.GEAFOL transformers are installed wher-ever oil-filled units cannot be used: insidebuildings, in tunnels, on ships, cranes andoffshore platforms, in ground-water catch-ment areas, in food processing plants, etc.Often they are combined with their prima-ry and secondary switchgear and distribu-tion boards into compact substations thatare installed directly at their point of use.As thyristor-converter transformers forvariable speed drives they can be installedtogether with the converters at the drive

location. This reduces civil works, cablecosts, transmission losses, and installationcosts.GEAFOL transformers are fully LI-rated.They have similar noise levels as compara-ble oil-filled transformers. Taking the aboveindirect cost reductions into account, theyare also frequently cost-competitive.By virtue of their design, GEAFOL trans-formers are completely maintenancefreefor their lifetime.GEAFOL transformers have been insuccessful service since 1965. A lot oflicenses have been granted to majormanufactures throughout the world since.

Fig. 46: GEAFOL cast-resin dry-type transformer

* on-load tap changers on request.

HV windingConsisting of vacuum-potted single foil-type

aluminum coils.See enlarged detail

in Fig. 47

HV terminalsVariable arrangements,for optimal station design.HV tapping links on low-voltage side for adjust-ment to system con-ditions, reconnectablein deenergized state

Resilient spacersTo insulate core and

windings from mechani-cal vibrations, resultingin low noise emissions

LV windingMade of aluminum strip.

Turns firmly gluedtogether by means of

insulating sheet wrappermaterial

Cross-flow fansPermitting a 50% in-crease in the rated power

Temperature monitoringBy PTC thermistor detec-tors in the LV winding

Paint finish onsteel partsMultiple coating,RAL 5009. On request:Two-component varnishor hot-dip galvanizing(for particularly aggressiveenvironments)

Clamping frame and truckRollers can be swung

around for lengthways orsideways travel

Insulation:Mixture of epoxy resin

and quartz powderMakes the transformer

maintenance-free, moist-ure-proof, tropicalized,

flame-resistant and self-extinguishing

LV terminalsNormal arrangement:Top, rearSpecial version: Bottom,available on request atextra charge

Ambient class E2Climatic category C2(If the transformer is in-stalled outdoors, degreeof protection IP 23 mustbe assured)

Three-leg coreMade of grain-oriented,

low-loss electrolami-nations insulated on

both sides

Fire class F1

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4/26 Siemens Power Engineering Guide · Transmission & Distribution

Cast-resin Dry-type Transformers, GEAFOL

1

8

8

223344

5 6

6

7

7U

U

1 2 3 4 5 6 7

2 3 4 5 6 7 8

1

2

3

4

8

7

6

5

2 4 6 8

1 3 5 7

Round-wirewinding

Stripwinding

HV winding

The high-voltage windings are woundfrom aluminum foil, interleaved with high-grade polypropylene insulating foil. Theassembled and connected individual coilsare placed in a heated mold, and are pot-ted in a vaccum furnace with a mixtureof pure silica (quartz sand) and speciallyblended epoxy resins. The only connec-tions to the outside are copper bushings,which are internally bonded to the alumi-num winding connections.The external star or delta connectionsare made of insulated copper connectorsto guarantee an optimal installation design.The resulting high-voltage windings arefire-resistant, moistureproof, corrosion-proof, and show excellent aging propertiesunder all indoor operating conditions.(For outdoor use, specially designed sheet-metal enclosures are available).The foil windings combine a simple wind-ing technique with a high degree of elec-trical safety. The insulation is subjectedto less electrical stress than in othertypes of windings. In a conven-tional round-wire winding,the interturn voltagecan add up to twice theinterlayer voltage, whilein a foil winding it never exeeds the simplevoltage per turn because a layer consistsof only one winding turn. Result: a highAC voltage and impulse-voltage withstandcapacity.Why aluminum? The thermal expansioncoefficients of aluminum and cast resin areso similar that thermal stresses resultingfrom load changes are kept to a minimum(see Fig. 47).

LV winding

The standard low-voltage winding with itsconsiderably reduced dielectric stresses iswound from single aluminum sheets withinterleaved cast-resin impregnated fiber-glass fabric.The assembled coils are then oven-curedto form uniformly bonded solid cylindersthat are impervious to moisture. Throughthe single-sheet winding design, excellentdynamic stability under short-circuit con-ditions is achieved. Connections are sub-merged-arc-welded to the aluminumsheets and are extended either as alu-minum or copper busbars to the secondaryterminals.

Fig. 47: High-voltage encapsulated winding design of GEAFOL cast-resin transformer and voltage stress of aconventional round-wire winding (above) and the foil winding (below)

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4/27Siemens Power Engineering Guide · Transmission & Distribution

Cast-resin Dry-type Transformers, GEAFOL

Fire safety

GEAFOL transformers use only flame-retardent and self-extinguishing materialsin their construction. No additional sub-stances, such as aluminum oxide trihy-drate, which could negatively influencethe mechanical stability of the cast-resinmolding material, is used. Internal arcingfrom electrical faults and externally appliedflames do not cause the transformers toburst or burn. After the source of ignitionis removed, the transformer is self-extin-guishing. This design has been approvedby fire officials in many countries for instal-lation in populated buildings and otherstructures.The environmental safety of the combus-tion residues has been proven in manytests.

Categorization of cast-resintransformers

Dry-type transformers have to be cate-gorized under the sections listed below: Environmental category Climatic category Fire categoryThese categories have to be shown on therating plate of each dry-type transformer.

The properties laid down in the standardsfor ratings within the approximate categoryrelating to environment (humidity), climateand fire behavior have to be demonstratedby means of tests.These tests are described for the environ-mental category (code number E0, E1 andE2) and for the climatic category (codenumber C1, C2) in DIN VDE 0532 Part 6(corresponding to HD 464). According tothis standard, they are to be carried out oncomplete transformers.The tests of fire behavior (fire categorycode numbers F0 and F1) are limited totests on a duplication of a complete trans-former. It consists of a core leg, a low-volt-age winding and a high-voltage winding.The specifications for fire category F2 aredetermined by agreement between themanufacturer and the customer.Siemens have carried out a lot of tests.The results for our GEAFOL transformersare something to be proud of: Environmental category E2 Climatic category C2 Fire category F1This good behavior is solely due to theGEAFOL cast-resin mix which has beenused successfully for decades.

Insulation class and temperature rise

The high-voltage winding and the low-voltage winding utilize class F insulatingmaterials with a mean temperature riseof 100 K (standard design).

Overload capability

GEAFOL transformers can be overloadedpermanently up to 50% (with a corre-sponding increase in impedance voltage)if additional radial cooling fans are installed.(Dimensions increase by approximately200 mm in length and width.) Short-timeoverloads are uncritical as long as themaximum winding temperatures are notexceeded for extended periods of time.

Temperature monitoring

Each GEAFOL transformer is fitted withthree temperature sensors installed inthe LV winding, and a solid-state trippingdevice with relay output. The PTC thermis-tors used for sensing are selected for theapplicable maximum hot-spot winding tem-perature. Additional sets of sensors withlower temperature points can be installedfor them and for fan control purposes. Ad-ditional dial-type thermometers and Pt100are available, too. For operating voltagesof the LV winding of 3.6 kV and higher,special temperature measuring equipmentcan be provided.Auxiliary wiring is run in protective conduitand terminated in a central LV terminalbox (optional). Each wire and terminal isidentified, and a wiring diagram is perma-nently attached to the inside cover of thisterminal box.

Installation and enclosures

Indoor installation in electrical operatingrooms or in various sheet-metal enclosuresis the preferred method of installation.The transformers need only be protectedagainst access to the terminals or thewinding surfaces, against direct sunlight,and against water. Sufficient ventilationmust be provided by the installation loca-tion or the enclosure. Otherwise forced-aircooling must be specified or provided byothers.

Fig. 48: Flammability test of cast-resin transformer

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4/28 Siemens Power Engineering Guide · Transmission & Distribution

Cast-resin Dry-type Transformers, GEAFOL

Instead of the standard open terminals,insulated plug-type elbow connectors canbe supplied for the high-voltage side withLI ratings up to 170 kV. Primary cables areusually fed to the transformer from trench-es below, but can also be connected fromabove.Secondary connections can be made bymultiple insulated cables, or by busbars,from either below or above. Secondaryterminals are either aluminum or copperbusbar stubs, drilled to specification.A variety of indoor and outdoor enclosuresin different protection classes are availablefor the transformers alone, or for indoorcompact substations in conjunction withhigh- and low-voltage switchgear cubicles.

Recycling of GEAFOL transformers

Of all the GEAFOL transformers manufac-tured since 1965, even the oldest units arenot about to reach the end of their servicelife expectancy. In spite of this, a lot ofexperiences have been made over theyears with the recycling of coils that havebecome unusable due to faulty manufac-ture or damage. These experiences showthat all the metallic components, i.e. ap-prox. 90% of all materials, can be fully re-covered economically. The recycling meth-od used by Siemens does not pollute theenvironment. In view of the value of thesecondary raw materials, the procedurecan be economical even considering thecurrently small amounts.

Fig. 50: Radial cooling fans on GEAFOL transformer for AF cooling

Fig. 49: GEAFOL transformer with plug-type cable connections

Fig. 51: GEAFOL transformer in protective housing to IP 20/40

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4/29Siemens Power Engineering Guide · Transmission & Distribution

GEAFOL Cast-resin Selection Tables,Technical Data, Dimensions and Weights

Um LJ AC

1.1

12

24

36

[kV] [kV] [kV]

75

95**

145**

3

28

50

70

E

H1

2U 2V 2W

A1EB1

2N

Standard: DIN 42523 Rated power: 100–20000 kVA* Rated frequency: 50 Hz HV rating: up to 36 kV LV rating: up to 780 V;

special designsfor up to 12 kV arepossible

Tappings on ± 2.5% or ± 2 x 2.5%HV side:

Connection: HV winding: deltaLV winding: star

Impedance 4–8%voltage at ratedcurrent:

Insulation class: HV/LV = F/F Temperature HV/LV = 100/100 K

rise: Color of metal RAL 5009 (other

parts: colors are available)

Fig. 53: GEAFOL cast-resin transformer

Soundpowerlevel

LWA[dB]

Distancebetweenwheelcenters

E[mm]

Totalweight

Length Width Height

GGES[kg]

A1[mm]

B1[mm]

H1[mm]

Dimensions

* In case of short-circuits at 75 °C** In case of short-circuits at 120 °C

45

37

45

37

45

37

45

37

47

39

47

39

47

39

47

39

12

24

12

24

4

4

6

6

4

4

6

6

4

4

6

6

4

4

6

6

.5044-3CA

.5044-3GA

.5044-3DA

.5044-3HA

.5064-3CA

.5064-3GA

.5064-3DA

.5064-3HA

.5244-3CA

.5244-3GA

.5244-3DA

.5244-3HA

.5264-3CA

.5264-3GA

.5264-3DA

.5264-3HA

440

320

360

300

600

400

420

330

610

440

500

400

800

580

600

480

59

51

59

51

59

51

59

51

62

54

62

54

62

54

62

54

without wheels

without wheels

without wheels

without wheels

without wheels

without wheels

without wheels

without wheels

520

520

520

520

520

520

520

520

630

760

590

660

750

830

660

770

770

920

750

850

910

940

820

900

1210

1230

1190

1230

1310

1300

1250

1300

1220

1290

1270

1300

1330

1310

1310

1350

705

710

705

710

755

755

750

755

710

720

720

725

725

720

725

765

835

890

860

855

935

940

915

930

1040

1050

990

985

1090

1095

1075

1060

1600

1600

2000

2000

1500

1500

1800

1800

2300

2300

2300

2300

2200

2200

2500

2500

Ratedpower

Sn[kVA]

Ratedvoltage

Um[kV]

Impe-dancevoltage

U2[%]

Type No-loadlosses

P0[W]

LPA[dB]

Loadlosses

Pk 75*[W]4GB…

Rated power figures in parentheses are not standardized.

1900

1900

2300

2300

1750

1750

2050

2050

2600

2600

2700

2700

2500

2500

2900

2900

Loadlosses

Pk 120**[W]

100

160

Dimensions and weights are approximate values and valid for 400 V on the secondary side, vector-group can be Dyn 5 or Dyn 11.

Soundpress.level1 mtoler-ance+ 3 dB

Fig. 52: Insulation level

* power rating > 2.5 MVA uopn request** other levels upon request

Fig. 54: GEAFOL cast-resin transformers 50 to 2500 kVA

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4/30 Siemens Power Engineering Guide · Transmission & Distribution

GEAFOL Cast-resin Selection Tables,Technical Data, Dimensions and Weights

Fig. 55: GEAFOL cast-resin transformers 50 to 2500 kVA

(315)

Soundpowerlevel

LWA[dB]

Distancebetweenwheelcenters

E[mm]

Totalweight

Length Width Height

GGES[kg]

A1[mm]

B1[mm]

H1[mm]

Dimensions

* In case of short-circuits at 75 °C** In case of short-circuits at 120 °C

50

42

50

42

50

41

50

41

50

52

43

51

43

51

43

51

43

51

52

44

52

44

52

44

52

44

52

53

45

53

45

53

44

53

45

53

12

24

36

12

24

36

12

24

36

12

24

36

4

4

6

6

4

4

6

6

6

4

4

6

6

4

4

6

6

6

4

4

6

6

4

4

6

6

6

4

4

6

6

4

4

6

6

6

.5444-3CA

.5444-3GA

.5444-3DA

.5444-3HA

.5464-3CA

.5464-3GA

.5464-3DA

.5464-3HA

.5475-3CA

.5544-3CA

.5544-3GA

.5544-3DA

.5544-3HA

.5564-3CA

.5564-3GA

.5564-3DA

.5564-3HA

.5575-3CA

.5644-3CA

.5644-3GA

.5644-3DA

.5644-3HA

.5664-3CA

.5664-3GA

.5664-3DA

.5664-3HA

.5675-3CA

.5744-3CA

.5744-3GA

.5744-3DA

.5744-3HA

.5764-3CA

.5764-3GA

.5764-3DA

.5764-3HA

.5775-3CA

820

600

700

570

1050

800

880

650

1300

980

720

850

680

1250

930

1000

780

1450

1150

880

1000

820

1450

1100

1200

940

1700

1350

1000

1200

980

1700

1270

1400

1100

1900

65

57

65

57

65

57

65

57

65

67

59

67

59

67

59

67

59

67

68

60

68

60

68

60

68

60

68

69

61

69

61

69

61

69

61

69

520

520

520

520

520

520

520

520

520

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

1040

1170

990

1120

1190

1230

990

1180

1700

1160

1320

1150

1290

1250

1400

1190

1300

1900

1310

1430

1250

1350

1410

1570

1350

1460

2100

1520

1740

1470

1620

1620

1830

1580

1720

2600

1330

1330

1350

1390

1390

1400

1360

1430

1900

1370

1380

1380

1410

1410

1440

1410

1460

1950

1380

1380

1410

1430

1440

1460

1480

1480

2000

1410

1450

1460

1490

1500

1540

1540

1560

2050

730

730

740

745

735

735

735

745

900

820

820

830

830

820

825

825

830

920

820

820

825

830

825

830

835

835

920

830

835

845

845

835

840

850

850

940

1110

1135

1065

1090

1120

1150

1140

1160

1350

1125

1195

1140

1165

1195

1205

1185

1195

1400

1265

1290

1195

1195

1280

1280

1275

1280

1440

1320

1345

1275

1290

1330

1350

1305

1320

1500

250 3000

3000

2900

2900

2900

2900

3100

3100

3800

3300

3300

3400

3400

3400

3400

3600

3600

4500

4300

4300

4300

4300

3900

3900

4100

4100

5100

4900

4900

5600

5600

4800

4800

5000

5000

6000

Ratedpower

Sn[kVA]

Ratedvoltage

Um[kV]

Impe-dancevoltage

U2[%]

Type No-loadlosses

P0[W]

LPA[dB]

Loadlosses

Pk 75*[W]4GB…

Rated power figures in parentheses are not standardized.

3500

3400

3300

3300

3300

3300

3600

3600

4370

3800

3800

3900

3900

3900

3900

4100

4100

5170

4900

4900

4900

4900

4500

4500

4700

4700

5860

5600

5600

6400

6400

5500

5500

5700

5700

6900

Loadlosses

Pk 120**[W]

Dimensions and weights are approximate values and valid for 400 V on the secondary side, vector-group can be Dyn 5 or Dyn 11.

Soundpress.level1 mtoler-ance+ 3 dB

400

(500)

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4/31Siemens Power Engineering Guide · Transmission & Distribution

GEAFOL Cast-resin Selection Tables,Technical Data, Dimensions and Weights

Soundpowerlevel

LWA[dB]

Distancebetweenwheelcenters

E[mm]

Totalweight

Length Width Height

GGES[kg]

A1[mm]

B1[mm]

H1[mm]

Dimensions

(800)

* In case of short-circuits at 75 °C** In case of short-circuits at 120 °C

54

45

54

45

53

45

53

45

53

55

47

55

47

55

47

55

47

55

55

47

56

47

55

47

55

47

55

57

49

57

49

57

12

24

36

12

24

36

12

24

36

12

24

36

4

4

6

6

4

4

6

6

6

4

4

6

6

4

4

6

6

6

4

4

6

6

4

4

6

6

6

6

6

6

6

6

.5844-3CA

.5844-3GA

.5844-3DA

.5844-3HA

.5864-3CA

.5864-3GA

.5864-3DA

.5864-3HA

.5875-3CA

.5944-3CA

.5944-3GA

.5944-3DA

.5944-3HA

.5964-3CA

.5964-3GA

.5964-3DA

.5964-3HA

.5975-3CA

.6044-3CA

.6044-3GA

.6044-3DA

.6044-3HA

.6064-3CA

..6064-3GA

.6064-3DA

.6064-3HA

.6075-3CA

.6144-3DA

.6144-3HA

.6164-3DA

.6164-3HA

.6175-3CA

1500

1150

1370

1150

1950

1500

1650

1250

2200

1850

1450

1700

1350

2100

1600

1900

1450

2600

2200

1650

2000

1500

2400

1850

2300

1750

3000

2400

1850

2700

2100

3500

70

62

70

62

70

62

70

62

70

72

64

72

64

72

64

71

64

72

73

65

73

65

73

65

73

65

73

75

67

75

67

75

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

670

820

820

820

820

820

820

820

820

820

820

820

820

820

520

1830

2070

1770

1990

1860

2100

1810

2050

2900

2080

2430

2060

2330

2150

2550

2110

2390

3300

2480

2850

2420

2750

2570

3060

2510

2910

3900

2900

3370

3020

3490

4500

1510

1470

1550

1590

1550

1600

1580

1620

2070

1570

1590

1560

1600

1610

1650

1610

1630

2140

1590

1620

1620

1660

1660

1680

1680

1730

2200

1780

1790

1820

1850

2300

840

835

860

865

845

850

855

860

940

850

855

865

870

845

855

860

865

950

990

990

990

990

990

990

990

990

1050

990

990

990

990

1060

1345

1505

1295

1310

1380

1400

1345

1370

1650

1560

1640

1490

1530

1580

1620

1590

1595

1850

1775

1795

1560

1560

1730

1815

1620

1645

1900

1605

1705

1635

1675

2000

630 6400

6400

6400

6400

6000

6000

6400

6400

7000

7800

7800

7600

7600

7500

7500

7900

7900

8200

8900

8900

8500

8500

8700

8700

9200

9600

9500

9600

10500

10000

10500

11000

7300

7300

7400

7400

6900

6900

7300

7300

8000

9000

9000

8700

8700

8600

8600

9100

9100

9400

10200

10200

9700

9700

10000

10000

10500

11000

10900

11000

12000

11500

12000

12600

Ratedpower

Sn[kVA]

Ratedvoltage

Um[kV]

Impe-dancevoltage

U2[%]

Type No-loadlosses

P0[W]

LPA[dB]

Loadlosses

Pk 75*[W]4GB…

Rated power figures in parentheses are not standardized.

Loadlosses

Pk 120**[W]

Dimensions and weights are approximate values and valid for 400 V on the secondary side, vector-group can be Dyn 5 or Dyn 11.

Soundpress.level1 mtoler-ance+ 3 dB

(1250)

1000

Fig. 56: GEAFOL cast-resin transformers 50 to 2500 kVA

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4/32 Siemens Power Engineering Guide · Transmission & Distribution

GEAFOL Cast-resin Selection Tables,Technical Data, Dimensions and Weights

Soundpowerlevel

LWA[dB]

Distancebetweenwheelcenters

E[mm]

Totalweight

Length Width Height

GGES[kg]

A1[mm]

B1[mm]

H1[mm]

Dimensions

(2000)

2500

* In case of short-circuits at 75 °C** In case of short-circuits at 120 °CRated power >2500 kVA to 20 MVA on request.

58

50

58

49

58

59

51

59

51

59

62

51

61

51

61

12

24

36

12

24

36

12

24

36

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

.6244-3DA

.6244-3HA

.6264-3DA

.6264-3HA

.6275-3CA

.6344-3DA

.6344-3HA

.6364-3DA

.6364-3HA

.6375-3CA

.6444-3DA

.6444-3HA

.6464-3DA

.6464-3HA

.6475-3CA

2800

2100

3100

2400

4300

3600

2650

4000

3000

5100

4300

3000

5000

3600

6400

76

68

76

68

76

78

70

78

70

78

81

71

81

71

81

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

1070

3550

4170

3640

4080

5600

4380

5140

4410

4920

6300

5130

6230

5280

6220

7900

1840

1880

1880

1900

2500

1950

1990

2020

2040

2500

2110

2170

2170

2220

2700

995

1005

995

1005

1100

1280

1280

1280

1280

1280

1280

1280

1280

1280

1280

2025

2065

2035

2035

2400

2150

2205

2160

2180

2400

2150

2205

2160

2180

2400

1600 11000

11400

11800

12300

12700

14000

14500

14500

14900

15400

17600

18400

17600

18000

18700

12500

13000

13500

14000

14600

16000

16500

16500

17000

17700

20000

21000

20000

20500

21500

Ratedpower

Sn[kVA]

Ratedvoltage

Um[kV]

Impe-dancevoltage

U2[%]

Type No-loadlosses

P0[W]

LPA[dB]

Loadlosses

Pk 75*[W]4GB…

Rated power figures in parentheses are not standardized.

Loadlosses

Pk 120**[W]

Dimensions and weights are approximate values and valid for 400 V on the secondary side, vector-group can be Dyn 5 or Dyn 11.

Soundpress.level1 mtoler-ance+ 3 dB

Fig. 57: GEAFOL cast-resin transformers 50 to 2500 kVA

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4/33Siemens Power Engineering Guide · Transmission & Distribution

Special Transformers and Reactors

Rectifier transformer for electrostaticprecipitators

DC voltages up to 148 kV are used toremove solid pollutants from smokestackemissions in industrial and power generat-ing plants. Siemens has developed specialtransformers with built-in silicon rectifierdiodes, so-called rectiformers, for thispurpose.These units are constructed based on theTUMETIC hermetically sealed transformerprinciple. In addition to the transformerwindings, the following components arecontained in this variable-volume sealedoil tank: LV current-attenuating reactor HV rectifier bridge HV measuring resistor HF reactorThe DC voltage is fed through the tanktop by means of a single bushing. Theseparate LV terminal 60x, mounted on thetransformer side, contains the LV terminal,HV flashover detection with amplifierfor kV measurement, shunt for precipitatorcurrent measurement, 2 surge-voltageprotectors.To adjust the DC output voltage, the LVwindings of the transformer are suppliedvia a thyristor AC power controller.This controller is mounted inside a sepa-rate weatherproof control cabinet.For technical data please inquire.

Flameproof transformers for coal mines

In deep-shaft coal mines the release ofmethane must be taken into account inthe design of electrical systems. Siemenshas developed flameproof distributiontransformers that comply with the relevantGerman mine safety codes, which apply invarious other countries as well.The flameproof units are dry-type three-phase distribution transformers inside cor-rugated steel enclosures with integral high-and low-voltage terminal boxes. The enclo-sures are designed to withstand internalexplosions of combustible gas withoutigniting the surrounding explosive atmos-phere.The transformers are supplied for primaryvoltages of up to 10 kV, secondary volt-ages of 525 and 1050 V at 50/60 Hz, andpower ratings up to 1000 kVA.

Fig. 59: Flameproof distribution transformer 630 kVA for coal mines

Fig. 58: Rectifier-transformer for electrostatic precipitator

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4/34 Siemens Power Engineering Guide · Transmission & Distribution

Special Transformers and Reactors

Transformers for thyristor converters

These are special oil-immersed or cast-resin power transformers that are de-signed for the special demands of thyristorconverter or diode rectifier operation.The effects of such conversion equipmenton transformers and additional construc-tion requirements are as follows: Increased load by harmonic currents Continuous short-circuit-like stresses

by current communication and commu-nication faults

Balancing of phase currents in multiplewinding systems(e.g. 12-pulse systems)

Overload factor up to 2.5 Types for 12-pulse systems, if required.Siemens supplies oil-filled converter trans-formers of all ratings and configurationsknown today, and dry-type cast-resinconverter transformers up to more than20 MVA and 200 kV LI.To define and quote for such transformers,it is necessary to know considerable de-tails on the converter to be supplied andon the line feeding it. These transformersare almost exclusively inquired togetherwith the respective drive or rectifier sys-tem and are always custom-engineered forthe given application.

Arc-suppression coils fordistribution networks

(Neutral reactors or Petersen coils)Arc-suppression coils or Petersen coilsare used in distribution networks up to150 kV to neutralize the prospective capa-citive ground-fault current by inserting acorresponding reactance into the starpoint-to-ground connection of the network.Through this method, damages due toarcing ground faults can be limited oravoided entirely. System operation canoften be maintained under ground-faultconditions until corrective switching ac-tions have been taken; temporary groundfaults require no action at all.Since the prospective capacitive ground-fault current depends on the varying sys-tem condition, the neutralizing reactormust be adjustable – either in steps, orcontinuously.Siemens builds Petersen coils with fixedand variable reactance in sizes from 50 kVAto 30 MVA, and line-to-neutral voltages of5 to 150 kV. Adjustment in steps is realizedwith off-load tapping switches, resulting inan adjustment ratio of about 1:2.5. Contin-uous adjustment results in tuning ratiosof better than 1:10 and is done via electricmotor or electrohydraulically operatedmoving-core mechanisms.Current transformers for measuring andrecording purposes, as well as ground-faultlocating devices are optionally available.

Fig. 61: Arc-suppression coil with electrically controlled reactance adjustmentFig. 60: Dry-type converter transformer GEAFOL for rolling mill

Neutral grounding transformers

When a neutral grounding reactor orground-fault neutralizer is required in athree-phase system and no suitable neutralis available, a neutral must be providedby using a neutral grounding transformer.Neutral grounding transformers are avail-able for continuous operation or short-timeoperation.The zero impedance is normally low.The standard vector groups are zigzag orwye/delta. Some other vector groups arealso possible.Neutral grounding transformers can bebuilt by Siemens in all common powerratings.Normally, the neutral grounding transform-ers are built in oil-immersed design, how-ever, they can also be built in cast-resindesign.

For further information please contact:

Distribution transformers:Fax: ++ 49-7021- 5085 48Power transformers:Fax: ++ 49 -911-4 342147

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Power Cables

Contents Page

Power Cables – General 5/2–5/6

Medium- and Low-Voltage Cablesup to 45 kV 5/7–5/12

Accessories for Low-and Medium-Voltage Cables 5/13–5/20

High-Voltage Cablesup to 290/500 kV 5/21–5/22

Accessories for High-Voltage Cablesup to 290/500 kV 5/23–5/24

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5/2 Siemens Power Engineering Guide · Transmission & Distribution

Power Cables – General

Application

Cables intended for the transmission anddistribution of electrical energy are mainlyused in power plants, in distribution sys-tems and substations of power supply utili-ties, and in industry.They are preferably used where overheadlines are not suitable, e.g. in densely built-up areas, in cities (pedestrian zones), in-dustrial installations and buildings.For power supply cables there are twomain fields of application with differentstresses (Fig. 1):

Stresses and requirements

These cables, especially the insulation(electrical strength) of buried cables, mustbe reliable and have a long service life. Inorder to fulfil this requirement for Siemenscables, the cable construction as well asthe materials and manufacturing processesare permanently improved with a lot of de-velopment work.The different stresses determined by thefunction form the basis for the definition ofthe cable requirements (Fig. 2).

In view of the possible external stressesfor power cables, cables are be dividedinto two standard cable types, i. e. one forlaying in the ground (distribution cables)and one for installation in air (installationcables) (Fig. 3).High-voltage cables are often designedaccording to the specific stresses of eachspecial case of application.The Siemens instructions AR 320-220 andAR 320-1-220 contain detailed informationon the application of cables, e. g. permis-sible pulling forces, limit temperatures,bending radii, cable fixing, storage andtransport, etc.

Voltages

Rated voltage– Power cables are classified according

to the rated voltages U0 /U and Um.– U0 is the rms value between con-

ductor and ground or groundedmetallic covering (concentric conduc-tor, screen, armor, metal sheath).

– U is the rms value between phaseconductors.

– Um is the maximum rms valuebetween phase conductors.

In an a. c. system, the rated voltageUm must be at least equal to the highestvoltage of the system Ub max for whichit is intended.

U0 = U/ 3– For application in three-phase and

single-phase systems the main stan-dard rated voltages (rounded values)in compliance with IEC 183 are givenin Fig. 4.

The maximum continuous operating-volt-age at normal operation for low voltagecables with rated voltage of 0.6/1kV(Um = 1.2 kV) is

– 1.8 kV in d.c. systems– 3.6 kV in a.c. systems

for PVC-insulated cables having aconcentric conductor or armor andconductor cross-sectional areas from240 mm2 and above.

Directlyin theground

Laying in the ground

Outdoors

Installation in air

In ducts

In concrete

In water

Indoors

In channels

Fig. 1: Fields of application

Stresses determined by the function:

Current

Voltage

Thermalstress

Electricalstress

Thermal/mechanicalstress

Thermalstress

Electricalstress

Normaloperation

Short-circuit

Ground fault

Transientwaves

Operationunderfault con-ditions

Fig. 2: Stresses determined by the function

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5/3Siemens Power Engineering Guide · Transmission & Distribution

Mechanical

Chemicals(permanent influence),oil, acids

Moisture (water)Temperature

Fire propagation

Chemical

Climatic

Fire behavior

Tensile strength (laying)Impact strength (civil works)AbrasionTermites, rodents, etc.

Chemicals(short-term influence)Ozone

Moisture (rain, humidity)UV radiationTemperature (cold, heat)

Fire propagationCorrosive combustion gasesSmoke densityCircuit integrity of cable installation

Tensile strength (laying)Pressure force (cleats)Vibrations

Laying in the ground Installation in air

Power Cables – General

Fig. 3: Stresses determined by the installation method

Fig. 4

Current ratings

For safe project planning of cable installa-tions, the cross-sectional area of conductorshall be determined such that the require-mentcurrent-carrying capacity Iz ≥ loading Ib

is fulfilled for all operating conditions whichcan occur. A distinction is made betweenthe current-carrying capacity for normal operation and for short-circuit

(operation under fault conditions)Especially in low-voltage systems, thecross-sectional area of the conductor mustbe additionally determined in respect ofthe permitted voltage drop ∆U. In order toavoid thermal overloading of the cable asuitable protective device also has to beselected. Besides that, the relevant instal-lation rules shall be observed.With regard to these criteria, brief in-structions for project planning are givenin Part 2 of the book “Power Cables andtheir Application”. They are sufficient formost cases when using the values listedin this book. The procedure is shown byexamples.More comprehensive calculation meth-ods with detailed project planning data canbe taken from Part 1 of the book “PowerCables and their Application”.Order-Nr.: Part 1: A19100-L531-F159-X-7600Part 2: A19100-L531-F506-X-7600.For high-voltage cables, the current-carry-ing capacity is to be examined for eachspecial case of application. It depends ona lot of special laying and installation con-ditions so that it is not possible to givestandard values.

Standards

To ensure the operational properties andthe high quality of all types of Siemenscables, short-term and long-term tests arecarried out. They are based on nationaland international standards such as VDEand IEC. A perfect quality system accord-ing to ISO 9001 ensures a maximum ofreliability of Siemens cables.

0.6

3.6

6

12

18

64

76

87

127

160

290

1.2

7.2

12

24

36

123

145

170

245

300

525

1.4

8.3

14

28

42

142

168

196

284

346

606

0.7

4.1

7

14

21

71

84

98

142

173

303

Uo Um in three-phasesystems

Um in single-phase a.c. systems

Both phaseconductorsinsulated

One phaseconductorgrounded

[kV] [kV][kV] [kV]

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5/4 Siemens Power Engineering Guide · Transmission & Distribution

To protect the insulation of PROTODUR orPROTOTHEN X cables against permanent,intensive ingress of fuels, oils or solvents,a lead sheath can be provided under thePVC sheath.For high-voltage cables a lead sheath isnormally used for low-pressure oil-filledcables, but it is also available for cableswith XLPE insulation. For these high-volt-age PROTOTHEN X cables, however,normally a screen of round copper wireswith a cross-sectional area of 35 mm2 or50 mm2 is used together with an alumi-num laminated PE sheath.For all types of insulation used for high-voltage cables, a metal sheath of alumi-num is available as well. The advantageof such a cable design with a corrugatedaluminum sheath is the very high mechani-cal protection and, under fault conditions,the very high ground-fault current-carryingcapacity.

Outer coverings

For low-voltage PROTODUR cables withPVC insulation and PROTOTHEN X cableswith XLPE insulation, a PVC sheath is nor-mally applied.Medium-voltage XLPE-insulated cables nor-mally have a sheath of polyethylene whichis more resistant with respect to the me-chanical properties. PVC sheaths can alsobe provided, especially for undergroundmining or indoor installation (flame retar-dance according to IEC 332-2).As already mentioned, high-voltage cableshaving a screen of round copper wiresare provided with an aluminum laminatedPE sheath consisting of an aluminum tapecoated with PE copolymer on the outer

Power Cables – General

Constructional elementsof cables

Conductors

The conductors comply with IEC 228.The type and construction of conductor –whether circular solid (RE) or circularstranded (RM), sector-shaped solid (SE)or sector-shaped stranded (SM) – can betaken from the relevant tables in the book“Power Cables and their Application”,Part 2. The smallest permissible nominalcross-sectional areas for circular and sec-tor-shaped conductors are specified in therelevant standard.Especially for high-voltage low-pressureoil-filled cables, circular stranded hollowconductors (RM...H) are used. For cross-sectional areas of 1000 mm2 and above,special segmental conductors, also knownas Milliken conductors, are used in orderto reduce current losses occurring due toskin and proximity effects.

Insulation

In the field of cables with extruded insula-tion, there are two dominating insulationmaterials which have proved to be reliable.One of these two materials is XLPE whichis used for Siemens PROTOTHEN X ca-bles. These cables have a high-grade insu-lating compound of high-molecular purepolyethylene with a cross-linked structurewhich is distinguished by excellent proper-ties. Cables up to 500 kV are designedwith this insulation material because ofthe very low and almost constant dielectricloss factor at all operating temperatures.The permittivity is also relatively low andunaffected by fluctuations in temperatureso that total dielectric losses of SiemensPROTOTHEN X cables are extremely low.The conductor screen and insulationscreen of these cables are extruded to-gether with the insulation (triple extrusion)in special manufacturing processes. So theinsulation screen is generally solidly bond-ed to the insulation. To remove this insula-tion screen during installation of accesso-ries, a special peeling tool is required.Designs with easy-strip semiconductivelayers are also available for medium-volt-age cables.The second dominating material for ex-truded insulations is PVC, but it is mainlyused for cables designed for voltages from1 kV up to and including 6 kV. SiemensPROTODUR cables have an insulationbased on that material. Compared to XLPE,these cables have a significantly higherpermittivity.

Oil-impregnated paper, a classic insulationmaterial, is still used especially for extra-high-voltage low-pressure oil-filled cables.Two advantages of this type of insulationare the vast experience that stands be-hind it and the high degree of reliability soimpressively demonstrated by the fault-free service of these cables decade afterdecade.

Identification of cores forlow-voltage cables

Cables with more than 5 cores (controlcables) have black cores with white im-printed numbers. The green-yellow core isto be used solely as a PE (protective earth)or PEN (protective earth and neutral) con-ductor. The blue core is provided for useas a neutral conductor.The blue core may be used as a phaseconductor if the cable has a concentricconductor or if a neutral conductor isnot required.

Concentric conductors, screens,armor and metal sheaths

Low-voltage cables are provided withconcentric conductors as protection fromcontact if there is a possibility of the ca-bles being exposed to mechanical damage.Concentric conductors are made of copper.The data on the cross-sectional area in thetype designation code always refer to thematerial of the phase conductors.For cables with concentric conductors indistribution systems, the wires of the con-centric conductors are laid in waveform(CEANDER conductor) on the inner cover-ing. These conductors facilitate the instal-lation of the branch joints because theconcentric conductor can easily be liftedup and bundled at one side. It also en-sures that there is sufficient space forconnecting branches to the underlyingphase conductors without having to cutthe CEANDER conductor.Screens are compulsory for all cable typesabove 0.6/1 kV. Screens shall consist ofcopper. In case of single-core cables multi-core cables may have individual screenedcores or a common screen. In multi-corecables a steel wire armor may also beused as a common screen. The screenswhich are always grounded ensure protec-tion from contact and carry the leakageand ground-fault currents. According toDIN VDE 0276-620 the nominal cross-sectional area of the screens (geometricalcross-sectional area) may not fall belowthe values in the following table (Fig. 5).

25 to 120

150 to 300

400, 500

16

25

35

Nominal cross-sectional area ofphase conductor

Nominal cross-sectional of thescreen*

mm2 mm2

* A nominal cross-sectional area of the screen of 16 mm2

is permissible for multi-core cables laid in the ground andsingle-core cables with a phase conductor cross-sectionalarea of up to 185 mm2 and 240 mm2 respectively, provid-ed that these values are compatible with ground-fault ordouble ground-fault currents.

Fig. 5

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5/5Siemens Power Engineering Guide · Transmission & Distribution

Power Cables – General

side and bonded to a black PE sheath. Allother high-voltage cable types are usuallyalso combined with a PE sheath becauseof its high mechanical stability.Only if there are requirements for flameretardance according to IEC 332-2 shoulda PVC sheath be applied instead of or inaddition to the commonly used PE sheath.

Products

Low- and medium-voltage cables

Information on low-voltage and medium-voltage cables with voltages or construc-tions not listed in this Engineering Guide,for example paper-insulated cables, canbe obtained from Dept. EV SK2.

For further information please contact:

Fax: ++49-9131-73 2455

SIENOPYR cables have the followingexcellent characteristics: Reduced fire propagation performance:

Even in the case of large grouping andvertical installation of cables, the spreadof fire by cables is prevented (tests ac-cording to IEC 332-3).

Corrosivity:No subsequential fire damage becausethe materials of these cables are halo-gen-free and the gas emission is non-corrosive (tests according to IEC 754-2).

Low smoke density:Fire-fighting and rescue operations aredecisively facilitated (tests according toIEC 1034).

Flexible cables which are used for instal-lations in high-rise and industrial high-risebuildings, for connecting mobile equipmentas well as for internal wiring of equipmentcan be obtained from Dept. EV SK 3.For further information please contact:

Fax: ++ 49-9131-7310 92

High- and Extra-High-Voltage Cablesup to 290/500 kV and Accessories

Information on high-voltage cables andaccessories is available from SiemensDept. EV SK1 V.

For further information please contact:

Fax: ++ 49-9131-73 4744

High-voltage cables are laid and installedby Siemens on a contractual basis. Thiscovers all tasks from route planning up tothe final voltage test to be carried out. Thisis due to the very special requirementseach customer has for a high-voltage cablecircuit and the specific solutions Siemenscan offer to fulfil these requirements.

Application

The cables and accessories shown on thefollowing pages are designed for all kindsof high-voltage transmission of electricalenergy. The main requirements for theseapplications are as follows: Low loss factor tan delta:

This is for low dielectric losses to mini-mize heating.

Thermal stability of insulation:This is for a uniform loss factor at allload fluctuations and overvoltagesoccurring in operation.

Electrical stability of insulation:This is for freedom from partial dis-charge through effective preventionof ionization in voids.

All these main requirements are fulfilledby XLPE-insulated PROTOTHEN X cablesand low-pressure oil-filled cables, togetherwith Siemens accessories for high-voltagecables shown in Fig. 37 to 44 by examplesto demonstrate their typical constructionalelements.

Fig. 6: Installation of low- and medium-voltage cablesin an industrial area

Fig. 7: Laying of a 20 kV single-corePROTOTHEN X Cable

Fig. 9: 110 kV single-core PROTOTHEN X cables withoutdoor sealing ends

Fig. 8: Low-pressure oil-filled cables to switchgear byGIS-type sealing ends

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5/6 Siemens Power Engineering Guide · Transmission & Distribution

Power Cables – General

Product Overview –Selection Guide

Overview of main cable types and a guidefor the selection of cable according to volt-age, insulation and metallic coverings.

Oil-impregnatedpaper insulation

Page 7

Page 7

Page 8

Page 11

Page 9

Page 9

Page 10

Page 10

Page 11

Page 12

Page 12

Page 8

Page 21

Page 21

Page 22

Page 22

High-voltagecable

64/110 kV Single-core XLPEinsulation

Screen Lamina-ted PE-sheath

Lead sheath

Corrugatedaluminum-sheath

Low-andmedium-voltagePowercables

0.6/1 kV Multi-core PVCinsulation

PVCsheath

Steel armor

No screen

Concentricconductor

160/275 kV

290/500 kV

XLPEinsulation

3.6/6 kV

6/10 kV

12/20 kV

6/10 kV12/20 kV18/30 kV

Three-core

Single-core

PVCinsulation

ScreenXLPEinsulation

PE-sheath

Steel armor

Steel armor

Controlcables

0.6/1 kV Multi-core PVCinsulation

No screen

Screen

No screen

PVCsheath

Lead +PVC

NYY

NYCWY

2XFY

N2XH

NYFGY

N2XSEY

2XSEYFY

N2XSY

N2XS2Y

NYY

NYCY

YKYRY

2XS(FL)2Y

2XK2Y

2XKLDE2Y

NÖKLDE2Y

Screen

No screen EVA-sheath

PVCsheath

Fig. 10: Overview of main cable types

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5/7Siemens Power Engineering Guide · Transmission & Distribution

Multi-Core PROTODUR Power Cables 0.6/1 kV

NYY

U0/U = 0.6/1 kV (Um = 1.2 kV)

acc. toDIN VDE 0276-603, HD 603, IEC 502

Design

Power cables with copper conductor, PVC insulation and PVC sheath.

Application

Mainly for power stations, industrialplants and substations. Usually laid in-doors, in ducts and outdoors. May also belaid in the ground where damage (e. g.from pickaxes) is unlikely.

Current-Carrying Capacity

acc. to DIN VDE 0276-603,based on IEC 287Permissible operating temp. 70 °CPermissible short-circuit temp. 160 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A58-X-7600Four-core PROTODUR cables,type NYY for 0.6/1 kV2. Cable book:Power Cables and their Application,Part 2, pp. 226, 227

Application

Mainly for distribution systems. Also forpower stations, industrial plants and sub-stations.

Current-Carrying capacity

acc. to DIN VDE 0276-603, HD 603,based on IEC 287Permissible operating temp. 70 °CPermissible short-circuit temp. 160 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A28-X-7600PROTODUR cables, type NYCY/NYCWYfor 0.6/1 kV2. Cable book:Power Cables and their Application,Part 2, pp. 232, 233

Multi-Core PROTODUR Power Cables 0.6/1 kVwith concentric waveform conductor

NYCWY

U0/U = 0.6/1 kV (Um = 1.2 kV)

acc. toDIN VDE 0276-603, HD 603, IEC 502

Design

Power cables with copper conductor, PVC insulation, concentric copper conductor

laid in waveform and PVC sheath.

Medium- and Low-Voltage Cablesup to 45 kV

Fig. 11

Fig. 12

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5/8 Siemens Power Engineering Guide · Transmission & Distribution

Medium- and Low-Voltage Cablesup to 45 kV

Application

For very severe operating, laying andinstallation conditions. The armor with-stands tensile stresses such as thoseoccurring on step gradients and in miningsubsidence areas. Suitable as river andsubmarine cables.

Current-Carrying Capacity

on requestPermissible operating temp. 90 °CPermissible short-circuit temp. 250 °C(for short circuit durations up to 5 s)

Multi-Core PROTODUR Control Cables 0.6/1 kVwith round steel wire armor

YKYRY

U0/U = 0.6/1 kV (Um = 1.2 kV)

acc. to IEC 502

Design

Control cable with copper conductor, PVC insulation, with lead sheath, round wire armoring and PVC sheath.

Application

For filling stations, refineries and other in-stallations where the effects of oil, sol-vents, etc. are to be expected. The leadsheath protects the installation from sucheffects.

Current-Carrying Capacity

on requestPermissible operating temp. 70 °CPermissible short-circuit temp. 160 °C(for short-circuit durations up to 5 s)

Multi-Core PROTOTHEN X Power Cables 0.6/1 kVwith flat steel wire armor

Fig. 13

2XFY

U0/U = 0.6/1 kV (Um = 1.2 kV)

acc. to IEC 502

Design

Power cable with copper conductor, XLPE insulation, with flat steel-wire armor and PVC sheath.

Fig. 14

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5/9Siemens Power Engineering Guide · Transmission & Distribution

N2XSEY

U0/U = 6/10 kV (Um = 12 kV)

acc. toDIN VDE 0276-620, HD 620, IEC 502

Design

Power cables with copper conductor, extruded firmly bonded semi-

conductive layers under and overthe XLPE insulation, with

individually screened cores and PVC sheath.

NYFGY

U0/U = 3.6/6 kV (Um = 7.2 kV)

acc. toDIN VDE 0271, IEC 502

Design

Power cable with copper conductor, PVC insulation, flat steel-wire armor and PVC sheath.

3-Core PROTODUR Cables 3.6/6 kVwith flat steel wire armor

Application

Mainly in power stations, industrial plantsand substation stations.For laying outdoors, in ducts and indoors,resistant to tensile stress, suitable as riverand submarine cables.

Current-Carrying Capacity

on requestPermissible operating temp. 70 °CPermissible short-circuit temp. 160 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A50-X-76003-core PROTODUR cables,type NYFGY for 3.6/6 kV2. Cable book:Power Cables and their Application,Part 2, pp. 248, 249

Fig. 16

Medium- and Low-Voltage Cablesup to 45 kV

Fig. 15

Application

Mainly in power stations, industrial plantsand substations and in distribution systemswhere high thermal stresses occur. For lay-ing outdoors, in ducts and indoors.

Current-Carrying Capacity

acc. to DIN VDE 0276-620, HD 620,based on IEC 287Permissible operating temp. 90 °CPermissible short-circuit temp. 250 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A1-X-76003-core PROTOTHEN X cables,type N2XSEY for 6/10 kV

3-Core PROTOTHEN X Cables 6/10 kVwith copper wire screen on each core

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5/10 Siemens Power Engineering Guide · Transmission & Distribution

2XSEYFY

U0/U = 12/20 kV (Um = 24 kV)

acc. to IEC 502Design

Power cable with copper conductor, extruded firmly bonded semi-

conductive layers under and over theXLPE insulation, with

individually screened cores,PVC separation sheath with

flat steel wire armor and PVC sheath.

N2XSY

U0/U = 6/10 kV (Um = 12 kV)U0/U = 12/20 kV (Um = 24 kV)U0/U = 18/30 kV (Um = 36 kV)

acc. toDIN VDE 0276-620, HD 620, IEC 502

Medium- and Low-Voltage Cablesup to 45 kV

Single-Core PROTOTHEN X Cableswith copper wire screen

Application

Mainly in power stations, industrialplants and substations. For laying out-doors, in ducts and indoors.

Current-Carrying Capacity

acc. to DIN VDE 0276-620, HD 620,based on IEC 287Permissible operating temp. 90 °CPermissible short-circuit temp. 250 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A2-X-76001-Core PROTOTHEN X Cables 6/10 kVOrder No. E50001-U511-A48-X-76001-Core PROTOTHEN X Cables 12/20 kVOrder No. I115/111I8-101-021-Core PROTOTHEN X Cables 18/30 kV2. Cable book:Power Cables and their Application,Part 2, pp. 258–265

Fig. 18

Application

Mainly in industrial plants, power stationsand public distribution systems, wherehigh thermal and mechanical stressesoccur.Note: This type is available on request forthe full range af cable types incorporatingaluminum conductors, screens of coppertapes, armor of galvanized round steelwires or steel tapes, outer sheath of PEor any combination of these.

Current-Carrying Capacity

on requestPermissible operating temp. 90 °CPermissible short-circuit temp. 250 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A43-X-76003-core PROTOTHEN X cables with wirescreen and galvanized flat steel-wirearmor, type 2XSEYFY for 12/20 kV

3-Core PROTOTHEN X Cables 12/20 kVwith copper wire screen and flat steel wire armoring

Fig. 17

Design

Power cable with copper conductor, extruded firmly bonded semi-

conductive layers under and overthe XLPE insulation,

copper wire screen and PVC sheath.

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5/11Siemens Power Engineering Guide · Transmission & Distribution

N2XH

U0/U = 0.6/1 kV (Um = 1.2 kV)

acc. toDIN VDE 0266 Part 2 (HD 604.5G)

Medium- and Low-Voltage Cablesup to 45 kV

Application

SIENOPYR cables with improved charac-teristics in the case of fire are mainly usedin buildings and installations with increasedsafety risks and high concentration ofpeople or valuable contents.The application of these cables shouldbe regarded as a measure for preventivefire protection in: Hospitals Hotels Underground and local rapid transit

rail systems SchoolsSIENOPYR cables are intended for instal-lation indoors and outdoors.

Current-Carrying Capacity

on requestPermissible operating temp. 90 °CPermissible short-circuit temp. 250 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A56SIENOPYR Cables N2XH for 0.6/1 kV2. Cable book:Power Cables and their Application,Part 2, pp. 271–277

Fig. 20

SIENOPYR Power CablesHalogen-Free Cables with Improved Characteristicsin Case of Fire

Application

Mainly for industrial and distributionsystems, for laying in the ground. Whenthese cables are laid indoors or in ducts, itmust be noted that polyethylene-sheathedcables are not flame-retardant accordingto DIN VDE 0472, Part 804, Test method B

Current-Carrying Capacity

To DIN VDE 0276-620, HD 620,based on IEC 287Permissible operating temp. 90 °CPermissible short-circuit temp. 250 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A65-X-76001-Core PROTOTHEN X Cables 6/10 kVOrder No. A19100-I11-A41-X-76001-Core PROTOTHEN X Cables 12/20 kVOrder No. A19100-I11-A42-V1-76001-Core PROTOTHEN X Cables 18/30 kV2. Cable book:Power Cables and their Application,Part 2, pp. 258–265

Single-Core PROTOTHEN X Cableswith copper wire screen

N2XS2Y

U0/U = 6/10 kV (Um = 12 kV)U0/U = 12/20 kV (Um = 24 kV)U0/U = 18/30 kV (Um = 36 kV)

acc. toDIN VDE 0276-620, HD 620, IEC 502

Fig. 19

Design

Power cables with copper conductor, XLPE insulation, inner covering and EVA sheath.

Design

Power cables with copper conductor, extruded firmly bonded semiconduc-

tive layers under and over the XLPEinsulation, with

copper wire screen and PE sheath.

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5/12 Siemens Power Engineering Guide · Transmission & Distribution

Multi-Core PROTODUR Control Cables 0.6/1 kV

NYY

U0/U = 0.6/1 kV (Um = 1.2 kV)

acc. toDIN VDE 0276-627, HD 627, IEC 502

NYCY

U0/U = 0.6/1 kV (Um = 1.2 kV)

acc. toDIN VDE 0276-627, HD 627, IEC 502

Design

Control cable with copper conductor, PVC insulation (numbered cores) and PVC sheath.

Medium- and Low-Voltage Cablesup to 45 kV

Application

Transmission of control pulses, measuredvalues, etc. in power stations, industrialplants, installation indoors, etc., in ducts inthe ground and outdoors. The printed num-bers on the cores simplify identificationand speed up installation, as ringing out isnot necessary. When long runs are laid inthe ground, inductive effects are to betaken into account.

Current-Carrying Capacity

acc. to DIN VDE 0276-627, HD 627,based on IEC 287Permissible operating temp. 70 °CPermissible short-circuit temp. 160 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A63-X-7600PROTODUR control cables,type NYY for 0.6/1 kV2. Cable book:Power Cables and their Application,Part 2, pp. 246, 247

Fig. 21a

Design

Control cable with copper conductor, PVC insulation (numbered cores), concentric copper conductor and PVC sheath.

Fig. 21b

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5/13Siemens Power Engineering Guide · Transmission & Distribution

The service reliability of a cable installationdepends, among other things, on the appli-cation of suitable accessories and the care-ful installation of accessories. Due to ourextensive manufacturing program, suitableaccessories can be supplied for each cableand each application.

General

Voltage classes:

Low voltage up to 1.2 kV; Medium voltage > 1.2 kV up to 36 kV

Cable joints ...

... connect lengths of cable in long trans-mission routes as straight joints for con-nection and branch joints for connectingservice cable and must fulfill the followingfunctions: Connection of the conductors Insulation of the conductors and,

especially in medium-voltage cables,re-establishment of the elementsof the cable

Protection against all ambient conditionsof the ground

Establishment of branch points forservice cables in low-voltage networks

Terminations ...

... form the termination points of cable andserve as a connection to electric apparatusor machines or switchgear. Depending onthe system rated voltage and the cableconstruction, the following objectives mustbe met:

Connection of the conductors. Sealing of the cable against ambient

influences. Protection of core insulation

(e.g. against UV radiation). Controlled reduction of the electric field

strength on medium-voltage cable. Insulation from grounding parts.

Conductor Connection:

Hexagonal compression crimping is re-commended. Other kinds of compressioncrimping are possible.

Outer conductive layer ...

... will be removed in an approved mannerwith a suitable stripping tool.

Accessories for Low- and Medium-Voltage Cables

Powercable

Branch joint

Controlcables

PA, PAKGNKA2

Fig. 23Fig. 23

Page 5/14Page 5/14

Voltage-proof end joint SKEM Fig. 24 Page 5/14

Straight joint SKSM, SKSM-C, GNKVPV

Fig. 25Fig. 27

Page 5/15Page 5/16

Termination SKSA, SKSE, GNKI Fig. 26 Page 5/15

Straight joint PV Fig. 27 Page 5/16

Termination GHKI/GHKF 7.2 Fig. 28 Page 5/16

Straight joint WP 10/20/30 Fig. 29 Page 5/17

Termination GHKI/GHKF 12/24IAES

Fig. 28Fig. 32

Page 5/16Page 5/18

Straight joint WP 10/20/30WPS 10/20/30GHSV 12/24/36

Fig. 29Fig. 30Fig. 31

Page 5/17Page 5/17Page 5/18

Termination GHKI/GHKF 12/24/36IAES 10/20/30FAE 10/20

Fig. 33Fig. 34Fig. 35

Page 5/19Page 5/19Page 5/20

Boots FHKG/FHKW Fig. 36 Page 5/20

Straight joint SKSM-STPV

Fig. 25Fig. 27

Page 5/15Page 5/16

Multi-core

3-core

Single-core

Multi-core

0.6/1 kVNYYNYCWY2XFY

3.6/6 kVNYFGY

6/10 kVN2XSEY12/20 kV2XSEYFY

6/10 kV12/20 kV18/30 kVN2XSYN2XS2Y

0.6/1 kVNYYNYGYYKYRY

Fig. 22: Overview of Acessories for Low- and Medium-Voltage Cable

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5/14 Siemens Power Engineering Guide · Transmission & Distribution

Voltage-Proof End Joint for multi-core cable 0.6/1 kV

PA/PAK + GNKA 2

Design

PROTOLIN cast-resin-filledplastic mold.

PA joint: using single clamps. PAK joint: Cores connected by compact

locking collar without removing theinsulation.

Application

In ground, ducts and in air.

Installation

Without special tools.

Design

GNKA 2 consists of sealant mats placedaround the compact locking collar. A fiber-reinforced sleeve with coating of sealantis used as outer protection.Cores connected by compact lockingcollar without removing the insulation.

Application

In ground, ducts and in air.

Installation

With gas torch or hot air blower.

Design

Heatshrinkable cross-linked polyolefinend caps inside coated with a hot meltadhesive.

Application

To sealing cables ends, where the cableis connected to voltage.

In ground, ducts and in air.

Installation

With gas torch or hot air blower.

Accessories for Low- and Medium-Voltage Cables

Branch Joint for multi-core cable 0.6/1 kV

Fig. 23

SKEM

Fig. 24

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5/15Siemens Power Engineering Guide · Transmission & Distribution

Accessories for Low- and Medium-Voltage Cables

Straight Joint for multi-core cable 0.6/1 kV

SKSM/SKSM-C/SKSM-ST/GNKV

SKSA, SKSE, GNKI

Design

Heatshrinkable cross-linked polyolefintubes coated with a special hot meltadhesive on the inside.The number of inner tubes depends on thenumber of cable cores.

Application

In ground, ducts and in air. SKSM for multi-core power cables, SKSM-C for power cables with

concentric neutral, SKSM-ST for control cables.

Installation

With gas torch or hot air blower.

Fig. 26

Design

SKSA: breakout consist of heat shrink-able cross-linked polyolefin hot meltcoated and serves to protect the cablespreader area against moisture.

SKSE and GNKI: additional with heat-shrinkable tubes for protection and seal-ing the cable cores. In case of metalshielded cables, the connection materialare included in the kit.

Application

Outdoor and indoor.

Installation

With gas torch or hot air blower.

Termination for multi-core cable 0.6/1 kV

Fig. 25

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5/16 Siemens Power Engineering Guide · Transmission & Distribution

PV

GHKI/GHKF 7.2/12/24

Termination for 3-core polymeric cable 3.6/6 up to 18/30 kV

Fig. 28

Design

PROTOLIN cast-resin-filled plastic.The size of joint depends on the numberof cable cores.

Application

All areas.

Accessories for Low- and Medium-Voltage Cables

Fig. 27

Straight Joint for 3-core and multi-core cable 0.6/1 up to 3.6/6 kV

Design

Heatshrinkable, track-resistant, cross-linkedpolyolefin tubes and breakout, coated withsealing adhesive.

Application

GHKI-Indoor and GHKF-Outdoor termina-tions can be used in all applications.

Installation

With gas torch or hot air blower.

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5/17Siemens Power Engineering Guide · Transmission & Distribution

Accessories for Low- and Medium-Voltage Cables

WP 10/20/30

WPS 10/20/30

Design

Shielded joint wrapping which is mechani-cally protected by a plastic tube filled withPROTOLIN cast resin.

Application

In ground, ducts and in air.

Design

Shielded joint wrapping which is mechani-cally protected by a thick-walled heat-shrinkable tube.

Application

In ground, ducts and in air.

Installation

Without special tools.

Straight Joint for 1- and 3-core polymeric cable 10/12 – 18/30 kV

Fig. 29

Straight Joint for 1-core polymeric cable 10/12 up to 18/30 kV

Fig. 30

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5/18 Siemens Power Engineering Guide · Transmission & Distribution

Accessories for Low- and Medium-Voltage Cables

GHSV 12/24/36

IAES 10

Design

Track-resistant, silicon rubber insulatorwith an integrated control deflector forcontrolling the electrical field.

Application

IAES indoor terminations can be usedin switchgear and transformer stations.

Installation

Without special tools.

Design

Heatshrinkable insulation tubes combinedwith stress control components and seal-ing tapes or coatings protected by a thick-walled heatshrinkable tube.

Application

In ground, ducts and in air.

Straight Joint for 1- and 3-core polymeric cable 10/12 – 18/30 kV

Fig. 31

Termination

Fig. 32

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5/19Siemens Power Engineering Guide · Transmission & Distribution

Accessories for Low- and Medium-Voltage Cables

Terminations

GHKI/GHKF 12/24/36

IAES 10/20/30

Design

Track-resistant, silicon rubber insulator withan integrated control deflector for control-ling the electrical field.

Application

IAES indoor terminations can be used inswitchgear and transformer boxes.

Installation

Without special tools.

Design

Heatshrinkable, track-resistant, cross-linkedpolyolefin tubes and breakout, coated withsealing adhesive.

Application

GHKI-Indoor, GHKF-Outdoor used inswitchgear and transformer stations.

Installation

Gas torch or hot air blower.

Fig. 33

Termination

Fig. 34

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5/20 Siemens Power Engineering Guide · Transmission & Distribution

Accessories for Low- and Medium-Voltage Cables

Termination

FAE 10/20

Design

Track-resistant, silicon rubber insulator withan integrated control deflector for control-ling the electrical field.

Application

FAE outdoor terminations can be used inswitchgear and transformer stations.

Installation

Without special tools.

Seperable connectors Design

Heatshrinkable, track-resistant, insulationmolded parts sealed with track-resistantadhesive.

Application

The boots can protect the connectionbushings into transformer and motor con-nection boxes.

All the accessories are listed in theRXS catalogOrder No.: A 45050-W2165-D7-X-7600

For further information please contact:

Fax: ++49-2331- 357118

Fig. 35

Fig. 36

FHKG, FHKW

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5/21Siemens Power Engineering Guide · Transmission & Distribution

Fig. 37

2XS(FL)2Y

64/110 kV (Um = 123 kV)

according to IEC 840

Single-core XLPE-insulated cable 64/110 kVwith laminated sheath

Design

Cable with Conductor Conductor screen XLPE insulation Insulation screen Semiconductive nonwoven

swelling tape Screen of copper wires Copper contact helix PE-coated Al tape and PE sheath

(laminated sheath)

Current-Carrying Capacity

on requestPermissible operating temp. 90 °CPermissible short-circuit temp. 250 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A5-X-7600Cables and Accessories for High- andExtra-High-Voltages

Design

Cable with Conductor Conductor screen XLPE insulation Insulation screen Semiconductive nonwoven

swelling tape Lead sheath Compound PE sheath

Current-Carrying Capacity

on requestPermissible operating temp. 90 °CPermissible short-circuit temp. 250 °C(for short-circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A5-X-7600Cables and Accessories for High- andExtra-High-Voltages

Single-core XLPE-insulated cable 160/275 kVwith lead sheath

2XK2Y

160/275 kV (Um = 300 kV)

based on IEC 840

Fig. 38

High-Voltage Cables up to 290/500 kV

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5/22 Siemens Power Engineering Guide · Transmission & Distribution

NÖKLDE2Y

290/500 kV (Um = 525 kV)

according to IEC 141

Fig. 40

Design

Cable with Hollow conductor Carbon black paper Paper insulation Carbon black paper and metallized black

paper Fabric tape with interwoven copper

wires Corrugated aluminum sheath Plastic tape in compound and PE sheath

Current-Carrying Capacity

on requestPermissible operating temp. 85 °CPermissible short-circuit temp. 160 °C(for short circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A5-X-7600Cables and Accessories for High- andExtra-High-Voltages

Fig. 39

2XKLDE2Y

290/500 kV (Um = 525 kV)

based on IEC 840

Single-core XLPE-insulated cable 290/500kVwith Milliken conductor and corrugated aluminum sheath

Design

Cable with Milliken conductor Conductor screen XLPE insulation Insulation screen Semiconductive bedding layer Fabric tape with

interwoven copper wires Corrugated aluminum sheath Plastic tape in compound and

PE sheath

Current-Carrying Capacity

on requestPermissible operating temp. 90 °CPermissible short-circuit temp. 250 °C(for short circuit durations up to 5 s)

Publications:

1. Leaflets:Order No. E50001-U511-A5-X-7600Cables and Accessories for High- andExtra-High-Voltages

High-Voltage Cables up to 290/500 kV

Single-core low pressure oil filled cable 290/500 kVwith corrugated aluminum sheath

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5/23Siemens Power Engineering Guide · Transmission & Distribution

Connectingtube

Corona shield

Filling compound

Slip-on stress cone

Insulator

Copper entrance bell

Mechanical protection

Outlet screwor valve connection

Aluminum-baseplate

Insulatingring

Arcinghorn

Slip-onstress cone

Fillingcompound

Copperentrance bell

Mechanicalprotection

Porcelaininsulator

Coronashield

Connectorstalk

Supportbase

Outlet screwor valveconnection

Accessories for High-Voltage Cablesup to 290/500 kV

Typical design of outdoor-type sealing end Typical design of transformer-type sealing end

Fig. 42Fig. 41

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5/24 Siemens Power Engineering Guide · Transmission & Distribution

Outlet screwor valve connection

Mechanicalprotection

Connection interfaceaccording to IEC 859

Cast-resin insulator

Filling compound

Slip-onstress cone

Copperentrance bell

Housing

Insulation

Conductor shieldCoaxial cable for cross-bonding

Deflector Deflector

Accessories for High-Voltage Cablesup to 290/500 kV

Fig. 43

Single-core sectionalized joint

Typical design of GIS-type sealing end

Fig. 44

All the accessories are listed in theRXS catalogOrder No.: A 45050-W2165-D7-X-7600

For further information please contact:

Fax: ++49- 2331- 357118

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Siemens Power Engineering Guide · Transmission & Distribution6/2

by means of SCADA-like operation controland high-performance, uniformly operablePC tools

Rationalisation of operation

by means of integrationof many functionsinto one unit and compact equipment design

Savings in terms of space and costs

by means of uniform design, coordinatedinterfaces and universally identical EMC

Simple planning and operational reliability

High levels of reliability and availability

Efficient parameterization and operation by means of PC tools with uniform operatorinterface

by means of type-tested system technology,complete self-monitoring and the use ofpoven technology– 20 years of practical experience with

digital protection, 50,000 devicesin operation (1996)

– 10 years of practical LSA678 experience,400 substations in operation (1996)

Protection and Substation Control

Fig. 2a: Protection and control in HV GIS switchgear Fig. 2b: Protection and control in bay dedicatedkiosks of an EHV-switchyard

General overview

Three trends have emerged in the sphereof substation secondary equipment: intelli-gent electronic devices (IEDs), open com-munication and operation with a PC.Numerical relays and cumputerized substa-tion control are now state-of-the-art.The multitude of conventional, individualdevices prevalent in the past as well ascomprehensive parallel wiring are beingreplaced by a small number of multifunc-tional devices with serial connections.

One design for all applications

In this respect, Siemens offers a uniform,universal technology for the entire func-tional scope of secondary equipment, bothin the construction and connection of thedevices and in their operation and commu-nication. This results in uniformity of de-sign, coordinated interfaces and the sameoperating concept being establishedthroughout, whether in power system andgenerator protection, in measurement andrecording systems, in substation controland protection or in telecontrol.All devices are highly compact and im-mune to interference, and are thereforealso suitable for direct installation inswitchgear cells. Furthermore, all devicesand systems are largely self-monitoring,which means that previously costly mainte-nance can be reduced considerably.

“Complete technology from onepartner“

The Substation Secondary Equipment Divi-sion of the Siemens Power Transmissionand Distribution Group supplies devicesand systems for: Power System Protection Substation Control Remote Control (RTUs) Measurement and RecordingThis covers all of the measurement, con-trol and protection functions for substa-tions*.Furthermore, our activities cover: Consulting Planning Design Commissioning and ServiceThis uniform technology ”all from onesource“ saves the user time and money inthe planning, assembly and operation ofhis substations.

Fig. 1: The digital substation control system SINAUT LSA implements all of the control, measurement and auto-mation functions of a substation. Protection relays are connected serially

Fig. 3: For the user, “complete technology from one source” has many advantages

Substation

*An exception is revenue-metering. Meters are separate products of our Energy Metering Division.

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Protection and Substation Control

System Protection

Siemens offers a complete spectrum ofmultifunctional, numerical relays for allapplications in the field of network andmachine protection.Uniform design and electromagnetic-inter-ferencefree construction in metal housingswith conventional connection terminals inaccordance with public utility requirementsguarantee simple system design and us-age just as with conventional relays.Numerical measurement techniques en-sure precise operation and necessitate lessmaintenance thanks to their continuousself-monitoring capability.

The integration of additional protectionand other functions, such as real-timeoperational measurements, event and faultrecording, all in one unit economizes onspace, design and wiring costs.Setting and programming of the devicescan be through the integral, plaintext,menu-guided operator display or by usingthe comfortable PC program DIGSI forWindows*.Open serial interfaces, IEC 870-5-103 com-pliant allow free communication with high-er level control systems, including thosefrom other manufacturers.

Thus the on-line measurements and faultdata registered in the protective relayscan be used for local and remote controlor can be transmitted via telephone mo-dem connections to the workplace of theservice engineer.Siemens supplies individual devices aswell as complete protection systems infactory finished cubicles. For complex ap-plications, for example, in the field of extra-high-voltage transmission, type and designtest facilities are available together with anextensive and comprehensive networkmodel using the most modern simulationand evaluation techniques.

Line protectionUnit protection (PW and OF)7SD5

SIMEASMeasuring transducers7KG60

Local and remote controlSINAUT LSA/SINAUT RTU

Measurement andrecording

Protection7**5

SINAUT LSALocal andremote control,centralized version6MB551

SINAUT LSALocal andremote control,decentralized version6MB51/52

Central units6MB51*

SINAUT LSACompact unit6MB552Minicompact unit6MB553

Bay units6MB52*

Remote terminal units

SINAUT RTU6MD2010

Feeder protectionovercurrent/overload relays7SJ5

Line protectiondistance relays7SA5

Busbar protection7SS5 and 7VH8

Generator/motor protection7UM5

Transformer protection7UT5

Protection and substation control

Fault recorders(Oscillostores)P5**

Switchgear interlocking8TK

Fig. 4: Siemens Protection and Substation Control comprises these systems and product ranges

* Windows is a registered product of Microsoft

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Protection and Substation Control

Substation control

The digital substation control systems6MB51/52 (decentralized version) and6MB551 (centralized version) provide allcontrol, measurement and automationfunctions (e.g. transformer tap changing)required by a switching station. They oper-ate with distributed intelligence. Commu-nication between feeder-located devicesand central unit is made via interference-free fiber optic connections.Devices are extremely compact and can bebuilt directly into medium- and high-voltageswitchgear.To input data, set and program the system,the unique PC program LSA-TOOLS isavailable. Parameters and values are inputat the central unit and downloaded to thefield devices, thus ensuring error-free andconsistent data transfer.The operator interface is menu-guided,with SCADA comparable functions, that is,with a level of comfort which was previ-ously only available in a network controlcenter. Optional telecontrol functions canbe added to allow coupling of the systemto one or more network control centers.In contrast to conventional controls, digitaltechnology saves enormously on spaceand wiring. LSA systems are subjected tofull factory tests and are delivered in fullyfunctional condition.

Remote control

Siemens remote control equipment6MB55* and 6MD2010 fulfills all the clas-sic functions of remote measurement andcontrol. Furthermore, because of the pow-erful microprocessors with 32-bit technolo-gy, they provide comprehensive data pre-processing, automation functions and bulkstorage of operational and fault informa-tion.In the classic case, connections to theswitchgear are made through coupling re-lays and transducers. This method allowsan economically favorable solution whenmodernizing or renewing the secondarysystems in older installations. Alternatively,especially for new installations, direct con-nection is also possible. Digital protectiondevices can be connected by serial linksthrough fiber-optic conductors.In addition, the functions ”operating andmonitoring“ can be provided by the con-nection of a PC, thus raising the telecontrolunit to the level of a central station controlsystem. Using the facility of nodal func-tions, it is also possible to build regionalcontrol points so that several substationscan be controlled from one location.

Switchgear interlocking

The digital interlocking system 8TK is usedfor important substations in particular withmultiple busbar arrangements. It preventsfalse switching and provides an additionallocal bay control function which allows fail-safe switching, even when the substationcontrol system is not available. Thereforethe safety of operating personnel andequipment is considerabely enhanced.The 8TK system can be used as a stand-alone interlocked control, or as back-upsystem together with the digital 6MB sub-station control.

Measurement and recording

This segment of our business divisionoffers equipment for the superversion ofpower supply quality (harmonic content,distortion factor, peak loads, power factor,etc.), fault recorders (Oscillostore), datalogging printers and measurement trans-ducers.Stored data can be transmitted manually orautomatically to PC evaluation systemswhere it can be analysed by intelligent pro-grams. Expert systems are also appliedhere. This leads to rapid fault analysis andvaluable indicators for the improvement ofnetwork reliability.For local bulk data storage and transmis-sion, the central processor DAKON canbe installed at substation level. Data trans-mission circuits for analog telephone ordigital ISDN networks are incorporated asstandard. Connection to local- or wide-areanetworks (LAN, WAN) is equally possible.To complete the spectrum, we have theSIMEAS series of compact and powerfulmeasurement transducers with analog anddigital outputs.

Advantages for the user

The concept of ”Complete technologyfrom one partner“ offers the user manyadvantages: High-level security for his systems

and operational rationalization possibili-ties– through powerful system solutions

with the most modern technology Space and cost savings

– through integration of many functionsinto one unit and compact equipmentpackaging

Simple planning and secure operation– through unified design, matched inter-

faces and EMI security throughout

Rationalized programming and handling– through menu-guided PC Tools and

unified keypads and displays High-level operational security and avail-

ability– through continuous self-monitoring

and proven technology:– 20 years digital relay experience (ap-

proximately 50,000 units in operation)– 10 years of SINAUT LSA substation

control (400 systems in operation) Rapid problem solving

– through comprehensive advice andfast response from local sales andworkshop facilities worldwide.

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Protection and Substation Control

Application hints

All named devices and systems for pro-tection, metering and control are designedto be used in the harsh environment ofelectrical substations, power plants andthe various industrial application areas.When the devices were developed, specialemphasis was placed on EMI. The devicesare in accordance with IEC255 standards.Detailed information is contained in thedevice manuals.Reliable operation of the devices is notaffected by the usual interference fromthe switchgear, even when the device ismounted directly in a low-voltage compart-ment of a medium-voltage cubicle.It must, however, be ensured that the coilsof auxiliary relays located on the samepanel, or in the same cubicle, are fittedwith suitable spike quenching elements(e.g. free-wheeling diodes).When used in conjunction with switchgearfor 100 kV or above, all external connectioncables should be fitted with a screengrounded at both ends and capable of car-rying currents. That means that the crosssection of the screen should be at least4 mm2 for a single cable and 2.5 mm2 formultiple cables in one cable duct.All equipment proposed in this guideis built-up either in closed housings(type 7XP20) or cubicles with protectiondegree IP51 according to IEC 529: Protected against access to dangerous

parts with a wire Sealed against dust Protected against dripping water

Climatic conditions:

Permissible temperature duringservice–5 °C to +55 °Cpermissible temperature during storage–25 °C to +55 °Cpermissible temperature during transport–25 °C to +70 °CStorage and transport with standardworks packaging!

Permissible humidityMean value per year ≤ 75% relative hu-midity; on 30 days per year 95% relativehumidity; Condensation not permissible!

We recommend that units be installedsuch that they are not subjected to directsunlight, nor to large temperature fluctua-tions which may give rise to condensation.

Mechanical stress

Vibration and shock during operation

Standards:IEC 255-21 and IEC 68-2

Vibration– sinusoidalIEC 255-21-1, class 1– 10 Hz to 60 Hz:

± 0.035 mm amplitude;IEC 68-2-6– 60 Hz to 150 Hz:

0.5 g accelerationsweep rate 10 octaves/min20 cycles in 3 orthogonal axes

Vibration and shock during transport

Standards:IEC 255-21and IEC 68-2

Vibration– sinusoidalIEC 255-21-1, class 2– 5 Hz to 8 Hz:

± 7.5 mm amplitude;IEC 68-2-6– 8 Hz to 150 Hz: 2 g acceleration

sweep rate 1 octave/min20 cycles in 3 orthogonal axes

ShockIEC 255 -21-2, class 1IEC 68 -2-27

Insulation tests

Standards:IEC 255-5– High-voltage test (routine test)

2 kV (rms), 50 Hz– Impulse voltage test (type test)

all circuits, class III5 kV (peak); 1,2/50 µs; 0,5 J; 3 positiveand 3 negative shots at intervals of 5 s

Fig. 5: Installation of the numerical protection in thedoor of the low-voltage section of medium-voltage cells

Electromagnetic compatibility

EC Conformity declaration (CE mark):

All Siemens protection and control prod-ucts, recommended in this guide, complywith the EMC Directive 99/336/EEC of theCouncil of the European Community andfurther relevant IEC 255 standards on elec-tromagnetic compatibility.All products carry the CE mark.

EMC tests; immunity (type tests)

Standards:IEC 255-22 (product standard)EN 50082-2 (generic standard)

High frequencyIEC 255-22-1 class III– 2.5 kV (peak);

1 MHz; γ = 15 µs;400 shots/s;duration 2 s

Electrostatic dischargeIEC 255-22-2 class IIIand EN 61000-4-2 class III– 4 kV contact discharge;

8 kV air discharge;both polarities;150 pF; Ri = 330 Ohm

Radio-frequency electromagnetic field,nonmodulated;IEC 255-22-3 (report) class III– 10 V/m; 27 MHz to 500 MHz

Radio-frequency electromagnetic field,amplitude-modulated;ENV 50140, class III– 10 V/m; 80 MHz to 1000 MHz, 80%;

1 kHz; AM Radio-frequency electromagnetic field,

pulse-modulated;ENV 50140/ENV 50204, class III– 10 V/m; 900 MHz;

repetition frequency 200 Hz;duty cycle 50%

Fast transientsIEC 255-22-4 and EN 61000-4-4, class III– 2 kV; 5/50 ns; 5 kHz;

burst length 15 ms; repetition rate300 ms; both polarities;Ri = 50 Ohm; duration 1 min

Conducted disturbances induced byradio-frequency fields HF,amplitude-modulatedENV 50141, class III– 10 V; 150 kHz to 80 MHz;

80%; 1kHz; AM Power-frequency magnetic field

EN 61000-4-8, class IV– 30 A/m continuous;

300 A/m for 3 s; 50 Hz

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C.t. designaccording to ANSI/IEEE C 57.13

Class C of this standard defines the c.t. byits secondary terminal voltage at 20 timesnominal current, for which the ratio errorshall not exceed 10%. Standard classesare C100, C200, C400 and C800 for 5 Anominal secondary current.This terminal voltage can be approximatelycalculated from the IEC data as follows:

Protection and Substation Control

EMC tests; emission (type tests)

Standard:EN 50081-2 (generic standard)

Interference field strength CISPR 11,EN 55011, class A– 30 MHz to 1000 MHz

Conducted interference voltage,aux voltage CISPR 22, EN 55022,class B– 150 kHz to 30 MHz

Instrument transformers

Instrument transformers must complywith the applicable IEC recommendationsIEC 185 (c.t.) and 186 (p.t.), ANSI/IEEEC57.13 or other comparable standards.

Potential transformers

Potential transformers (p.t.) in single- ordouble-pole design for all primary voltageshave single or dual secondary windings of100, 110 or 120 V/ 3, with output ratingsbetween 10 and 300 VA, and accuraciesof 0.2, 0.5 or 1% to suit the particularapplication. Primary BIL values are select-ed to match those of the associatedswitchgear.

Current transformers

Current transformers (c.t.) are usually ofthe single-ratio type with wound or bar-type primaries of adequate thermal rating.Single, dual or triple secondary windings of1 or 5 A are standard.1 A rating however should be preferred,particularly in HV and EHV stations, to re-duce the burden of the connecting leads.Output power (rated burden in VA), accura-cy, and saturation characteristics (accuracylimiting factor) of the cores and secondarywindings must meet the particular applica-tion.The c.t. classification code of IEC is usedin the following:

Measuring cores

They are normally specified with 0.5% or1.0% accuracy (class 0.5 M or 1.0 M), andan accuracy limiting factor of 5 or 10.The required output power (rated burden)must be higher than the actually connect-ed burden. Typical values are 5, 10, 15 VA.Higher values are normally not necessarywhen only electronic meters and recordersare connected.A typical specification could be: 0.5 M 10,15 VA.

The required c.t. accuracy-limiting factorKALF can be determined by calculation,as shown in Fig. 6.The overdimensioning factor KOF dependson the type of relay and the primary d.c.time constant. For the normal case, withshort-circuit time constants lower than100 ms, the necessary value for K*ALF canbe taken from the table in Fig. 9.The recommended values are based onextensive type tests.

C.t. design according to BS 3938

In this case the c.t. is defined by the knee-point voltage UKN and the internal second-ary resistance Ri.The design values according to IEC 185can be approximately transferred into theBS standard definition by the followingformula:

Fig. 6: C.t. dimensioning formulas

Cores for revenue metering

In this case, class 0.2 M is normallyrequired.

Protection cores:

The size of the protection core dependsmainly on the maximum short-circuit cur-rent and the total burden (internal c.t. bur-den, plus burden of connecting leads, plusrelay burden).Further, an overdimensioning factor has tobe considered to cover the influence of thed.c. component in the short-circuit current.In general, an accuracy of 1% (class 5 P) isspecified. The accuracy limiting factor KALFshould normally be designed so thatat least the maximum short-circuit currentcan be transmitted without saturation.(d.c. component not considered).This results, as a rule, in rated accuracylimiting factors of 10 or 20 dependent onthe rated burden of the c.t. in relation tothe connected burden. A typical specifica-tion for protection cores for distributionfeeders is 5P10, 15 VA or 5P20, 10 VA.The requirements for protective currenttransformers for transient performance arespecified in IEC 44-6. The recommendedcalculation procedure for saturationfreedesign, however, leads to very high c.t.dimensions.In many practical cases, the c.t.s cannotbe designed to avoid saturation under allcircumstances because of cost and spacereasons, particularly with metal-enclosedswitchgear.The Siemens relays are therefore designedto tolerate c.t. saturation to a large extent.The numerical relays, proposed in thisguide, are particularly stable in this casedue to their integral saturation detectionfunction.

KALF : Rated c.t. accuracy limiting factorK*ALF : Effective c.t. accuracy

limiting factorRBN : Rated burden resistanceRBC : Connected burdenRi : Internal c.t. burden (resistance

of the c.t. secondary winding)

Iscc.max. = Maximum short-circuit currentIN = Rated primary c.t. currentKOF = Overdimensioning factor

RBC + Ri

RBN + Ri

KALF> K*ALF

I scc.max.K*ALF>

IN

KOF

with:

Fig. 7: BS c.t. definition

Fig. 8: ANSI c.t. definition

Example:IEC 185 : 600/1, 15 VA, 5P10, Ri = 4 Ohm

(RNC + Ri) • I 2N • KALFUKN =1.3

BS : UKN = (15 + 4) • 1 • 10 = 146 V1.3

Ri = 4 Ohm

I2N = Nominal secondary current

Example:IEC 185 : 600/5, 25 VA, 5P20,

20Vs.t. max = 20 x 5 A x RBN •

KALF

with:

RBN = PBN

INsec

2and I

Nsec = 5 A, we get

Vs.t. max = PBN • KALF

5

Vs.t. max = 25 • 20 =5

ANSI C57.13:

= 100, i.e. class C100

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Relay burden

The c.t. burdens of the numerical relays ofSiemens are below 0.1 VA and can there-fore be neglected for a practical estimation.Exceptions are the busbar protection 7SS5(1.5 VA) and the pilot wire relays 7SD502(4 VA) and 7SD503 (3 VA + 9 VA per 100 Ohmpilot wire resistance).Intermediate c.t.s are normally no moreapplicable as the ratio adaption for busbarand transformer protection is numericallyperformed in the relay.Analog static relays in gereral also haveburdens below about 1 VA.Mechanical relays, however, have a muchhigher burden, up to the order of 10 VA.This has to be considered when older re-lays are connected to the same c.t. circuit.In any case, the relevant relay manualsshould always be consulted for the actualburden values.

Protection and Substation Control

Fig. 9: Required effective accuracy limiting factor K*ALF

Relay type Minimum K*ALF

o/c protection7SJ511, 512, 551,7SJ60

, at least 20IHigh set point

IN

Transformerdifferential protection7UT512/513

Line differential(fiber-optic) protection7SD511/12

a = 2 for TN ≤ 50 msa = 4 for TN ≤ 100 ms

I scc. max. (close-in fault)

IN

aDistance protection7SA511, 7SA513

I scc. max. (line-end fault)

IN

10

I scc. max. (outflowing current for ext. fault)

IN

Numerical busbarprotection (low impe-dance type) 7SS5

Line differential(pilot wire) protection7SD502/503

=

=

=

=

andI scc. max. (internal fault)

IN

= 4 .[K*ALF

. UN . IN](High voltage)

[K*ALF . UN

. IN](Low voltage)

1

2

1

2<2

andI scc. max. (internal fault)

IN

[K*ALF . IN](line-end 1)1

4<4= 4 .

andI scc. max. (internal fault)

IN

K*ALF (line-end 1)

K*ALF (line-end 2)

4

5<= 4 . 5

4

<

<

<

[K*ALF . IN](line-end 2)

Fig. 10 Fig. 11

Burden of the connection leads

The resistance of the current loop fromthe c.t. to the relay has to be considered:

Example: Stability-verification of thenumerical busbar protection 7SS5

1 A2RBN =

15 VA= 15 Ohm;

1 A2RRelay =

1.5 VA= 1.5 Ohm

15 + 4KALF >

1.8 + 425 = 7.6

600/15 P 10,15 VA,Ri = 4 Ohm

50=I scc.max.

IN

30,000

600=

7SS5

I scc.max. = 30 kA

l = 50 mA = 6 mm2

Result:

The rated KALF-factor (10) is higherthan the calculated value (7.6).Therefore, the stability criterium isfulfilled.

Rl6

=2 0.0179 50

0.3 Ohm=

RBC = Rl + RRelay =

= 0.3 + 1.5 = 1.8 Ohm

Given case:

2K*ALF >

150 = 25

According to Fig. 9:

ARl =

2 ρ l Ohm

l = single conductor lengthfrom the c.t. to the relay in m.

Specific resistance:

ρ = 0.0179 (copper wires)

A = conductor cross sectionin mm2

Ohm m2

m

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Introduction

Siemens is one of the world’s leading sup-pliers of protective equipment for powersystems.Thousands of our relays ensure first-classperformance in transmission and distribu-tion networks of all voltage levels, all overthe world, in countries of tropical heat orarctic frost.For many years, Siemens has also signifi-cantly influenced the development of pro-tection technology. In 1976, the first minicomputer (process

computer) based protection system wascommissioned: A total of 10 systemsfor 110/20 kV substations were suppliedand are still operating satisfactorily today.

Since 1985 we have been the first tomanufacture a range of fully numericalrelays with standardized communicationinterfaces.Today, Siemens offers a complete pro-gram of protective relays for all applica-tions including numerical busbar protec-tion.To date (1996), more than 50,000 numer-ical protection relays from Siemens areproviding successful service, as stand-alone devices in traditional systems oras components of coordinated protec-tion and substation control.Meanwhile, a second-generation inno-vative series has been launched, incor-porating the many years of operationalexperience with thousands of relays,together with users’ requirements,(power authority reommendations).

State of the art

Mechanical and solid-state (static) relayshave been almost completely phased outof our production because numerical relaysare now preferred by the users due totheir decisive advantages: Compact design and lower cost due to

integration of many functions into onerelay

High availability even with less mainte-nance due to integral self-monitoring

No drift (aging) of measuring characteris-tics due to fully numerical processing

High measuring accuracy due to digitalfiltering and optimized measuring algo-rithms

Many integrated add-on functions,for example, for load-monitoring andevent/fault recording

Easy and secure read-out of informationvia serial interfaces with a PC, locally orremotely

Possibility to communicate with higher-level control systems

Fig. 12: Numerical relay range of Siemens

Power System Protection

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Modern protection management

All the functions, for example, of a line pro-tection scheme can be incorporated in oneunit: Distance protection with associated

add-on and monitoring functions Universal teleprotection interface Autoreclose and synchronism check

Protection-related information, can becalled up on-line or off-line such as: Distance to fault Fault currents and voltages Relay operation data (fault detector pick-

up, operating times etc.) Set values Line load data (kV, A, MW, kVAr)To fulfill vital protection redundancy require-ments, only those functions which are in-terdependent and directly associated witheach other are integrated in the same unit.For back-up protection, one or more addi-tional units have to be provided.

Supervisory control

2167NFL792585SMERFRBM

Distance protectionDirectional ground-fault protectionDistance-to-fault locatorAutoreclosureSynchro-checkCarrier interface (teleprotection)Self-monitoringEvent recordingFault recordingBreaker monitor

Breaker monitor

Relay monitor

Fault record

01.10.93

Fault report

BM

Serial link to station – or personal computer

SM ER FR2579FL67N21

to remote line end kA,kV,Hz,MW,MVAr,MVA,

85

Load monitor

All relays can stand fully alone. Thus thetraditional protection concept of separatemain and alternate protection as well asthe external connection to the switchyardremain unchanged.

”One feeder, one relay“ concept

Analog protection schemes have been en-gineered and assembled from individualrelays. Interwiring between these relaysand scheme testing has been carried outmanually in the workshop.Data sharing now allows for the integrationof several protection and protection relatedtasks into one single numerical relay. Onlya few external devices may be required forcompletion of the total scheme. This hassignificantly lowered the costs of engineer-ing, assembly, panel wiring, testing andcommissioning. Scheme failure probabilityhas also been lowered.Engineering has moved from schematicdiagrams towards a parameter definitionprocedure. The documentation is providedby the relay itself. Free allocation of LEDoperation indicators and output contactsprovides more application design flexibility.

Metering included

For many applications, the protective-cur-rent transformer accuracy is sufficient foroperational metering. The additional meter-ing c.t. was more for protection of metersunder system fault conditions. Due to thelow thermal withstand ability of the me-ters, they could not be connected to theprotection c.t.. Consequently, additionalmetering c.t.s and meters are now onlynecessary where high accuracy is required,e.g. for revenue metering.

Fig. 13: Numerical relays, increased information availability

Power System Protection

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On-line remote data exchange

A powerful serial data link provides forinterrogation of digitized measured valuesand other information, stored in the pro-tection units, for printout and furtherprocessing at the substation or systemcontrol level.In the opposite direction, settings may bealtered or test routines initiated from a re-mote control center.For greater distances, especially in outdoorswitchyards, fiber-optic cables are prefera-bly used. This technique has the advantagethat it is totally unaffected by electromag-netic interference.

Off-line dialog with numerical relays

A simple built-in operator panel whichrequires no special software knowledge orcodeword tables is used for parameterinput and readout.This allows operator dialog with the protec-tion relay. Answers appear largely in plain-text on the display of the operator panel.Dialog is divided into three main phases: Input, alternation and readout of settings Testing the functions of the protection

device and Readout of relay operation data for the

three last system faults and the autore-close counter.

Modern system protectionmanagement

A more versatile notebook computer maybe used for upgraded protection manage-ment.The relays may be set in 2 steps. First, allrelay settings are prepared in the officewith the aid of a PC and stored on a floppyor the hard disk. At site, the settings canthen be transferred from a portable PC intothe relay. The relay confirms the settingsand thus provides an unquestionablerecord.Vice versa, after a system fault, the relaymemory can be uploaded to a PC andcomprehensive fault analysis can then takeplace in the engineer’s office.

Protection Laptop

RecordingPersonal computer

Assigning

Recording andconfirmation

System level to remote control

Substationlevel

Modem(option)

Bay level

Dataconcentrator

ERTU

Control

Coordinatedprotection & control

RTU

Relay

Fig. 14: PC-aided setting procedure

Fig. 15: Communication options

Power System Protection

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Parameter

Line data

O/C Phase settings

O/C Earth settings

Fault Recording

Breaker Fall

1000

1100

1200

1500

2800

3900

DParameter

Line data

O/C Phase settings

O/C Earth settings

Fault Recording

Breaker Fall

1000

1100

1200

1500

2800

3900

CParameter

Line data

O/C Phase settings

O/C Earth settings

Fault Recording

Breaker Fall

1000

1100

1200

1500

2800

3900

BParameter

Line data

O/C Phase settings

O/C Ground settings

Fault recording

Breaker fail

1000

1100

1200

1500

2800

3900

A

Relay data management

Analog-distribution-type relays have some20–30 setpoints. If we consider a powersystem with about 500 relays, then thenumber adds up to 10,000 settings. Thisrequired considerable expenditure in set-ting the relays and filing retrieval setpoints.A personal computer-aided man-machinedialog and archiving program assists therelay engineer in data filing and retrieval.The program files all settings systemati-cally in substation-feeder-relay order.

Corrective rather than preventivemaintenance

Numerical relays monitor their own hard-ware and software. Exhaustive self-moni-toring and failure diagnostic routines arenot restricted to the protective relay inself,but are methodically carried through fromcurrent transformer circuits to tripping re-lay coils.Equipment failures and faults in the c.t. cir-cuits are immediately reported and the pro-tective relay blocked.Thus the service personnel is now able tocorrect the failure upon occurrence, result-ing in a significantly upgraded availability ofthe protection system.

Adaptive relaying

Numerical relays now offer secure, con-venient and comprehensive matching tochanging conditions. Matching may be initi-ated either by the relay’s own intelligenceor from the outside world via contacts orserial telegrams. Modern numerical relayscontain a number of parameter sets thatcan be pretested during commissioning ofthe scheme (Fig. 17). One set is normallyoperative. Transfer to the other sets can becontrolled via binary inputs or serial datalink. There are a number of applications forwhich multiple setting groups can upgradethe scheme performance, e.g.a) for use as a voltage-dependent control

of o/c relay pick-up values to overcomealternator fault current decrement to be-low normal load current when the AVRis not in automatic operation.

b) for maintaining short operation timeswith lower fault currents, e.g. automaticchange of settings if one supply trans-former is taken out of service.

c) for “switch-onto-fault” protection to pro-vide shorter time settings when energiz-ing a circuit after maintenance.The normal settings can be restoredautomatically after a time delay.

Fig. 16: System-wide setting and relay operation library

Fig. 17: Alternate parameter groups

10 000setpoints

systemca. 500relays

200setpoints

sub

bay

20setpoints

bay

4flags

OH-Line

1200flagsp. a.

system

Relay operationsSetpoints

1

1

1

300 faults p. a.ca. 6,000 km OHL(fault rate:5 p. a. and 100 km)

d) for autoreclose programs, i.e. instanta-neous operation for first trip and delayedoperation after unsuccessful reclosure.

e) for cold load pick-up problems wherehigh starting currents may cause relayoperation.

f) for ”ring open“ or ”ring closed“ oper-ation.

Power System Protection

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Mode of operation

Numerical protection relays operate on thebasis of numerical measuring principles.The analog measured values of current andvoltage are decoupled galvanically from theplant secondary circuits via input transduc-ers (Fig. 18). After analog filtering, thesampling and the analog-to-digital conver-sion take place. The sampling rate is, de-pending on the different protection princi-ples, between 12 and 20 samples perperiod. With certain devices (e.g. generatorprotection) a continuous adjustment of thesampling rate takes place depending onthe actual system frequency.The protection principle is based on a cy-clic calculation algorithm, utilizing the sam-pled current and voltage analog measuredvalues. The fault detections determined bythis process must be established in severalsequential calculations before protectionreactions can follow.A trip command is transferred to the com-mand relay by the processor, utilizing adual channel control.The numerical protection concept offers avariety of advantages, especially with re-gard to higher security, reliability and userfriendliness, such as:

Meas. inputs

Current inputs(100 x /N, 1 s)

Voltage inputs(140 Vcontinuous)

A/Dconverter

Processorsystem

Input filter V24Serialinterface

PC interfaceLSA interface

Memory:RAMEEPROMEPROM

Input/outputports

Input/outputunits

Binaryinputs

Alarmrelay

Commandrelay

LEDdisplays0001

01010011

Amplifier

Input/output contactsdigital10 Vanalog

100 V/1 A, 5 Aanalog

O. F.

High measurement accuracy:The high ultilization of adaptive algo-rithms produce accurate results evenduring, problematic conditions

Good long-term stability:Due to the digital mode of operation,drift phenomena at components due toageing do not lead to changes in accura-cy of measurement or time delays

Security against over- and underfunctionWith this concept the danger of an unde-tected error in the device causing protec-tion failure in the case of a network faultis clearly reduced when compared to con-ventional protection technology. Cyclicaland preventive maintenance services havetherefore become largely obsolete.The integrated self-monitoring system(Fig. 19) encompasses the following areas:– Analog inputs– Microprocessor system– Command relays.

Setting of protection relays

Numerical protection devices are able tohandle a number of additional protectionrelated functions, for which additional de-vices were required in the past.

A compact numerical protection device canreplace a number of complicated conven-tional single devices.Protection functions, configurations andmarshalling data are selected by parametersetting. Functions can be activated or de-activated by configuration.By marshalling internal logic alarms (whichare produced by certain device functionson the software side) to light-emittingdiodes or to alarm relays, an allocationbetween these can be made (Fig. 20).The same also applies to the input con-tacts.A flexible application according to thespecific requirements of the plant configu-ration is possible thanks to the extensivemarshalling and configuration options.All set values are stored in E2PROMS.In this way the settings cannot be lost asa result of supply failure.The setting values are accessed via 4-digitaddresses.Each parameter can be accessed and al-tered via the integrated operator panel oran externally connected operator terminal.

Fig. 18: Block diagram of numerical protection

Power System Protection

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The display appears on an alphanumericLCD display with 2 lines with 16 charactersper line. A code word prevents uninten-tional changes of setting values.Some relays allow for the storage of4 different sets of protection settings. Viabinary inputs or via the operator panel aparticular set of setting values can be acti-vated (switching of settings groups).

Fault analysis

The evaluation of faults is simplified by nu-merical protection technology. In the eventof a fault in the network, all events as wellas the analog traces of the measured volt-ages and currents are recorded.The following types of memory are avail-able: 1 operational event memory

Alarms that are not directly assigned toa fault in the network (e.g. monitoringalarms, alternation of a set value, block-ing of the automatic reclose function).

3 fault-event historiesAlarms that occurred during the last3 faults on the network (e.g. type offault detection, trip commands, fault lo-cation, autoreclose commands). A re-close cycle with one or more reclosuresis treated as one fault history. Each newfault in the network overrides the oldestfault history.

A memory for the fault recordings forvoltage and current. Up to 8 fault record-ings are stored. The fault recordingmemory is organized as a ring buffer, i.e.a new fault entry overrides the oldestfault record.

1 earth-fault event memory (optional forisolated or resonant grounded networks)Event record of the sensitive earth faultdetector (e.g. faulted phase, real compo-nent of residual current).

The time tag attached to the fault-recordevents is a relative time from fault detec-tion with a resolution of 1 ms. In the caseof devices with integrated, battery back-upclock the operational events as well as thefault detection are assigned the internalclock time and date stamp.The memory for operational events andfault record events is protected against fail-ure of auxiliary supply with battery back-upsupply.The integrated operator interface or a PCsupported by the programming tool DIGSIis used to retrieve fault reports as well asfor the input of settings and marshalling.

Plausibility check of input quantitiese.g. iL1 + iL2 + iL3 = iE

uL1 + uL2 + uL3 = uE

Check of analog-to-digital conversionby comparison withconverted reference quantities

A

D

Hardware and software monitoring ofthe microprocessor system incl. memory,e.g. by watchdog and

cyclic memory checks

Micro-processorsystem

Monitoring of the tripping relaysoperated via dual channels

Relay

Tripping check or test reclosure by localor remote operation (not automatic)

Logical signal

LED1

LED2

LED3

LED4

LED5

LED6

LED7

. . .LED No.

Start L1

Start L2

Start L3

Start E

Trip

Autoreclosure

.

.

.

Power System Protection

Fig. 20: Marshalling matrix, LED control as an example

Fig. 19: Self-monitoring system

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A further source of information is the indi-cation via LEDs and alarm relays, as wasthe case with traditional relays. The LEDscan be selected on an individual basis toprovide the indication stored or unstored,depending on what information they repre-sent. In the case of devices with internalbattery back-up, the LED indications arerestored following an auxiliary power sup-ply failure. The alarm relays in these de-vices provide N0-type contacts, some ofthem changeover contacts.

Operation of numerical protectiondevices

The DIGSI operation software enables con-venient and transparent operation of thenumerical protection devices using a PC.The new DIGSI V3 version operates underWINDOWS and can therefore make useof all advantages of this internationally ac-cepted user interface.DIGSI V3 uses protocol-secured data ex-change between PC and protection device.This data exchange also meets the stand-ard recommendations for the interface be-tween protection equipment and stationcontrol equipment (IEC 870-5-103).

Application

DIGSI V3 is a WINDOWS PC program,with which numeric protection relays canbe conveniently operated under menuguidance using the serial interface of a PC(see Fig. 21). The PC can thus be directlyconnected with the protection device via aV24 (RS232) interface cable. The isolatedconnection version using optoelectricalconverter and fiber-optic cable is recom-mended, particularly if the protection de-vice is in operation in the substation.

Hardware and software platform

PC 386 SX or above, with at least4 Mbytes RAM

DIGSI V3 requires about 10 Mbytesharddisk space

Additional hard-disk space per installedprotection device 2 to 3 Mbytes

One free serial interface to the protec-tion device (COM 1 to COM 4)

One floppy disk drive 3.5", high densitywith 1.44 Mbytes (required for installa-tion)

MS DOS 5.0 or higher WINDOWS version 3.1 or higher

Power System Protection

Fig. 21: Operation of the protection relays using PC and DIGSI V3 software program

Fig. 22: Parameterization using DIGSI V3

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Power System Protection

Operation features

The DIGSI V3 user interface is structuredin accordance with the SAA/CUA standardused for WINDOWS programs (see Fig. 22).The selection of a system, a feeder and aprotection device is implemented in DIGSIV3, using system, bay and protection unitaddresses. Consistent use of this principle,which will be supported in future both inprotection devices and DIGSI file manage-ment, prevents incorrect allocation of pro-tection units within a system.DIGSI V3 supports the complete parame-terization and marshalling functionality ofthe numeric Siemens protection relays.Parameterization and routing of a protec-tion device can be done in file mode.All advanced storage media for manage-ment and archiving of this data (e.g. mem-ory cards, exchangeable hard disks, opto-disks, etc.) are provided. Device files of aprotection unit created in the office can betransferred subsequently with protocol-security into the protection unit. Data con-sistency is ensured, for example, by auto-matic comparison of data stored on a fileand in the device.DIGSI V3 permits the readout of operation-al and fault events from a protection de-vice which are stored with a 1 millisecondrealtime resolution. This enables effectiveand rapid fault analysis, which contributesto optimization of protection in networkoperation. Archiving and printout are con-veniently supported. The polling procedureis defined as a standard.Likewise, measured load values of a pro-tection device can be read out on-line andrecorded. Integration of extensive testfunctions facilitate the PC-guided commis-sioning and testing of a protection device.

Printer, plotter, networks

DIGSI V3 uses the full WINDOWS inter-face functionality. All common printers andplotters for which WINDOWS drivers areavailable can be used with DIGSI V3. Theuser is therefore not faced with any restric-tions when purchasing printers or plottersas long as WINDOWS drivers are available.Even transmission of information via faxfrom DIGSI V3 can be implemented.Linking into the PC network and remoteaccess to DIGSI V3 via communication net-works (e.g. ISDN) are part of the frame-work as supported by the WINDOWS op-erating system.

Evaluation of the fault recording

Readout of the fault record from the pro-tection device by DIGSI V3 is done byfault-proof scanning procedures in accord-ance with the standard recommendationfor transmission of fault records.A fault record can also be read out repeat-edly. In addition to analog values, such asvoltage and current, binary tracks can alsobe transferred and presented.DIGSI V3 is supplied together with theDIGRA (Digsi Graphic) program, whichprovides the customer with full graphicaloperating and evaluation functionality likethat of the digital fault recorders (Oscil-lostores) from Siemens (see Fig. 23).Real-time presentation of analog distur-bance records, overlaying and zooming ofcurves, visualization of binary tracks (e.g.trip command, reclose command, etc.) arealso part of the extensive graphical func-tionality as are setting of measurementcursors, spectrum analysis and R/X deriva-tion.

Fig. 23: Display and evaluation of a fault record using DIGSI V3

Data security, data interfaces

DIGSI V3 is a closed system as far as pro-tection parameter security is concerned.The security of the stored data of the oper-ating PC is ensured by checksums. Thismeans that it is only possible to changedata with DIGSI V3, which subsequentlycalculates a checksum for the changeddata and stores it with the data. Changesin the data and thus in safety-related pro-tection data are thus reliably detected.DIGSI V3 is, however, also an open sys-tem. The data export function supports ex-port of parameterization and marshallingdata in standard ASCII format. This permitssimple access to these data by other pro-grams, such as test programs without en-dangering the security of data within theDIGSI program system.With the import and export of fault recordsin IEEE standard format COMTRADE(ANSI) a high performance data interfaceis produced which supports import andexport of fault records into the DIGSI V3partner program DIGRA.This enables the export of fault recordsfrom Siemens protection units to custom-er-specific programs via the COMTRADEformat.

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Power System Protection

Remote relay interrogation

The numerical relay range 7**5 of Siemenscan also be operated from a remotely lo-cated PC via modem-telephone connec-tion.Up to 254 relays can be addressed viaone modem connection if the star coupler7XV53 is used as a communication node(Fig. 24).The relays are connected to the star cou-pler via optical fiber links.Every protection device which belongs toa DIGSI V3 substation structure has aunique address.The attached relays are always listening,but only the addressed one answers to theoperator command which comes from thecentral PC.If the relay which is located in a stationis to be operated from a remote office,then a device file is opened in DIGSI (V3.2or higher) and protection dialog is chosenvia modem. After password input, DIGSIestablishes a connection to the protectiondevice after receiving a call-back from thesystem.In this way secure and timesaving remotesetting and readout of data are possible.Diagnostics and control of test routines arealso possible without the need for visitingthe substation.

Housing and terminal system

The protection devices and the corre-sponding supplementary devices are avail-able mainly in 7XP20 housings (Fig. 26).The dimension drawings are to be foundon 6/24 and following pages. Installing ofthe modules in a cubicle without the hous-ing is not permissible.The width of the housing conforms to the19" system with the divisions 1/6, 1/3, 1/2or 1/1 of a 19" rack. The termination mod-ule is located at the rear of devices forpanel flush mounting or cubicle mounting(Fig. 26 left). Each termination may bemade via a screw terminal or crimp con-tact. The termination modules used eachcontain: 4 termination points for measured volt-

ages, binary inputs or relay outputs(max. 1.5 mm2) or

2 termination points for measured cur-rents (screw termination max. 4 mm,crimp contact max. 2.5 mm2) or

2 FSMA plugs for fiber-optic termination.For mounting of devices into cubicles, the8MC cubicle system is recommended. It isdescribed in Siemens Catalog NV21.

7XV53

7**57**5

7SJ60 7SJ60 7SJ60

RS485 Bus

opt.

RS485

DIGSI V3

DIGSI V3PC, remotely located

Modem

Office

Substation

AnalogISDN

Modem,optionally withcall-back function

Star coupler

Signal converter

PC,centrally locatedin the substation(option)

Fig. 24: Remote relay communication

The standard cubicle has the followingdimensions:2200 mm x 900 mm x 600 mm (HxWxD).These cubicles are provided with a 44 Uhigh mounting rack (standard height unitU = 44.45 mm). It can swivel as much as180° in a swing frame.The rack provides for a mounting width of19", allowing, for example, 2 devices witha width of 1/2 x 19" to be mounted. Thedevices in the 7XP20 housing are securedto rails by screws. Module racks are notrequired.To withdraw crimp contact terminations,the following tool is recommended:extraction tool No. 135900 (from Messrs.Weidmüller, Paderbornstrasse 157,D-32760 Detmold).In the housing version for surface mount-ing, the terminations are wired up on ter-minal strips on the top and bottom side ofthe device (max. terminated wire crosssection 7 mm2). For this purpose two-tierterminal blocks are used to attain the re-quired number of terminals (Fig. 26 right).

According to IEC 529 the degree of protec-tion is indicated by the identifying IP, fol-lowed by a number for the degree of pro-tection. The first digit indicates theprotection against accidental contact andingress of solid foreign bodies, the seconddigit indicates the protection against water.7XP20 housings are protected against ac-cess to dangerous parts with a wire, dustand dripping water (IP 51).

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Power System Protection

Fig. 25: Numerical protection relays in 7XP20 standard housings

Fig. 26 left: Connection method for panel flash mounting including fiber-optic interfaces; right: Connection method for panel surface mounting

1/6 1/3 1/2 1/1 of 19" width

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ANSINo.*

14

21

21N

24

25

27

27/59/81

32

32F

32R

37

40

46

47

48

49

49R

49S

50

50N

51G

Aut

orec

lose

+Sy

nchr

oche

ckSy

nchr

oniz

ing

Bre

aker

failu

re

Volta

ge, F

requ

ency

7VE5

1

7SV5

12

* ANSI/IEEE C 37.2: IEEE Standard Electrical Power System Device Function Numbers

7RW

600

7SJ6

07S

J511

7SJ5

127S

J55

7SJ5

31

7SJ5

517S

J60

Ove

rcur

rent

Mot

or p

rote

ctio

n

Diff

eren

tial

7VH

807U

T512

7UT5

137S

S50/

517V

H83

7UM

511

7UM

512

7UM

515

7UM

516

7VK5

12

Gen

erat

or p

rote

ctio

n

7SA

511

7SA

513

7SD

247S

D50

27S

D50

37S

D51

17S

D51

2Fi

ber-

optic

cur

rent

com

pari

son

Description

Protection functions

Zero speed and underspeed dev.

Distance protection, phase

Distance protection, ground

Overfluxing

Synchronism check

Synchronizing

Undervoltage

U/f protection

Directional power

Forward power

Reverse power

Undercurrent or underpower

Field failure

Load unbalance, negative phasesequence overcurrent

Phase sequence voltage

Incomplete sequence, lockedrotor, failure to accelerate

Thermal overload

Rotor thermal protection

Stator thermal protection

Instantaneous overcurrent

Instantaneous ground faultovercurrent

Ground overcurrent relay

Pilo

t wir

e di

ffere

ntia

l

Dis

tanc

e

–– – – – – – – – – –––– – – – – –

Type

Relay Selection Guide

Power System Protection

Fig. 27a

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Power System Protection

Fig. 27b

Aut

orec

lose

+Sy

nchr

oche

ckSy

nchr

oniz

ing

Bre

aker

failu

re

Volta

ge, F

requ

ency

7VE5

1

7SV5

12

* ANSI/IEEE C 37.2: IEEE Standard Electrical Power System Device Function Numbers

7RW

600

7SJ6

07S

J511

7SJ5

127S

J55

7SJ5

31

7SJ5

517S

J60

Ove

rcur

rent

Mot

or p

rote

ctio

n

Diff

eren

tial

7VH

807U

T512

7UT5

137S

S50/

517V

H83

7UM

511

7UM

512

7UM

515

7UM

516

7VK5

12

Gen

erat

or p

rote

ctio

n

7SA

511

7SA

513

7SD

247S

D50

27S

D50

37S

D51

17S

D51

2Fi

ber-

optic

cur

rent

com

pari

son

ANSINo.*

Pilo

t wir

e di

ffere

ntia

l

Dis

tanc

e

Stator ground-fault overcurrent

Overcurrent with time delay

Ground-fault overcurrentwith time delay

Overvoltage

Residual voltage ground-faultprotection

Rotor ground fault

Directional overcurrent

Directional ground-faultovercurrent

Stator ground-fault, directionalovercurrent

Out-of-step protection

Autoreclose

Frequency relay

Carrier interface

Lockout relay, start inhibit

Differential protection, generator

Differential protection, transf.

Differential protection, bus-bar

Differential protection, motor

Differential protection, line

Restricted earth-fault protection

Voltage and power directional rel.

Breaker failure

51GN

51

51N59

59N

64R

67

67N

67G

68/78

79

81

85

86

87G

87T

87B

87M

87L

87N

92

BF

Description

Protection functions

Type

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Siemens Power Engineering Guide · Transmission & Distribution6/20

21

21N

67N

79

25

85

68

78

49

50 50N

51N51

49

46

50 50N

51N51

BF

67

67N

79

51N

48

79

*

**

* only with 7SJ512

47

Power System Protection

Protection relays

Siemens manufactures a complete seriesof numerical relays for all kinds of protec-tion application.The series is briefly portrayed on the fol-lowing pages.

7SJ60

Universal overcurrentand overload protection

Phase-segregated measurement andindication (Input 3 ph, IE calculated)

All instantaneous, i.d.m.t. and d.t.characteristics can be set individuallyfor phase and ground faults

Selectable setting groups Integral autoreclose function (option) Thermal overload, unbalanced load

and locked rotor protection Suitable for busbar protection with

reverse interlocking With load monitoring, event and fault

memory

7SJ511

Universal overcurrent protection

Phase-segregated measurement andindication (3 ph and E)

I.d.m.t and d.t. characteristics can be setindividually for phase and ground faults

Suitable for busbar protection withreverse interlocking

With integral breaker failureprotection

With load monitoring, event and faultmemory

7SJ512

Digital overcurrent-time protectionwith additional functions

the same features as 7SJ511, plus: Autoreclose Sensitive directional ground-fault protec-

tion for isolated, resonant or high-resist-ance grounded networks

Directional module when used asdirectional overcurrent relay (optional)

Selectable setting groups Inrush stabilization

7SA511

Subtransmission line protectionwith distance-to-fault locator

Universal distance relay for all networks,with many additional functions, amongstothers Universal carrier interface (permissive

and blocking procedures programmable) Power swing blocking or tripping Selectable setting groups Sensitive directional ground-fault deter-

mination for isolated and compensatednetworks

Ground-fault protection for earthed net-works

Single and three-pole autoreclose Synchrocheck Free marshalling of optocoupler inputs

and relay outputs Line load monitoring, event and fault

recording Thermal overload protection

Fig. 28: 7SJ60 Fig. 29: 7SJ511/512

Fig. 30: 7SA511

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21 25

5921N

67N

85

87L

49

6051

BF 79

79BF

68

87L

49

5051

BF

78

Power System Protection

7SA513

Transmission line protectionwith distance-to-fault locator

Fast distance protection, with operatingtimes less than one cycle (20 ms at50 Hz), with a package of extra functionswhich cover all the demands of extra-high-voltage applications

Universal carrier interface (permissiveand blocking procedures programmable)

Power swing blocking or tripping Parallel line compensation Load compensation that ensures high

accuracy even for high-resistance faultsand double-end infeed

High-resistance ground-fault protection Back-up ground-fault protection Overvoltage protection Single- and three-pole autoreclose Synchrocheck option Breaker failure protection Free marshalling of a comprehensive

range of optocoupler inputs and relayoutputs

Selectable setting groups Line load monitoring, event and fault

recording High-performance measurement using

digital signal processors Flash EPROM memories

7SD511

Current-comparison protectionfor overhead lines and cables

With phase-segregated measurement For serial data transmission

(19.2 kbits/sec)– with integrated optical transmitter/

receiver for direct fiber-optic link upto approx. 15 km distance

– or with the additional digital signaltransmission device 7VR5012 up to150 km fiber-optic length

– or through a 64 kbit/s channel of avail-able multipurpose PCM devices, viafiber-optic or microwave link

Integral overload and breaker failureprotection

Emergency operation as overcurrentback-up protection on failure of data link

Automatic measurement and correctionof signal transmission time, i.e. channel-swapping is permissible

Line load monitoring, event and faultrecording

Fig. 31: 7SA513

Fig. 32: 7SD511 Fig. 33: 7SD512

7SD512

Current-comparison protectionfor overhead lines and cables

with functions as 7SD511, but additionallywith autoreclose function for single- andthree-pole fast and delayed autoreclosure.

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87 T 49 50/51

87BB BF

87T

49

87REF50G

50/51

**

* 87REF or 50G

Power System Protection

7UT512

Differential protection for machinesand power transformers

with additional functions, such as: Numerical matching to transformer ratio

and connection group (no matchingtransformers necessary)

Thermal overload protection Back-up overcurrent protection Measured-value indication for com-

missioning (no separate instrumentsnecessary)

Load monitor, event and fault recording

7UT513

Differential protectionfor three-winding transformers

with the same functions as 7UT512, plus: Sensitive restricted ground-fault

protection Sensitive d.t. or i.d.m.t. ground-fault –

o/c-protection

7SS5

Numerical busbar protection

With absolutely secure 2-out-of-2 meas-urement and additional check zone, eachprocessed on separate microprocessorhardware

With fast operating time (< 15 ms) Extreme stability against c.t. saturation Completely self-monitoring, including c.t.

circuits, isolator positions and run time With integrated circuit-breaker failure

protection With commissioning-friendly aids (indica-

tion of all feeder, operating and stabiliz-ing currents)

With event and fault recording Designed for single and multiple bus-

bars, up to 8 busbar sections and 32 bays

7UM511/12/15/16

Multifunctional devicesfor machine protection

With 10 protection functions on average,with flexible combination to completeprotection systems from the smallest tothe largest motor generator units

With improved measurement methodsbased on Fourier filters and the evalua-tion of symmetrical components (fullynumeric, frequency compensated)

With load monitoring, event and faultrecording

Fig. 34: 7UT512 Fig. 35: 7UT513

Fig. 36: 7SS5

Fig. 37: Protection operation with the PC operatorprogram DIGSI

See separate reference list for machineprotection.Order No. E50001-U321-A39-X-7600

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51

64

67N

87L

49

27

37

46

49R

50

46

51N

BF

49LR

37

51N

59

50G 86

48

49

51

51G

50

51

27

50 7950N 49 59

Power System Protection

7VE51

Paralleling device

for synchronization of generators andnetworks Absolutely secure against faulty switch-

ing due to duplicate measurement withdifferent procedures

With numerical measurand filtering thatensures exact synchronization even innetworks suffering transients

With synchrocheck option Available in two versions: 7VE511 with-

out, 7VE512 with voltage and frequencybalancing

Combined bay protection and controlunit 7SJ531

Line protection

Non directional time overcurrent Directional time overcurrent IEC/ANSI and user definable TOC curves Overload protection Sensitive directional ground fault Negative sequence overcurrent Under/Overvoltage Breaker failure Autoreclosure Fault locator

Motor protection

Thermal overload Locked rotor Start inhibit Undercurrent

Control functions

Measured-value acquisition Signal and command indications P, Q, cos ϕ and meter-reading calculation Measured-value recording Event logging Switching statistics Feeder control diagram with load indica-

tion Switchgear interlocking

7SJ551

Universal motor protectionand overcurrent relay

Thermal overload protection– separate thermal replica for stator

and rotor based on true RMS currentmeasurement

– up to 2 heating time constants for thestator thermal replica

– separate cooling time constants forstator and rotor thermal replica

– ambient temperature biasing of ther-mal replica

Connection of up to 8 RTD sensors Multi-curve overcurrent and ground-fault

protection:– four selectable i.d.m.t. and d.t. curves

for phase faults, two for ground-faults– customized curves instead of standard

curves can be programmed to offeroptimal flexibility for both phase andground elements

Real-Time Clock: last 3 events are storedwith real-time stamps of alarm and tripdata

7SD502

Pilot-wire differential protection forlines and cables (2 pilot wires)

Up to about 25 km telephone-type pilotlength

With integrated overcurrent back-upand overload protection

Also applicable to 3-terminal lines(2 devices at each end)

Fig. 38: 7SJ531 Fig. 39: 7SJ551

Fig. 40: 7SD502/503

7SD503

Pilot-wire differential protection for linesand cables (3 pilot wires)

Up to about 15 km pilot length With integrated overcurrent back-up

and overload protection Also applicable to 3-terminal lines

(2 devices at each end)

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Front view

Case 7XP2030-2 for relays 7SD511, 7SJ511/12, 7SJ531, 7UT512, 7VE51

145

150

17230 29.5

266244

231.5

1.5

10

Opticalfibreinterface

131.57.310513.2 5.4

ø 5or

M4 255.8

146

245

ø 6

Side view Panel cutout

225

220 17230 29.5

266

1,5

231.5

10

Optical fiber interface180

ø 5or

M4

206.513.67.3

245 255.8

221

ø 6

5.4

Front view

Case 7XP2040-2 for relays 7SA511, 7UT513, 7SD512, 7UM5**, 7VE512, 7SD502/503

Side view Panel cutout

56.5±0.370

75

Back view

244266

Side view

Case 7XP20 for relays 7SJ600, 7RW600

37 172 29.5

245 +1 255 ±0.3

71+2

ø 5or

M4

7.3

ø 6

Panel cutout

Fig. 41

Fig. 42

Fig. 43

Power System Protection

All dimensions in mm.

Cutout and drilling dimensions

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7XR9672 Core-balance current transformer (zero sequence c.t.)

14

K

102

200

120

2

55

120

14.5 x 6.5 K

L

k l96 104

M6

7XR9600 Core-balance current transformer (zero sequence c.t.)

170

143

81

94

8012

Diam.6.4

54

Diam.149

Fig. 44

Fig. 45

Power System Protection

Fig. 46

70172 29.530

26624

75

Case 7XP2020-2

3056.3

13.27.3

ø 5or

M4

5.4

71

ø 6

255.8245

Front view Side view Back view Panel cutout

All dimensions in mm.

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Siemens Power Engineering Guide · Transmission & Distribution6/26

Case for relay 7SJ551

105 17230

266

29.5

115

244 255.9

86.4100

Front view Side view Back view

Case 7XP2060-2 for relay 7SA513

266

445

450

13.2

7.3

245

405

431.5

5.4

255.8

446

ø 6

ø 5 or M4

2661.5

10

30 172 29.5

Front view

Optical fiberinterface

Side view

Panel cutout

Power System Protection

Fig. 47

Fig. 48

All dimensions in mm.

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Siemens Power Engineering Guide · Transmission & Distribution 6/27

Typical protection schemes

Power System Protection

Fig. 49

from both ends6

5

4

3

2

1

10

9

8

7

11

13

12

17

16

15

14

20

19

18

Circuitnumber

Radial feeder circuit

Ring main circuit

Distribution feeder with reclosers

Parallel feeder circuit

Cable or short overhead line with infeedfrom both ends

Overhead lines or longer cables with infeed

Cables andoverhead lines

Applicationgroup

Circuit equipmentprotected

Transformers Small transformer infeed

Large or important transformer infeed

Dual infeed with single transformer

Parallel incoming transformer feeder

Parallel incoming transformer feeder with bus tie

Motors Small- and medium-sized motors

Large HV motors

Generators Smallest generator < 500 kW

Small generator, around 1 MW

Large generator > 1 MW

Generator-transformer unit

Busbars Busbar protection by o/c relays withreverse interlocking

High-impedance differential busbar protection

Low-impedance differential busbar protection

6/28

6/28

6/29

6/29

6/30

6/30

Page

6/31

6/31

6/32

6/32

6/33

6/33

6/34

6/34

6/35

6/35

6/36

6/37

6/38

6/38

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Power System Protection

1. Radial feeder circuit

Notes:

1) Autoreclosure 79 only with O.H. lines.2) Negative sequence o/c protection 46 as

sensitive back-up protection against un-symmetrical faults.

General hints:

– The relay at the far end (D) gets theshortest operating time.Relays further upstream have to betime-graded against the next down-stream relay in steps of about 0.3 sec-onds.

– Inverse-time curves can be selected ac-cording to the following criteria:

– Definite time:source impedance large compared tothe line impedance, i.e. small currentvariation between near and far endfaults

– Inverse time:Longer lines, where the fault current ismuch less at the end of the line than atthe local end.

– Very or extremely inverse time:Lines, where the line impedance is largecompared to the source impedance(high difference for close-in and remotefaults), or lines, where coordination withfuses or reclosers is necessary.Steeper characteristics provide alsohigher stability on service restoration(cold load pick-up and transformer inrush currents)

2. Ring main circuit

General hints:

– Operating time of overcurrent relays tobe coordinated with downstream fusesof load transformers.(Preferably very inverse time characteris-tic with about 0.2 s grading-time delay

– Thermal overload protection for thecables (option)

– Negative sequence o/c protection 46 assensitive protection against unsymmetri-cal faults (option)

51N51 46 79

51N51 46

51N51 46

Infeed

Furtherfeeders

I>, t IE>, t I2>, t ARC

2) 1)

I>, t IE>, t I2>, t

A

B

C

Load

Load Load

D I>, t IE>, t I2>, t

7SJ60

7SJ60

7SJ60

Transformerprotection,see Fig. 56

51N51 46 49

I>, t IE>, t I2>, t52

5252

51N51 46 49

I>, t IE>, t I2>, t ϑ>52

Infeed

7SJ60

Transformerprotection,see Fig. 56

7SJ60

ϑ>

Fig. 50

Fig. 51

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Siemens Power Engineering Guide · Transmission & Distribution 6/29

Power System Protection

3. Distribution feeder withreclosers

General hints:

– The feeder relay operating characteris-tics, delay times and autoreclosurecycles must be carefully coordinatedwith downstream reclosers, sectionaliz-ers and fuses.The instantaneous zone 50/50N is nor-mally set to reach out to the first mainfeeder sectionalizing point. It shall en-sure fast clearing of close-in faults andprevent blowing of fuses in this area(“fuse saving”). Fast autoreclosure isiniciated in this case.Further time delayed tripping and reclo-sure steps (normally 2 or 3) have to begraded against the recloser.

– The o/c relay should automaticallyswitch over to less sensitive characteris-tics after longer breaker interruptiontimes to enable overriding of subse-quent cold load pick-up and transformerinrush currents.

52

50/51

50N/51N

46

79

52

7SJ60

Infeed

I>>,I>, t

IE>>,IE>, t

I2>, t

Auto-reclose

Recloser

Sectionalizers

Fuses

Furtherfeeders

52

51N51 49 46 7SJ60

7SJ51267N67 51 51N

52

52

52

52

52

52

52

52

Infeed

Protectionsame asline or cable 1

I>, t IE>, t I2>, tϑ>

Load

O.H. line orcable 1

O.H. line orcable 2

Load

Fig. 52

Fig. 53

4. Parallel feeder circuit

General hints:

– This circuit is preferably used for theinterruptionfree supply of important con-sumers without significant back-feed.

– The directional o/c protection 67/67Ntrips instantaneously for faults on theprotected line. This allows the savingof one time-grading interval for the o/c-relays at the infeed.

– The o/c relay functions 51/51N haveeach to be time-graded against theupstream located relays.

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5. Cables or short overhead lines withinfeed from both sides

Notes:

1) Autoreclosure only with overhead lines2) Overload protection only with cables3) Differential protection options:

– Type 7SD511/12 with direct fiber-opticconnection up to about 20 km or via a64 kbit/s channel of a general purposePCM connection (optical fiber, micro-wave)

– Type 7SD502 with 2-wire pilot cablesup to about 20 km

– Type 7SD503 with 3-wire pilot cablesup to about 10 km.

2)

3)

2)

3)

1)

7SA511

52

52

52

85 79

52

52

52

52

52 52 52 52

21/21N

79

67N

67N21/21N

85

7SA511

Load

Infeed

Sameprotectionfor parallel line,if applicable

Line orcable

Backfeed

7SD5**

5252

52

51N/51N 87L

79

49

1)

2)

52

51N/51N

87L

79

49

1)

2)7SD5**

3)

52

52

52

52 52 52 52

Load

Infeed

Sameprotectionfor parallel line,if applicable

Line orcable

Backfeed

7SJ60

7SJ60

Power System Protection

Fig. 54

Fig. 55

6. Overhead lines or longer cables withinfeed from both sides

Notes:

1) Teleprotection logic 85 for transfer tripor blocking schemes. Signal transmis-sion via pilot wire, power-line carrier,microwave or optical fiber (to be pro-vided seperately). The teleprotectionsupplement is only necessary if fastfault clearance on 100% line length isrequired, i.e. second zone tripping(about 0.3 s delay) cannot be acceptedfor far end faults.

2) Directional ground-fault protection 67Nwith inverse-time delay against high-resistance faults

3) Single- or multishot autoreclosure 79only with overhead lines.

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7. Small transformer infeed

General hints:

– Ground-faults on the secondary side aredetected by current relay 51G which,however, has to be time graded againstdownstream feeder protection relays.The restricted ground-fault relay 87N canoptionally be provided to achieve fastclearance of ground-faults in the trans-former secondary winding.Relay 7VH80 is high-impedance typeand requires class X c.t.s with equaltransformation ratio.

– Primary breaker and relay may be re-placed by fuses.

5150 51N 49 46 7SJ60

52

52

7UT513

51G 7SJ60

87N

51N51

87T

52

52

63

I>> I>, t IE> ϑ> I2>, t

Load

HV infeed High voltage, e.g. 115 kV

2)

1)

I>, t IE>, t

7SJ60

Load

Load bus, e.g. 13.8 kV

Power System Protection

Fig. 56

Fig. 57

8. Large or important transformerinfeed

Notes:

1) Three winding transformer relaytype 7UT513 may be replaced by two-winding type 7UT512 plus high-imped-ance-type restricted ground-fault relay7VH80. However, class X c.t. coreswould additionally be necessary in thiscase. (See small transformer protection)

2) 51G may additionally be provided,in particular for the protection of theneutral resistance, if provided.

3) Relays 7UT512/513 provide numericalratio and vector group adaption.Matching transformers as used withtraditional relays are therefore no moreapplicable.

5150 50N 49

7SJ60

52

52

46

63

87N

51G

7SJ60

RN

52

HV infeed

I>> I>, t IE> ϑ>

Load

Optional resistor orreactor

I2>, t

I>>

IE>7VH80

o/c-relay

Distribution bus

Fuse

Load

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9. Dual-infeed with single transformer

Notes:

1) Line c.t.s are to be connected to sepa-rate stabilizing inputs of the differentialrelay 87T in order to guarantee stabilityin case of line through-fault currents.

2) Relay 7UT513 provides numerical ratioand vector group adaption. Matchingtransformers, as used with traditionalrelays, are therefore no longer applica-ble.

52 52

46

51 51N50

49

63

7SJ60

7SJ60

52

52 52 52

7UT51387T87N

Protection line 1same as line 2

Load

I>> IE>

Protection line 221/21N or 87L + 51 + optionally 67/67N

I>> I>, t IE>, t

ϑ>I2>

7SJ60

Loadbus

51G

51N51

Power System Protection

Fig. 58

Fig. 59

10. Parallel incoming transformerfeeders

Note:

1) The directional functions 67 and 67Ndo not apply for cases where the trans-formers are equipped with transformerdifferential relays 87T.

5150 51N 49 46

52

52

51G

52

52

52 52

63

51N51

52

67 67N

I>, t IE>, t IE>

7SJ512

I>> I>, t IE>, t ϑ> I2>, t

Load

HV infeed 1

7SJ60

Load

HV infeed 27SJ60

Protection

same asinfeed 1

I>

1)

Load

Loadbus

IE>, t

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Siemens Power Engineering Guide · Transmission & Distribution 6/33

49CR

52

4951N50 7SJ60

49CR

52

50 7SJ531 or7SJ551

51G 67G

M

M

Lockedrotor

I>> Lockedrotor

IE> ϑ>

46

I>>

IE>

ϑ> I2>

4649

I<

37

2)7XR961)60/1A

I2>

11. Parallel incoming transformerfeeders with bus tie

Note:

1) Overcurrent relays 51, 51N each con-nected as a partial differential scheme.This provides a simple and fast busbarprotection and saves one time-gradingstep.

5150 51N 49 46

52

52

51G

51 51N

52

52

5151N

52

I>> I>, t IE>, t ϑ> I2>, t

Load

Infeed 1

7SJ60

Load

I>, t IE>, t I>, tIE>, t

7SJ60 7SJ60

Infeed 27SJ60

Protectionsame asinfeed 1

Power System Protection

Fig. 60

Fig. 61b

Fig. 61a

12. Small- and medium-sized motors< about 1 MW

a) With effective or low-resistancegrounded infeed (IE ≥ I N Motor)

General hint:

– Applicable to low-voltage motors andhigh-voltage motors with low-resistancegrounded infeed (IE ≥ IN Motor).

b) With high-resistance grounded infeed(IE ≤ IN Motor)

Notes:

1) Window-type zero sequence c.t.2) Sensitive directional ground-fault protec-

tion 67N only applicable with infeedfrom isolated or Peterson-coil groundednetwork.

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13. Large HV motors > about 1 MW

Notes:

1) Window-type zero sequence c.t.2) Sensitive directional ground-fault protec-

tion 67N only applicable with infeedfrom isolated or Peterson-coil groundednetwork.

3) This function is only needed for motorswhere the run-up time is longer than thesafe stall time tE.

According to IEC 79-7, the tE-time is thetime needed to heat up a.c. windings,when carrying the starting current IA,from the temperature reached in ratedservice and at maximum ambient tem-perature to the limiting temperature.A separate speed switch is used tosupervise actual starting of the motor.The motor breaker is tripped if the motordoes not reach speed in the preset time.The speed switch is part of the motordelivery itself.

4) Pt100, Ni100, Ni1205) 49T only available with relay type 75J551

49CR

52

50

7UT512

51G 67G

7SJ531 or7SJ551

49T

Speedswitch M

87M

37

Lockedrotor

I>>

IE>

ϑ> I2>

4649

U<

27

2)7XR961)60/1A

Start-upsuper-visior

I< Optional

RTD's 4)optional

3)

3)

Power System Protection

7SJ60G

46 495151N

I>, IE>, t

LV

I2> ϑ>

G146 4951

51N7SJ60

RN =VN

√3 • (0.5 to 1) • Irated

I>, IE>, t I2> ϑ>

MV

Generator 2

Fig. 62

Fig. 63b: With resistance grounded neutral

14. Smallest generators < 500 kW

Fig. 63a: With solidly grounded neutral

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Siemens Power Engineering Guide · Transmission & Distribution 6/35

52

7UM511

G

51

51G

64R

PI>, t

IE>, t

I2>

4632

L.O.F

40

1)

Field

15. Small generator, typically 1 MW

Note:

1) Two c.t.s in V-connection also sufficient.

Power System Protection

52

7UM511

G

51G

64R

P

87

87G

51

27

81

59

51 32 46 40 49

7SJ60

MV

I

RE Field<

I>, t

2)

IG

O/Cv.c.

I2> L.O.F. ϑ>

1)

1)

U<

U>

f>

IE>, t

Field

3)

Fig. 64

Fig. 65

16. Large generator > 1 MW

Notes:

1) Functions 81 und 59 only requiredwhere prime mover can assume excessspeed and voltage regulator may permitrise of output voltage above upper limit.

2) Differential relaying options:– 7UT512: Low-impedance differential

protection 87– 7UT513: Low-impedance differen-

tial 87 with integral restricted ground-fault protection 87G

– 7VH83: High-impedance differentialprotection 87 (requires class X c.t.s)

3) 7SJ60 used as voltage-controlled o/cprotection.Function 27 of 7UM511 is used toswitch over to a second, more sensitivesetting group.

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87U

87TU

Unittrans.

63

71 Oil low

Transf. fault press

51TN

Transf. neut. OC

Unit diff.51

Unit aux.back-up

78

40

32

59Over volt

Loss ofsync.

Loss offield

Over freq.

Volt/Hz

51TN

Unitaux.

Trans.diff.

87T

Trans.neut.OC

81N

24

49S

87G

StatorO.L.

Gen.diff.

G

2146

Neg.seq.

Sys.back-up

59GN

Gen.neut. OV

51GN

64R64R2

E

Fieldgrd.

Fieldgrd.

63

71Transf.fault press

Oil low

Reversepower

2)

1)

52

A

Power System Protection

17. Generator-transformer unit

Notes:

1) 100% stator ground-fault protectionbased on 20 Hz voltage injection

2) Sensitive field ground-fault protectionbased on 1 Hz voltage injection

3) Only used functions shown, furtherintegrated functions available in each re-lay type (see ”Relay Selection Guide“,Fig. 27).

Fig. 66

46 59 81N 49 64R40

32 21 7859GN

51GN

64R2

241) 2)

87G and optionally

87U

5151N

87T2

optionally3

87TU

7UM511

7UM516

7UM515

7UT512

7UT513

7SJ60

Relaytype

Functions 3) Numberof relaysrequired

1

1

1

1

3

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Siemens Power Engineering Guide · Transmission & Distribution 6/37

Power System Protection

18. Busbar protection by O/C relayswith reverse interlocking

General hint:

Applicable to distribution busbars withoutsubstantial (< 0.25 x IN) backfeed from theoutgoing feeders

Fig. 67

52

52

5050N

5151N

52

5050N

5151N

5050N

5151N

52

5050N

5151N

7SJ60

7SJ60

7SJ60 7SJ60

t0 = 50 ms

I> I>, t I> I>, t

I>, t0 I>, t

I> I>, t

Infeed

reverse interlocking

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Power System Protection

19. High impedance busbarprotection

General hints:

– Normally used with single busbarand 1 1/2 breaker schemes

– Requires separate class X current trans-former cores. All c.t.s must have thesame transformation ratio

Fig. 68

87BB

87S.V.

5151N

Transformerprotection

7VH83

52 52

G

Feederprotection

Feederprotection

52

G

Feederprotection

86Alarm

Load

Fig. 69

20. Low-impedance busbar protection

General hints:

– Preferably used for multiple busbarschemes where an isolator replica isnecessary

– The numerical busbar protection 7SS5provides additional breaker failure pro-tection

– C.t. transformation ratios can be differ-ent, e.g. 600/1 A in the feeders and2000/1 at the bus tie

– The protection system and the isolatorreplica is continuously self-monitored bythe 7SS5

– Feeder protection can be connected tothe same c.t. core.

5050N

Back-feed

7SS5

52

Infeed

Transformer protecton

52 52

Feederprotection

52

Bus tieprotection

BF

86

87BB

Load

Feederprotection

Isolatorreplica

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Siemens Power Engineering Guide · Transmission & Distribution 6/39

Nominal power[MVA]

Time constant[s]

0.5 . . . 1.0

0.16 . . . 0.2

1.0 . . . 10

0.2 . . . 1.2

>10

1.2 . . . 720

Rated transformer power [MVA]

Time constant of inrush current

12.0

11.0

10.0

9.0

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

102 100 400

Peak value of inrush current

IRush^

IN^

Power System Protection

Protection coordination

Relay operating characteristics and theirsetting must be carefully coordinated inorder to achieve selectivity. The aim is ba-sically to switch-off only the faulted com-ponent and to leave the rest of the powersystem in service in order to minimize sup-ply interruptions and to guarantee stability.

Sensivity

Protection should be as sensitive as possi-ble to detect faults at the lowest possiblecurrent level.At the same time, however, it shouldremain stable under all permissible load,overload and through-fault conditions.

Phase-fault relays

The pick-up values of phase o/c relays arenormally set 30% above the maximumload current, provided that sufficient short-circuit current is available.This practice is recommmended in particu-lar for mechanical relays with reset ratiosof 0.8 to 0.85.Numerical relays have high reset ratiosnear 0.95 and allow therefore about 10%lower setting.Feeders with high transformer and/ormotor load require special consideration.

Transformer feeders

The energizing of transformers causesinrush currents that may last for seconds,depending on their size (Fig. 70).Selection of the pick-up current and as-signed time delay have to be coordinatedso that the rush current decreases belowthe relay o/c reset value before the setoperating time has elapsed.The rush current typically contains onlyabout 50% fundamental frequency compo-nent.Numerical relays that filter out harmonicsand the DC component of the rush currentcan therefore be set more sensitive. Theinrush-current peak values of Fig. 70 willbe nearly reduced to one half in this case.

Ground-fault relays

Residual-current relays enable a muchmore sensitive setting, as load currents donot have to be considered (except 4-wirecircuits with single-phase load). In solidlyand low-resistance grounded systems asetting of 10 to 20% rated load current isgenerally applied.

High-resistance grounding requires muchmore sensitive setting in the order ofsome amperes primary.The ground-fault current of motors andgenerators, for example, should be limitedto values below 10 A in order to avoid ironburning.Residual-current relays in the star pointconnection of c.t.s can in this case not beused, in particular with rated c.t. primarycurrents higher than 200 A. The pick-upvalue of the zero-sequence relay wouldin this case be in the order of the errorcurrents of the c.t.s.A special zero-sequence c.t. is thereforeused in this case as earth current sensor.The window type current transformer7XR96 is designed for a ratio of 60/1 A.The detection of 6 A primary would thenrequire a relay pick-up setting of 0.1 Asecondary.

An even more sensitive setting is appliedin isolated or Peterson-coil grounded net-works where very low earth currents occurwith single-phase-to-ground faults.Settings of 20 mA and less may then berequired depending on the minimumground-fault current.Sensitive directional ground-fault relays(integrated in the relays 7SJ512, 7SJ55and 7SA511) allow settings as low a 5 mA.

Fig. 70: Transformer inrush currents, typical data

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Power System Protection

Differential relays (87)

Transformer differential relays are normallyset to pick-up values between 20 and 30%rated current. The higher value has to bechosen when the transformer is fitted witha tap changer.Restricted ground-fault relays and high-re-sistance motor/generator differential relaysare, as a rule, set to about 10% ratedcurrent.

Instantaneous o/c protection (50)

This is typically applied on the final supplyload or on any protective device with suffi-cient circuit impedance between itself andthe next downstream protective device.The setting at transformers, for example,must be chosen about 20 to 30% higherthan the maximum through-fault current.

Motor feeders

The energizing of motors causes a startingcurrent of initially 5 to 6 times rated cur-rent (locked rotor current).A typical time-current curve for an induc-tion motor is shown in Fig. 71.In the first 100 ms, a fast decaying assy-metrical inrush current appears additionally.With conventional relays it was currentpractice to set the instantaneous o/c stepfor short circuit protection 20 to 30%above the locked-rotor current with a shorttime delay of 50 to 100 ms to override theasymetrical inrush periode.Numerical relays are able to filter out theasymmetrical current component very fastso that the setting of an additional timedelay is no longer applicable.The overload protection characteristicshould follow the thermal motor character-istic as closely as possible. The adaption isto be made by setting of the pick-up valueand the thermal time constant, using thedata supplied by the motor manufacturer.Further, the locked-rotor protection timerhas to be set according to the characteris-tic motor value.

Time grading of o/c relays (51)

The selectivity of overcurrent protectionis based on time grading of the relay oper-ating characteristics. The relay closer tothe infeed (upstream relay) is time-delayedagainst the relay further away from the in-feed (downstream relay).This is shown in Fig. 73 by the example ofdefinite time o/c relays.The overshoot times takes into accountthe fact that the measuring relay continuesto operate due to its inertia, even whenthe fault current is interrupted. This may

Fig. 71: Typical motor current-time characteristics

be is high for mechanical relays (about0.1 s) and neglectable for numerical relays(20 ms).

Inverse time relays (51)

For the time grading of inverse-time relays,the same rules apply in principle as for thedefinite time relays. The time grading isfirst calculated for the maximum fault leveland then checked for lower current levels(Fig. 72).

If the same characteristic is used for allrelays, or when the upstream relay hasa steeper characteristic (e.g. very overnormal inverse), then selectivity is auto-matically fulfilled at lower currents.

0 1 2 3 4 5 6 7 8 9

Time in seconds

10

High set instantaneous o/c step

Motor thermal limit curve

Permissible locked rotor time

Motor starting current

Locked rotor current

Overload protection characteristic

10000

1000

100

10

1

.1

.01

.001

Current in multplies of full-load amps

Time

0.2–0.4 seconds

51

5151

Maximum feeder fault levelCurrent

Main

Feeder

Fig. 72: Coordination of inverse-time relays

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Power System Protection

* also called overtravel orcoasting time

Example 1

tTG = 0.10 + 0.15 + 0.15 = 0.40 s

Example 2

Mechanical relays: tOS = 0.15 sOil circuit breaker t52F = 0.10 sSafety margin for measuring errors,etc.: tM = 0.15

Numerical relays: tOS = 0.02 sVacuum breaker: t52F = 0.08 sSafety margin: tM = 0.10 s

tTG = 0.08 + 0.02 + 0.10 = 0.20 s

t51M– t51F = t52F + tOS + tM

Time grading tTG

52M

52F 52F

Operating time

0.2–0.4Time grading

51

5151

M

FF

Interruption offault current

Faultdetection

Faultinception

Circuit-breaker

Set time delay Interruption time

Overshoot*

Margin tM

t51M

t51F t52FI>

I>tOS

Fig. 73: Time grading of overcurrent-time relays

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Calculation example

The feeder configuration of Fig. 74 and theassigned load and short-circuit currents aregiven.Numerical o/c relays 7SJ60 with normalinverse-time characteristic are applied.The relay operating times dependent oncurrent can be taken from the diagram orderived from the formula given in Fig. 75.The IP /IN settings shown in Fig. 74 havebeen chosen to get pick-up values safelyabove maximum load current.This current setting shall be lowest forthe relay farthest downstream. The relaysfurther upstream shall each have equal orhigher current setting.The time multiplier settings can now becalculated as follows:

Station C:

For coordination with the fuses, weconsider the fault in location F1.The short-circuit current related to13.8 kV is 523 A.This results in 7.47 for I /IP at the o/crelay in location C.

With this value and TP = 0.05we derive from Fig. 75an operating time of tA = 0.17 s

This setting was selected for the o/c relayto get a safe grading time over the fuse onthe transformer low-voltage side.The setting values for the relay at station Care therefore: Current tap: IP /IN = 0.7 Time multipler: TP = 0.05

Station B:

The relay in B has a back-up function forthe relay in C.The maximum through-fault current of1.395 A becomes effective for a fault inlocation F2.For the relay in C, we obtain an operatingtime of 0.11 s (I /IP = 19.9).We assume that no special requirementsfor short operating times exist and cantherefore choose an average time gradinginterval of 0.3 s. The operating time of therelay in B can then be calculated: tB = 0.11 + 0.3 = 0.41 s Value of IP /IN = 1395 A = 6.34

(see Fig. 74). 220 A With the operating time 0.41 s

and IP/IN = 6.34,we can now derive TP = 0.11from Fig. 75.

Power System Protection

Fig. 74

The setting values for the relay at station Bare herewith Current tap: IP /IN = 1.1 Time multiplier TP = 0.11Given these settings, we can also checkthe operating time of the relay in B for aclose-in fault in F3:The short-circuit current increases in thiscase to 2690 A (see Fig. 74). The corre-sponding I/IP value is 12.23. With this value and the set value of

TP = 0.11we obtain again derive from Fig. 75an operating time of 0.3 s.

Station A:

We add the time grading interval of0.3 s and find the desired operating timetA = 0.3 + 0.3 = 0.6 s.

Following the same procedure as for therelay in station B we obtain the followingvalues for the relay in station A: Current tap: IP /IN = 1.0 Time multiplier: TP = 0.17 For the close-in fault at location F4 we

obtain an operating time of 0.48 s.

Fig. 75: Normal inverse time characteristic ofrelay 7SJ60

Example: Time grading of inverse-time relays for a radial feeder

– – – – –

*) Iscc.max. = Maximum short-circuit current** Ip/IN = Relay current multiplier setting*** Iprim = Primary setting current corresponding to Ip/IN

A

B

C

D

Station

300

170

50

Max. Load[A]

I scc. max.*[A]

4500

2690

1395

523

400/5

200/5

100/5

I p/I N **CT ratio I prim***[A]

1.0

1.1

0.7

400

220

70

11.25

12.23

19.93

Fuse:160 A

515151

A F4 F3 F2

13.8 kVLoad

L.V.

7SJ607SJ607SJ60

I /I p =I scc. max.

I prim

F1

Load

Load

B C D13.8 kV/0.4 kV

1.0 MVA5.0%

I/Ip [A]

Tp [s]

Normal inverse

.

3.2

1.6

0.8

0.4

0.2

0.1

0.05

t [s]

1

2

345

10

20

304050

100

0.14

(I/Ip)0.02 – 1Tp [s]t =

82 10 20640.05

0.1

0.2

0.30.40.50

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Power System Protection

I A>,t

I C>,t

I B>,t

t [s

]

t [m

in]

210 5

2

5

.01

.001

2

5

.1

2

5

1

2

5

10

2

5

100

2100 5 21000 5

I max

= 4

500

A

I scc

= 2

690

A

I scc

= 1

395

A

I –

0.4

kVm

ax=

16.

000

kA

fuse 13.8/0.4 KV1.0 MVA5.0%

VDE 160

Bus-C

Bus-B

7SJ600

7SJ600

7SJ600

Ip = 0.10 – 4.00 xInTp = 0.05 – 3.2 sI>>= 0.1 – 25. xIn

Ip = 1.0 xInTp = 0.17 sI>>= ∞

Ip = 0.10 – 4.00 xInTp = 0.05 – 3.2 sI>>= 0.1 – 25. xIn

Ip = 1.1 xInTp = 0.11 sI>>= ∞

Ip = 0.10 – 4.00 xInTp = 0.05 – 3.2 sI>>= 0.1 – 25. xIn

Ip = 0.7 xInTp = 0.05 sI>>= ∞

IN

400/5 A

200/5 A

100/5 A

A

TR

fuse

I [A]

10 4

2 51000 10 4 10 52 5 2

13.80 kV 0.40 kV

1

HRC fuse 160 A

Setting range Setting

I>>I>, t

I>>I>, t

I>>I>, t

52

52

52

The normal way

To prove the selectivity over the wholerange of possible short-circuit currents, it isnormal practice to draw the set operatingcurves in a common diagram with doublelog scales. These diagrams can be manual-ly calculated and drawn point by point orconstructed by using templates.Today computer programs are also availa-ble for this purpose. Fig. 76 shows the re-lay coordination diagram for the exampleselected, as calculated by the Siemensprogram CUSS (computer-aided protectivegrading).

Fig. 76: O/c time grading diagram

Note:

To simplify calculations, only inverse-timecharacteristics have been used for this ex-ample. About 0.1 s shorter operating timescould have been reached for high-currentfaults by additionally applying the instanta-neous zones I>> of the 7SJ60 relays.

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Power System Protection

Coordination of o/c relays with fusesand low-voltage trip devices

The procedure is similar to the above de-scribed grading of o/c relays. Usually atime interval between 0.1 and 0.2 secondsis sufficient for a safe time coordination.Very and extremely inverse characteristicsare often more suitable than normal in-verse curves in this case. Fig. 77 showstypical examples.Simple consumer-utility interrupts use apower fuse on the primary side of the sup-ply transformers (Fig. 77a).In this case, the operating characteristic ofthe o/c relay at the infeed has to be coordi-nated with the fuse curve.Very inverse characteristics may be usedwith expulsion-type fuses (fuse cutouts)while extremly inverse versions adapt bet-ter to current limiting fuses.In any case, the final decision should bemade by plotting the curves in the log-logcoordination diagram.Electronic trip devices of LV breakers havelong-delay, short-delay and instantaneouszones.Numerical o/c relays with one inverse timeand two definite-time zones can be closelyadapted (Fig. 77b).

Fig. 77: Coordination of an o/c relay with an MV fuse and a low-voltage breaker trip device

Time

Current

Time

Current

0.2 seconds

Maximum fault level at MV bus

Secondarybreaker

o/c relay

0.2 seconds

Maximum fault available at HV bus

Fuse

Inverse relay

I>>

I2>, t2

I1>, t1

a)

b)

LV bus

MV

an

51

Fuse

MV bus

an

5051

LV bus

otherconsumers

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XPrimary Minimum =

= XRelay Min xVTratio

CTratio

[Ohm]

Imin =XPrim.Min

X’Line [Ohm/km]

[Ohm][km]

Power System Protection

Coordination of distance relays

The reach setting of distance times musttake into account the limited relay accuracyincluding transient overreach (5% accord-ing to IEC 255-6), the c.t. error (1% forclass 5P and 3% for class 10P) and a secu-rity margin of about 5%. Further, the lineparameters are normally only calculated,not measured. This is a further source oferrors.A setting of 80–85% is therefore commonpractice: being 80% used for mechanicalrelays while 85% can be used for themore accurate numerical relays.

Fig. 78: Grading of distance zones

Fig. 79: Operating characteristic of Siemens distance relays 7SA511 and 7SA513

Where measured line or cable impedancesare available, the reach setting may also beextended to 90%. The second and thirdzones have to keep a safety margin ofabout 15 to 20% to the correspondingzones of the following lines. The shortestfollowing line has always to be considered(Fig. 78).As a general rule, the second zone shouldat least reach 20% over the next station toensure back-up for busbar faults, and thethird zone should cover the largest follow-ing line as back-up for the line protection.

Grading of zone times

The first zone normally operates unde-layed. For the grading of the time intervalsof the second and third zones, the samerules as for o/c relays apply (see Fig. 73).For the quadrilateral characteristics (relays7SA511 and 7SA513) only the reactancevalues ( X values) have to be consideredfor the reach setting. The setting of theR values should cover the line resistanceand possible arc or fault resistances. Thearc resistance can be roughly estimatedas follows:

X1A

X2A

X3A

R3AR2AR1A

X

RA

B

C

D

Typical settings of the ratio R/X are:– Short lines and cables (≤ 10 km):

R/X = 2 to 10– Medium line lengths < 25 km: R/X = 2– Longer lines 25 to 50 km: R/X = 1

Shortest feeder protectable bydistance relays

The shortest feeder that can be protectedby underreach distance zones without theneed for signaling links depends on theshortest settable relay reactance.

IArc = arc length in mIscc Min = minimum short-circuit current

Iscc Min

RArc =IArc x 2kV/m

Fig. 80

Fig. 81

B

t1

ZLA-B~

t2

t3Z3A

A C DZLB-C ZLC-D

Z2A

Z1A

Z2B

Z1B Z1C

Load LoadLoad

Z1A = 0.85 • ZLA-B

Z2A = 0.85 • (ZLA-B+Z1B)

Z3A = 0.85 • (ZLA-B+Z2B)

Operatingtime

The shortest setting of the numericalSiemens relays is 0.05 ohms for 1 Arelays, corresponding to 0.01 ohms for5 A relays.This allows distance protection of distribu-tion cables down to the range of some500 meters.

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Local and Remote Control

Introduction

State-of-the-art

Modern protection and substation controluses microprocessor technology and serialcommunication to upgrade substation op-eration, to enhance reliability and to reduceoverall life cycle cost.The traditional conglomeration of often to-tally different devices such as relays, me-ters, switchboards and RTUs are replacedby a few multifunctional, intelligent devicesof uniform design. And, instead of exten-sive parallel wiring, only a few serial linksare used (Fig. 82 and 83).Control of the substation takes place withmenu-guided procedures at a central VDUwork place.

Fig. 82

F F

Traditional protection and substation control

Remote terminal unit

To network control center

Alarm annunciationand local control

Marshalling rack

Approx. 20 to40 cores per bay

Mimic displayPushbuttonsPosition indicatorsInterposing relaysLocal/remote switch

Control

Indication lampsMeasuring instrumentsTransducersTerminal blocksMiniature circuit breakers

Monitoring

e.g.Overcurrent relaysGround-fault relaysReclosing relaysAuxiliary relays

Protection

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Local and Remote Control

Fig. 83

* The compact central control unit can be located in a separate cubicle ordirectly in the low-voltage compartment of the switchgear

** Protection relays are serially connected to the control I/O units

Coordinated protection and substation control system LSA 678

Keyboard

Printer (option)

VDU

System control center

Compact centralcontrol unitincluding RTU functions

shown withopen door

**

Protectionrelay

ControlI/O unit

Low-voltage compartmentof the medium-voltageswitchgear

2 fiber-optic coresper feeder

Protectionrelay

ControlI/O unit

*

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Local and Remote Control

Technical proceedings

The first coordinated protection and sub-station control system LSA 678 was com-missioned in 1986 and continuously furtherdeveloped in the following years. It nowfeatures the following main characteristics: Coordinated system structure Optical communication network

(star configuration) High processing power

(32-bit MP technology) Standardized serial interfaces and com-

munication protocols Uniform design of all components Complete range of protection and con-

trol functions Comprehensive user-software support

packages.Currently (1996) over 400 systems are insuccessful operation at all voltage levelsup to 400 kV.

System structureand scope of functions

The LSA system performs supervisorylocal control, switchgear interlocking, bayand station protection, synchronizing,transformer tap-changer control, switchingsequence programs, event and fault re-cording, telecontrol, etc.It consists of the independent subsystems(Fig. 84): Supervisory control 6MB51/52 Protection 7S**5Normally, switchgear interlocking is inte-grated as software program in the supervi-sory control system. Local bay control isimplemented in the bay-dedicated I/O con-trol units.For complex substations with multiplebusbars, however, these functions areoften provided as an independent back-upsystem: Interlocking and local control 8TKCommunication and data exchange be-tween components is performed via serialdata links. Optical-fiber connections arepreferred to ensure EMI compatibility.The cummunication structure of the con-trol system is designed as a hierarchicalstar configuration. It operates in the pollingprocedure with a fixed assignment of themaster function to the central unit. Thedata transmission mode is asynchronous,half-duplex, protected with a hammingdistance d = 4, and complies with theIEC Standard 870-5.Each subsystem can operate fully in stand-alone mode even in the event of loss ofcommunication.

Fig. 84: Distributed structure of coordinated protection and control LSA

Data sharing between protection and con-trol via the so-called informative interfaceaccording to IEC 870-5-103 is restricted tononcritical measuring or event recordingfunctions. The protection units, for exam-ple, deliver RMS values of currents, voltag-es, power, instantaneous values for oscillo-graphic fault recording and time-taggedoperating events for fault reporting.Besides the high data transmission securi-ty, the system also provides self-monitor-ing of individual components.The distributed structure also makes theLSA system attractive for refurbishmentprograms or extensions, where conven-tional secondary equipment has to be inte-grated.It is general practice to provide protectionof HV and EHV substations as separate,self-contained relays that can communi-cate with the control system, but functionotherwise completely independently.At lower voltage levels, however, higherintegrated solutions are accepted for costreasons.For distribution-type substations combinedprotection and control feeder units (e.g.7SJ531) are available which integrate allnecessary functions of one feeder, includ-ing: local feeder control, overcurrent andoverload protection, breaker-failure protec-tion and metering.

Supervisory control

The substation is monitored and controlledfrom the operator‘s desk (Fig. 84). TheVDU shows overview diagrams and com-plete details of the switchgear on a colordisplay. Current/actual measurands can becalled up on request. All event and alarmannunciations are selectable in form oflists. The control procedure is menu-guidedand uses either a mouse, or an easy tohandle keyboard with a minimum numberof function and cursor keys. The operationis therefore extremely user-friendly anddoes not require special training of the op-erating staff.

Automatic functions

Apart from the provided switchgear inter-locking, a series of automatic functionsensure an effective and secure systemoperation.Automatic switching sequences, such aschanging of busbars, can be user-pro-grammed and started locally or remotely.Furthermore, two important automationfunctions have been integrated into thesystem software and are available asoptions: synchronizing and transformertap-changer control.

VDU

System control center

Supervisory control system 6 MB

”Master unit“Stationlevel

Time signal

Interlockingsystem 8TK

Protection 7SSupervisory controlsystem 6 MB

”Bay unit“ ”Bay protection“”I/O unit“

Switchyard

Baylevel

8TKmasterunit

1…

ParallelSerial

…n

LSAPROCESSOperator’s

desk

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Local and Remote Control

Fig. 85: Digital substation control, operator desk. Control of a 400 kV substation (double control unit)

Both functions run on the relevant baylevel units, controlled by the central masterunit. The performance of these functionscorresponds to modern digital stand-aloneunits. The advantages of the integratedsolution, however, are: External auxiliary relay circuits for the

selection of measurands are no longerapplicable.

Adaptive parameter setting becomespossible from local or remote controllevels.

High processing powerThe processing power of the central con-trol unit has been enormously increasedby the introduction of the 32-bit MP tech-nology. This permits, on the one hand, amore compact design and provides, on theother hand, sufficient processing reservefor the future introduction of additionalfunctions.

Static memoriesA decisive step in direction of user friend-liness has been made with the implemen-tation of large nonvolatile Flash EPROMmemories. The system parameters can beloaded via a serial port at the front panel ofthe central unit. Bay level parameters areautomatically downloaded.A change of EPROM hardware is no longernecessary when parameters have to bechanged or added for the implementationof new functions or the extension of sub-stations.

Analog value processingThe further processing of raw measureddata, such as the calculation of maximum,minimum or effective values, with as-signed real time is contained as standardfunction.A Flash EPROM mass storage canoptionally be provided to record measuredvalues, fault events or fault oscillograms.The stored information can be read outlocally or remotely by a telephone modemconnection. Further data evaluation(harmonic analysis, etc.) is then possibleby means of a special PC program (LSAPROCESS).

Compact designA real reduction in space and cost hasbeen achieved by the creation of compactI/O and central units. The processing hard-ware is enclosed in metallic cases withEMI-proof terminals and optical serial inter-faces. All units are type tested accordingto the latest IEC standards.In this way, the complete control and pro-tection equipment can be directly integrat-ed into the MV or HV switchgear(Fig. 86, 87).

Switchgear interlockingand local control

In simple distribution stations, the inter-locking can be part of the control software.For larger stations with a multiple busbarlayout, in particular on the EVH level,an independent, digital interlocking system(8TK) with integrated local control ele-ments is applied in many cases.It ensures fail-safe switching and person-nel safety down to the lowest control lev-el, i.e. directly at the switch panel, evenwhen supervisory control is not available.The interlocking system consists of distrib-uted, feeder-dedicated MP units and onecentral unit which is normally assigned tothe bus-coupler bay. The information ex-change is performed via serial links in theswitchyard.The front panel of each unit contains con-trol elements with switch position indica-tors for local (site) control. This system hasalso been frequently applied as a stand-alone function in substations up to 800 kV.

Fig. 86: Switchgear-integrated control and protection Fig. 87: View of a low-voltage compartment

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Local and Remote Control

Numerical protection

A complete range of fully digital (numeri-cal) relays is available (see chapter PowerSystem Protection 6/8 and following pag-es).They all have a uniform design compatiblewith the control units (Fig. 88). This appliesto the hardware as well as to the softwarestructure and the operating procedures.Metallic standard cases, IEC 255-tested,with EMI-secure terminals, ensure an un-complicated application comparable to me-chanical relays. The LCD display and set-ting keypad are integrated. Additionally aRS232 port is provided on the front panelfor the connection of a PC as an MMI.The rear terminal block contains an optical-fiber interface for the data communicationwith the LSA control system.The relays are normally linked directly tothe relevant I/O control unit at the baylevel. Connection to the central controlsystem unit is, however, also possible.The numerical relays are multifunctionaland contain, for example, all the necessaryprotection functions for a line feeder ortransformer. At higher voltage levels, addi-tional, main or back-up relays are applied.The new relay generation has extendedmemory capacity for fault recording (5 sec-onds, 1 ms resolution) and nonvolatilememory for important fault informations.The serial link between protection and con-trol uses standard protocols in accordancewith IEC 870-5-103.In this way, supplier compatibility andinterchangeability of protection devices isachieved.

Communication with control centres

The LSA system uses protocols that com-ply with IEC Standard 870-5. In many cas-es an adaption to existing proprietary pro-tocols is necessary, when the systemcontrol center has been supplied by anoth-er manufacturer.For this purpose, a larger number of proto-col converters have been developed andan extensive protocol library now exists.Further protocol converters can be provid-ed on demand.By adding software that runs on the com-munication processor of the ERTU, thedifferent protocol converters can be imple-mented.

Fig. 89: Enhanced remote terminal unit 6MB55, application options

Fig. 88: Numerical protection, standard design

Enhanced remote terminal units

For substations with existing remoteterminal units, an enhancement towardsthe LSA performance level is feasible.The telecontrol system 6MB55, basedupon LSA components, replaces outdatedremote terminal units (Fig. 89).Conventional RTUs are connected to theswitchgear via interposing relays andmeasuring transducers with a marshallingrack as a common interface.The centralized version of the LSA controlsystem (SINAUT-LSA) can be directly con-nected to this interface. The total parallelwiring can be left in its original state.In this manner, it is possible to enhancethe RTU function and to include substationmonitoring and control with the same per-formance level as the decentralized LSAsystem.Upgrading of existing substations can thusbe achieved with a minimum of cost andeffort.

VFModem

Telephone networkRemote control

VF Modem

Marshalling rackPrinter Operator

terminal

Interposing relays,transducers

Existingswitchgear Extended switchgear

ERTU

Systemcontrolcenter

Substationlevel

Bay level

Managementterminal

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Local and Remote Control

Engineering system LSATOOLS

In parallel with the upgrading of the centralunit hardware, a novel parameterizing anddocumentation system LSATOOLS hasbeen developed. It uses modern graphicalpresentation management methods,including pull-down menus and multiwin-dowing.LSATOOLS enables the complete configu-ration, parameterization and documentationof the system to be carried out on AT-com-patible PC workstations. It ensures that aconsistent database for the project is main-tained from design to commissioning(Fig. 90).The system parameters, generated byLSATOOLS, can be serially loaded intothe Flash EPROM memory of the centralcontrol unit and will then be automaticallydownloaded to the bay level devices(Fig. 91).Care has been taken to ensure that chang-es and expansions are possible withoutrequiring a complete retest of the system.Supplier independent system modificationsand extensions are therefore possible.

Fig. 90: Engineering system LSATOOLS

Fig. 91: PC-aided parameterization of LSA 678 with LSATOOLS and downloading of parameters

Parameterizing Documentation

Single-linediagram

Circuitdiagram

Deviceconfiguration

Parameters Function,processingdiagram

PC input

Engineering system

CAD systemSIGRAPH-ET

Downloading of parametersduring startup

LSATOOLSparameterization station

Documentation

Loading ofparameters

Network control center

Master unit

PC inputs

Input/output units

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Substation control system6MB51/52

In the 6MB51/52 substation control sys-tem the functions are distributed betweenstation and bay control levels.The input/output devices have thefollowing tasks on the bay control level: Signal acquisition Acquisition of measured and count

values Monitoring the execution of master

control unit commands, e.g. for– Control of switchgear– Transformer step changing– Setting of Peterson coilsData processing, such as– Limit monitoring of measured values,

including initiation of responses tolimit violations

– Calculation of derived operationalmeasured values (e.g. P, Q, cos ϕ )and/or operational parameters(for example r.m.s. values, slave point-er) from the logged instantaneous val-ues for current and voltage

– Deciding how much information totransmit to the control master unit ineach polling cycle

– Generation of group signals andderiving of signals internally,e.g. from self-monitoring

Switchgear-related automation tasks– Switching sequences in response to

switching commands or to processevents

– Transformer control– Synchronization

Transmission of data from numerical pro-tection relays to the control master unit

Local display of status and measuredvalues.

Bay control units

A complete range of devices is available tomeet the particular demands concerningprocess signal/capacity and functionality(see Fig. 98). All units are built-up in mod-ern 7XP20 housings and can be directlyinstalled in the low-voltage compartmentsof the switchgear or in separate cubicles.The smallest device 6MB525 is designedas a low-cost version and contains onlycontrol functions. It is provided with anRS485-wired serial interface and is normal-ly used for simple distribution-typesubstations together with overcurrent/over-load relays 7SJ60 and digital measuringtransducers 7KG60. (see application exam-ple, Fig. 118).

Fig. 92: LSA 678 protection and substation control system with the 6MB substation control system

Local and Remote Control

All further bay control devices contain anoptic serial interface for connection to thecentral control unit, and an RS232 serialinterface on the front side for connectionof an operating PC. Further, integral dis-plays for measuring values and LEDs forstatus indication are provided.

Minicompact device 6MB525

It contains signal inputs and command out-puts for substation control. Analog measur-ing inputs, where needed, have to be pro-vided by additional measuring transducers,type 7KG60. Alternatively, the measuringfunctions of the numerical protection re-lays can be used. These can also providelocal indication of measuring values.The local bay control is intended to beperformed by the existing, switchgear inte-grated mechanical control.

Compact devices 6MB522/523

They provide a higher number of signalinputs and outputs, and contain additionalmeasuring functions. One measuring valueor other preprocessed information can bedisplayed on the 2-row, 16-character alpha-numeric display.For local bay control an additional smallmimic board with control elements (device6MB531) can be added, or, where applica-ble, the integrated bay control panel of the8TK interlocking system can be used.

Master control unit 6MB51

Switchgear interlockmaster unit 8TK2

Station protection7SS5

Stationlevel

Serial interface

Station control centerHigher-levelcontrol system

Central evaluationstation (PC)

Telecontrol channel

Normal time

Telephone channel

1 n

Baylevel

Switchgear interlockbay unit 8TK1

1 n

Bay control unit6MB52

Protection relays7S/7U

Substation

Parallel interface

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Fig. 93: MinicompactI/O device 6MB525

Fig. 98: Standardized input/output devices with serial interfaces

Local and Remote Control

Compact devices with bay control 6MB524

This bay control device can be delivered infour versions dependent on the peripheralrequirements.It provides all control and measuring func-tions needed for switchgear bays up to theEHV level.Switching status, measuring values andalarms are indicated on a large alpha-numeric display. Measuring instrumentscan therefore be widely dispensed with.Bay control is, in this case, performed bythe additionally integrated keypad.

Combined protectionand control device 7SJ531

This fully integrated device provides all pro-tection, control and measuring functionsfor simple line/cable, motor or transformerfeeders. Protection is limited to overcur-rent, autoreclosure, overload, ground-faultand breaker-failure protection.Only one unit is needed per feeder. Space,assembly and wiring costs can thereforebe considerably reduced.Measured value display and local bay con-trol is performed in the same way as withthe bay control unit 6MB524 with a largedisplay and a keypad.

Compact*

***

Minicompact* 6MB525 2 – 6 – – – Double commands and alarmsalso as ”single“ configurable

Type Components

6MB523

6MB522-06MB522-16MB522-2

Design CommandsDouble Single

Signal inputsDouble Single

Analog inputsDirectconnectionto transformer

Connection tomeasuretransducer

1

366

122

3

366

5

51010

1 x I

2 x U, 1 x I3 x U, 3 x I4 x U, 2 x I

2–2

for simple switchgear cubicleswith one switching device

with P, Q calculation

6MB5240-0-1-2-3

468

20

1125

8121640

––––

2 x U, 1 x I3 x U, 3 x I3 x U, 3 x I9 x U, 6 x I

1225

Double commands and alarmsalso usable as ”single“

Compact withlocal (bay) controland large display

7SJ531 1 – – – 3 x U, 3 x I Double commands and alarmsalso usable as ”single“

Combined controland protectiondevice withlocal (bay) control

* Local (bay) control has to be provided separately (device 6MB531). In distribution-type substations, mechanical local control of the switchchgear is normally sufficient.

Fig. 95: Compact I/O device 6MB522Fig. 94: CompactI/O device 6MB523

Fig. 96: Compact I/O unit withlocal (bay) control 6MB5240-0

Fig. 97: Combined protection andcontrol device 7SJ531

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The 6MB51 control master unit

This unit lies at the heart of the 6MB sub-station control system and, with its 32-bit80486 processor, satisfies the most de-manding requirements.It is a compact unit inside the standardhousing used in Siemens substation sec-ondary equipment.The 6MB51 control master unit managesthe input/output devices, controls the inter-action between the control centers in thesubstation and the higher control levels,processes information for the entire stationand archives data in accordance with theparameterized requirements of the user.Specifically, the control master unit coordi-nates communication to the higher network control levels to the substation control center to an analysis center located either in

the station or connected remotely viaa telephone line using a modem

to the input/output devices and/or thenumerical protection units (bay controlunits)

to lower-level stations.This is for the purpose of controlling andmonitoring activities at the substation andnetwork control levels as well as providingdata for use by engineers.Other tasks of the control master unit are Event logging with a time resolution of

1 or 10 ms Archiving of events, variations in meas-

ured values and fault records on massstorage units

Time synchronization using radio clock(GPS, DCF77 or Rugby) or using a signalfrom a higher-level control station

Automation tasks affecting more thanone bay:– Parallel control of transformers– Synchronizing

(measured value selection)– Switching sequences– Busbar voltage simulation– Switchgear interlocking

Parameter management to meet therelevant requirements specification

Self-monitoring and system monitoring.

System monitoring primarily involves eval-uating the self-monitoring results of thedevices and serial interfaces which arecoordinated by the control master unit.In particular, important EHV substations,some users require redundancy of the con-trol master unit. In these cases, two con-trol master units are connected to eachother via a serial interface. System moni-toring then consists of mutual error recog-nition and, if necessary, automatic transferof control of the process to the redundantcontrol master unit.

The SINAUT LSA station control center

The standard equipment of the station con-trol centre includes The function keyboard with eight func-

tion keys and four cursor control keys or(alternatively) a full PC keyboard option-ally with a mouse

The PC with color monitor andLSACONTROL software package fordisplaying– A station overview– Detailed plant displays– Event and alarm lists– Alarm information

A printer for the output of reports.Various operating options are clearly dis-played in the eight menu fields on thecolor monitor. These correspond to theeight function keys.

Fig. 100: SINAUT LSA PC station control center withfunction keyboard

Local and Remote Control

The operator can access the required in-formation or initiate the desired operationquickly and safely with just a few keystrokes.The station control center can take theform of A standard PC with selectable monitor

size An industry-standard PC (e.g. built into

a switchgear cubicle top unit) or as A laptop (also portable).It can be operated at a distance from thestation.Two station control centers can be in-stalled if required by the user.

Fig. 99: Compact control master unit 6MB513 for amaximum of 32 serial interfaces to bay control units.Extended version 6MB514 for 64 serial interfaces tobay control units (double width) additionally avail-able

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Local control functions

Tasks of local control

The Siemens 6MB station control systemperforms at first all tasks for conventionallocal control: Local control of and checkback indica-

tions from the switching devices Acquisition, display and registration of

analog values Acquisition, display and registration of

alarms and fault indications in real time Metered-value acquisition and pro-

cessing Fault recording Transformer open-loop and closed-loop

control Synchronizing/parallelingUnlike the previous conventional technolo-gy with completely centralized processingof these tasks and complicated parallelwiring and marshalling of process data, thenew microprocessor-controlled technologybenefits from the distribution of tasks tothe central control master unit and the dis-tributed input/output units and of the serialdata exchange in telegrams between theseunits.

Tasks of the input/output unit

The input/output unit performs the follow-ing bay-related tasks: Fast distributed acquisition of process

data such as indications, analog valuesand switching device positions and theirpreprocessing and buffering

Command output and monitoring Assignment of the time for each event

(time tag) Isolation from the switchyard via heavy-

duty relay contacts Run-time monitoring Limit value supervision Paralleling.Analog values can be input to the bay con-trol unit both via analog value transducersand by direct connection to c.t.s and v.t.s.The required r.m.s. values for current andvoltage are digitized and calculated as wellas active and reactive power. The advan-tage is that separate measuring cores andanalog value transducers for operationalmeasurement are eliminated.

Control master unit

The process data acquired in the input/out-put unit are scanned cyclically by the con-trol master unit. The control master unitperforms further information processingof all data called from the feeders for sta-tion tasks ”local control and telecontrol“with the associated event logging and faultrecording and therefore replaces the com-plicated conventional marshalling distribu-tor racks. Marshalling is implemented un-der microprocessor control in the controlmaster unit.

Serial protection interface

All protection indications and fault record-ing data acquired for fault analysis in pro-tection relays are called by the controlmaster unit via the serial interface.These include instantaneous values forfault current and voltage of all phases andearth, sampled with a resolution of 1 ms,as well as distance-to-fault location.

Serial data exchange

The serial data exchange between the baycomponents and the control master unithas important economic advantages. Thisis especially true when one considers thepreparation and forwarding of the informa-tion via serial data link to the control centercommunication module which is a compo-nent of the control master unit. This mod-ule is a single, system-compatible micro-processor module on which both thetelecontrol tasks and telegram adaptationto telegram structures of existing remotetransmission systems are implemented.This makes the station control independentof the telecontrol technology and the asso-ciated telegram structure used in the net-work control center at a higher level of thehierarchy.

Station control center

The peripheral devices for operating andvisualization (station control center) arealso connected to the control master unit.The following devices are part of the sta-tion control center: A color VDU with a function keyboard

or mouse for display, control, event andalarm indication,

A printer for on-line logging (event list), A mass storage.

VDU with function keyboard

The display is output via the VDU. To sim-plify operation, a function keyboard is nor-mally used instead of an alphanumeric key-board with only eight function keys andfive keys for cursor positioning. Alternative-ly, operation with the mouse can be sup-plied. Handling is simplified as ”user guid-ance“ is used. Note fields in the lowerportion of the screen are assigned to eightfunction keys. These contain a text indicat-ing what is executed or selected with thekey. In this way, various detailed diagramsand lists can be selected. The contents ofthe diagrams and lists can be parameter-ized, i.e. they can be altered subsequently.

Fig. 101: Fiber-optic connectionson the control master unit

Local and Remote Control

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Switchyard overview diagram

A switchyard single-line diagram can beconfigured to show an overview of thesubstation. This diagram is used to givethe operator a quick overview of the entireswitchyard status and shows, for example,which feeders are connected or discon-nected. Current and other analog valuescan also be displayed.Information about raised or cleared opera-tional and alarm indications are also dis-played along the top edge of the screen.It is not possible to perform control actionsfrom the switchyard overview. If the opera-tor wants to switch a device, he has toselect a detailed diagram, say ”110 kVdetailed diagram“. If the appropriate func-tion key is pressed, the 110 kV detaileddiagram (Fig. 103) appears. This displayshows the switching state of all switchingdevices of the feeders.

Function field control

In the menu of the function fields, it is pos-sible, for example, to select between con-trol switching devices and tap changing.By pressing key “Control“, the yellow sig-nal of the cursor control jumps to the firstswitching device in the top left-hand cor-ner of the screen. At the same time, newfunctions are assigned to the fields alongthe bottom edge of the screen, e.g. ON orOFF. The cursor is now positioned on theswitching device to be switched.When the function key for the requiredposition of a switchig device is pressed,e.g. OFF, the switching device blinks in theswitch position to which it is to move (con-trol acknowledgement switch principle). Atthis point it is still possible to check wheth-er the selected switching command is real-ly to be executed. The actual command isoutput using another key, the ”commandoutput“ key. If the command is found tobe safe after a check has been made forviolations of interlock conditions, theswitching device in question is operated.In the case where a mouse is available,the appropriate device is selected by theusual mouse operation.Once the switching command has beenexecuted and a checkback signal has beenreceived, the blinking symbol changes tothe new actual state on the VDU.In this way, switching operations can beperformed very simply and absolutely with-out error. If commands violate the interlockconditions or if the switch position is notadopted by a switching device, for exam-ple, because of a drive fault, the relevantfault indications or notes are displayed onthe screen.

Event list

All events are logged in chronological or-der. The event list can be displayed on theVDU whenever called or printed out ona printer or stored on a mass-storage me-dium. Fig. 104 shows a section of thisevent list as it appears on the VDU.

Example event list (Fig. 104)

The date can be seen in the left-hand areaand the events are shown in order of prior-ity. Switching commands and fault indi-cations are displayed with a precision of upto 1 ms and events with high priority andprotection indications after a fault-detec-tion are shown with millisecond resolution.A command that is accepted by the controlsystem is also displayed. This can be seenby the index ”+“ of the command (OP),otherwise ”OP–“ would appear.If the switchgear device itself does notexecute the command, ”FB–“ (checkbacknegative) indicates this. ”FB+“ resultsafter successful command execution. Thetexts chosen are suggestions and can beparameterized differently.The event list shows that a protectionfault-detection (general start GS) has oc-curred with all the associated details. Thereal time is shown in the left-hand columnand the relative time with millisecond pre-cision in the right-hand column, permittingclear and fast fault analysis. The fault loca-tion, 17 km in this case, is also displayed.The lower section of the event list showsexamples of raised (RAI) and cleared (CLE)alarm indications, such as ”voltage trans-former miniature-circuit-breaker tripped“.This fault has been remedied as can beseen from the corresponding cleared indi-cation. The letter S in the top line, calledthe indication bar, indicates that a fault indi-cation has been received that is stored ina separate ”warning list“.

Example alarm list (Fig. 105)

When the alarm list is selected, it is dis-played on the VDU. In this danger alarmconcept a distinction is made betweencleared and raised and between acknowl-edged and unacknowledged indications.Raised indications are shown in red,cleared indications are green (similar tothe fast/slow blinking lamp principle).The letter Q is placed in front of an indica-tion that has not yet been acknowledged.Indications that are raised and cleared andacknowledged are displayed in white inthe list.This system with representation in thealarm list therefore supersedes dangeralarm equipment with two-frequency blink-ing lamps traditionally used with conven-tional equipment.As stated above, all events can also becontinuously logged in chronological orderon the associated printer, too. The appear-ance of this event list is identical to that onthe VDU.

Mass storage

It is also possible to store historic faultdata, i.e. fault recording data and events onmass-storage medium.It can accept data from the control masterunits and stores it on Flash EPROMs. Thisstatic memory is completely maintenance-free when compared to floppy or hard discsystems. 8Mbyte of recorded data can bestored. The locally or remotely readablememory permits evaluation of the data us-ing a PC. This personal computer can beset up separately from the control equip-ment, e.g. in an office. Communicationthen takes place via a telephone-modemconnection.In addition to fault recording data, opera-tional data, such as load-monitoring values(current, voltage, power, etc.) and eventscan be stored.

Local and Remote Control

Fig. 102: Compact I/O unit with local (bay) control, extended version 6MB5240-3

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Fig. 103: 6MB substation control, example: detailed diagram of a110 kV switchgear on the VDU

Fig. 104: 6MB substation control, example: event list on the VDU

Fig. 105: 6MB substation control, example: alarm list on the VDU Fig. 106: 6MB substation control system, example: fault recording

Local and Remote Control

Example fault recording (Fig. 106)

After a fault, the millisecond-precision val-ues for the phase currents and voltagesand the ground current and ground voltageare buffered in the feeder protection.These values are called from the numericalfeeder protection by the control masterunit and can be output as curves with theprogram OSCGRA (Fig. 106).The time marking 0 indicates the time offault detection, i.e. the relay general start(GS). Approx. 5 ms before the generalstart, a three-phase fault to ground oc-curred, which can be seen by the rise inphase currents and the ground current.12 ms after the general start, the circuitbreaker was tripped (OFF) and after further80 ms, the fault was cleared.

After approx. 120 ms the protection reset.Voltage recovery after disconnection wasrecorded up to 600 ms after the generalstart.This format permits quick and clear analy-sis of a fault. The correct operation of theprotection and the circuit breaker can beseen in the fault recording (Fig. 106).The high-voltage feeder protection present-ly includes a time range of at least 5 sec-onds for the fault recording.The important point is that this fault re-cording is possible in all feeders that areequipped with the microprocessor-control-led protection having a serial interfaceaccording to IEC 870-5-103.

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Switchgear interlocking system

Switchgear interlocking bay unit

The Siemens 8TK switchgear interlockingis used in multiple busbar switchyards withpower-operated switching devices.For each switching bay, the switchgear in-terlocking bay unit performs a combinationof local control and bay-internal interlock-ing. Fig. 108 shows the bay control unitwith integrated local control mimic pad andcontrol keys.

Switchgear interlocking central unit

A switchgear interlocking central unit isavailable for cross-bay switchyard interlock-ing. It is usually assigned to the bus tie ofthe multiple busbar system. The switch-gear interlocking central unit communicateswith the feeder units via separate shieldedfour-wire serial data lines separate fromother control components.

Serial connection of the switchgearinterlocking units

The switchgear interlocking feeder unitsare connected to the switchgear interlock-ing central unit in a star configuration viathe serial connections. The advantages ofthis star configuration are: Considerably reduced wiring for switch-

yard interlocking Higher availability Monitoring of the serial data exchange Simple expansion Self-monitoring of the switchgear inter-

locking units, the switchyard connectionand the interlock conditions.

Fig. 109 shows the equipment of a switch-yard with a switchgear interlocking centralunit and the associated switchgear inter-locking bay units.

Fig. 107: Function overview of the 8TK switchgear interlocking system

Fig. 108: Switchgear interlocking bay unit with local (bay) control and indication

Local and Remote Control

SCC bay unit SCC bay unitSCC bay unit

Interlockingmaster unit

Interlockingbay unit

Furtherbayunits

Furtherbayunits

Substation control (SSC)

Parallel wiring Serial connection

Interlockingbay unit

OF OF

Shielded cables Shielded cables

OF

Optical fibers

Switchgear

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Use and application

The switchgear interlocking system can beused both as an autonomous system andas a component of the overall coordinatedprotection and substation control system.It can therefore replace the traditional hard-wired switchgear interlocking devices usedso far with decisive added advantages.In both applications, the switchgear inter-locking system is always the back-up con-trol system in the lowest control level, i.e.in the immediate vicinity of the switchyard.This means that safe operation of theswitchyard is ensured in the event of fail-ure of a higher-level control system takingboth the bay-internal interlocking and theoverall switchgear interlocking into ac-count.Moreover, even in the event of faults inone bay, the rest of the switchyard canalso be operated subject to the switchyardinterlocking conditions and the last switch-ing device positions of the defective bay.This ensures that the device where thefault was detected does not perform mal-functions or maloperations.The defective bay can in an emergency stillbe operated authorized personnel using akeyswitch. This is even possible if thepower supply module has failed in a bay.In accordance with DIN VDE 101, Section4.4 (safe local operation) and DIN 31005(”The interlock acts by blocking or releas-ing in the event of element initiation oncondition that it is only possible to changebetween blocking and releasing if all otherelements are in their defined initial posi-tions.“), the switchgear interlocking hasbeen consistently matched to the require-ments of the switchgear. The interlocks donot have a gap anywhere and deserve thedesignation ”switchgear interlocking“.The switchgear interlocking was the firstsupplied subsystem of coordinated substa-tion control and protection. Extensive testshave been run with the switchgear inter-locking equipment both in the laboratoryand in high-voltage and extra-high-voltageswitchyards including the NEMP* test.These tests for dielectric strength andespecially for electromagnetic compatibility(EMC) have shown that the new micro-processor-controlled technology can evenbe used in the immediate vicinity of extra-high-voltage switchgears.

Fig. 109: 8TK switchgear interlocking system in a high-voltage switchyard with triple busbar system

Local and Remote Control

*Nuclear Electrical Magnetic Pulse

Q 15,25, 35

Q 10,20, 30

Q 11,21, 31

Q 1,2, 3

Q51

Q0 Q52

Q75Q7

Q 1,2, 3

Q0

Q6

Q 1,2, 3

Q0

Q9

Q7

Central unit for a maximumof 14 switching devicesfor a bus tie/bus coupler

Large bay unit for amaximum of 14 switchingdevices

Station Powersupply

Small bay unitfor a maximum of6 switching devices

Small bay unitfor a maximum of6 switching devices

Serial data-transmission line

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Application examples

The flexible use of the components of theCoordinated Protection and SubstationControl System LSA 678 is demonstratedin the following for some typical applica-tion examples.

Application in high-voltage substationswith relay kiosks

Fig. 110 shows the arrangement of thelocal components. Each two bays (line ortransformer) are assigned to one kiosk.Each bay has at least one input/output unitfor control (bay control unit) and one pro-tection unit. In extra-high-voltage, the pro-tection is normally doubled (main- andback-up protection).For important substations an independentswitchgear interlocking system is addition-ally recommended. It also provides inte-grated local (bay) control functions withcontrol switches and a small mimic padthat displays isolator and circuit breakerpositions.In this way, safe interlocked switching iseven possible when the main control sys-tem has failed.The protection relays are serially connect-ed to the bay control unit by optical-fiberlinks.

SIL(B)FPRIOU

FPRIOU

FPRIOU

FPRIOU

CSM withCCC and MS

VDU

Key:

CSMCCCMSVDU

FPRSIL(B)SIL(M)IOU

SIL(B) SIL(B) SIL(M)

Modem

Bay 1 2 n Bus coupler

Relaykiosks

To the networkcontrol center

To the operationsand maintenanceoffice

Controlbuilding

Parallel

Serial

Control system master unitControl center couplingMass storageVisual display unit

Feeder protection relaysSwitchgear interlocking bay unitSwitchgear interlocking master unitControl input/output unit

Fig. 110: Application example of outdoor HV or EHV substations with relay kiosks

Local and Remote Control

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Fig. 111: System concept with double central control

Local and Remote Control

• • • • • • • • • • • •

Control systemmaster unit 1with massstorage 1

Network control center

Control systemmaster unit 2with massstorage 2

• • • • • • • • • • • • • • • • • • • • • • • •

• • • • • • • • • •

Serial

Switchover andmonitoring*

Localcontrollevel

Printer

Control/annunciation

Controlcentercoupling

Control/annunciation

Controlcentercoupling

Baycontrol level

Protec-tion relay

Controlinput/outputunit

Switch-gearinter-locking

Protec-tion relay

Controlinput/outputunit

Switch-gearinter-locking

SwitchgearFeeder 1 Feeder n

Parallel

Printer

*only principle shown

In extremely important substations, mainlyextra-high-voltage, there exists a doublingphilosophy. In these substations, the feed-er protection, the DC supply, the operatingcoils and the telecontrol interface are dou-bled. In such cases, the station control sys-tem with its serial connections, and themaster unit with the control center cou-pling can also be doubled.Both master units are brought up-to-datein signal direction. The operation manage-ment can be switched over between thetwo master units (Fig. 111).

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Application in indoor high-voltagesubstations

The following example (Fig. 112) shows anindoor high-voltage switchgear. All decen-tralized control system components, suchas input/output unit, feeder protection andswitchgear interlocking system are alsogrouped per bay and installed close to theswitchgear. They are connected to the con-trol system master unit in the same wayas described in the outdoor version viafiber-optic cables.

Application in medium voltagesubstations

The same basic arrangement is also appli-cable to medium-voltage (distribution-type)substations (Fig. 113 and 114).The feeder protection and the compact in-put/output units are, however, preferablyinstalled in the low-voltage compartmentof the feeders (Fig. 113) to save costs.There is now a trend to apply combinedcontrol and protection units. The relay7SJ531, for example, provides protection,metering (current display) and has an inte-grated bay control with mimic and LCDpad. Thus, only one device is needed percable, motor or O.H. line feeder.

Fig. 112: Application example of indoor substations with switchgear interlocking system

Fig. 113: Protection and substation control system LSA 678 for a distribution-type substation

Key:

CSM

VDUFPR

SIL(B)SIL(M)IOU

VDU

SIL(M)FPRIOUCSM

Modem

To the net-work controlcenter

To the office

Parallel Serial

Control system master with controlcenter coupling and mass storageMonitorFeeder protection relays

Switchgear interlocking bay unitSwitchgear interlocking master unitControl input/output unit

Control room Switchgear room

SIL(B)

FPR

IOU

FPR

IOU

Controlandpro-tectioncubicles

Switchgear Buscoupler

SIL(B)

bay 1 bay 2 …

Network controlcenter

Operation place

Feeder protection unit(e.g. 7UT51 transformer protection)

Feeder I/O contol unit (e.g. 6MB524)

Combined control andprotection feeder unit 7SJ531

Miniature I/O unit 6MB525

Feeder protection(e.g. 7SD5 line differential protection)

1

2

3

45

Control systemmaster unit withoptical-fiber link

VDU with keyboard Printer

1 2 3 4 5

Protection and substation control LSA 678 with input/output units and numerical protectioninstalled in low-voltage compartments of the switchgear

Local and Remote Control

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Fig. 114: Application example of medium-voltage switchgear

Fig. 115: Principle wiring diagram of the medium-voltage feeder components

To the office

Parallel Serial

Key:

VDU

To the network control center

Buscoupler

IOU FPR IOU FPR CSM IOU FPR

Control system masterwith mass storage andcontrol center couplingMonitor

Feeder protectionrelayInput/output unit

For o/c feeder ormotor protection alsoas one combinedunit (7SJ531) available

Control room Switchgear room

Switchgear

CSM

VDU

FPR

IOU

Modem

Fig. 115 shows an example for the mostsimple wiring of the feeder units.The voltages between the input/output unitand the protection can be paralleled at theinput/output unit because the plug-in mod-ules have a double connection facility.The current is connected in series be-tween the devices. The current input atthe input/output unit is dimensioned for100xIN, 1 s (protection dimensioning).The plug-in modules have a short-circuitingfacility to avoid opening of c.t. circuits.The accuracy of the operational measure-ments depends on the protection charac-teristics. Normally, it is approx. 2% of IN.If more exact values are required, a sepa-rate measuring core must be provided.The serial interface of the protection isconnected to the input/output unit.The protection data is transferred to thecontrol master unit via the connection be-tween the input/output unit and the masterunit. Thus, only one serial connection to themaster unit is required per feeder.

Local and Remote Control

Control I/0 unit 1) Numerical 1)

For o/c feeder protection or motor protectionalso as combined controland protection unit 7SJ531 available

Switching status

6MB52 ProtectionPlug-in module

c.b. ON/OFF 2)

Short-circuitingfacility

Protectioncore

U

I

2)closeoropen

2)closeortrip

1)

2) Only one circuit shown

Serial data connection

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System configuration

The system arrangement depends on thetype of substation, the number of feedersand the required control and protectionfunctions. The basic equipment can bechosen according to the following criteria:

Central control master unithas to be chosen according to thenumber of bay control units to be seriallyconnected: 6MB513 for a maximum of 32 serial

interfaces 6MB514 for a maximum of 64 serial

interfacesAt the most 9 more serial interfaces areavailable for connection of data channels toload despach centers, local substation con-trol PCs, printers, etc.

Substation control centerIt normally consists of a PC with a specialcontrol keyboard or normal keyboard witha mouse, color monitor, LSA CONTROLsoftware and a printer for the output ofreports.For exact time synchronization of 1 milli-second accuracy, a GPS or DCF77 receiverwith antenna may be used.

Bay control unitsNormally, a separate bay control unit is as-signed to every substation bay. The typehas to be selected according to the follow-ing requirements: Number of command outputs

that means the sum of circuit breakers,isolators and other equipment to be cen-trally or remotely controlled. The stateddouble commands are normally providedfor double-pole (”+“ and ”–“) control oftrip or closing coils.Each double-pole command can be sep-arated into two single-pole commandswhere stated (Fig. 98, page 6/53).

Number of digital signal inputsas the sum of alarms, breaker and iso-lator positions, tap changer positions,binary coded meter values, etc, to beacquired, processed or monitored.Position monitoring requires doublesignal inputs while single inputs aresufficient for normal alarms.

Number of analog inputsdepends on the number of voltages,currents and other analog values(e.g. temperatures) to be monitored.Currents (rated 1 A or 5 A ) or voltages(normally rated 100 to 110 V) can bedirectly connected to the bay controlunits. No transducers are required.Numerical protection relays also acquireand process currents and voltages.

Fig. 116: Typical distribution-type substation

Local and Remote Control

Fig. 117: Typical I/O signal requirements for a trans-former bay

Control

Isolator HV sideCircuit breaker HV sideIsolator MV sideCircuit breaker MV sideTap changer, higher, lower

Data acqusition

1 x DSI1 x DSI1 x DSI1 x DSI8 x DSI

1 x SSI1 x SSI3 x V, 3 x J, 8 xϑ

Isolator HV sideCircuit breaker HV sideIsolator MV sideCircuit breaker MV sideTransformertap-changer positionsAlarm Buchholz 1Alarm Buchholz 2Measuring values

SSIDSIDCOSCO

Single signal inputDouble signal inputDouble commandSingle command

2 x DCO2 x DCO2 x DCO2 x DCO2 x SCO1 x SCO

M

I

V

50/51

87T

M

M

HV

RTD's

6MB5240-2 7SJ511 7UT512

To the centralcontrol unitOF

OFOF

M

MV

63

Incoming transformer bays

5 feeders

Typical distribution-type substation

115 kV

13.8 kV

115 kV

13.8 kV

5 feeders

They can also be used for load monitor-ing and indication (accuracy about 2% ofrated value). In this way, the number ofanalog inputs of the bay control unitscan be reduced. This is often practisedin distribution-type substations.

The device selection is discussed at thefollowing example.

Example:Substation control configuration

Fig. 116 shows the arrangement of atypical distribution-type substation withtwo incoming transformers, 10 outgoingfeeders and a bus tie.The required inputs and outputs at baylevel are listed in Fig. 117 for the incomingtransformer feeders and in Fig. 118 for theoutgoing line feeders, the bus tie and thev.t. bay.Each bay control unit is connected to thecentral control unit via fiber-optic cables(graded index fibers).The o/c relays 7SJ60, the mini-compactI/O units 6MB5250 and the measuringtransducers 7KG60 each have RS 485communication interfaces and are connect-ed to a bus of a twisted pair of wires.A converter RS485 to fiber-optic is there-fore additionally provided to adapt the seri-al wire link to the fiber-optic inputs of thecentral unit.Recommendations for the selection ofthe protection relays are given in the sec-tion System Protection (6/8 and followingpages).The selection of the combined control/pro-tection units 7SJ531 is recommendedwhen local control at bay level is to be pro-vided by the bay control unit. The low-costsolution 7SJ60 + 6MB5250 should beselected where switchgear integratedmechanical local control is acceptable.

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Local and Remote Control

Fig. 118: Typical I/O signal requirements for feeders of a distribution-type substation

51

M

51

M

51

M

51

M

51

To load dispatchcenter

Centralcontrolunit

To transformerfeeders

7KG60 6MB5250

7SJ60 6MB5250

6MB5250

7SJ60 7SJ531 7SJ531

6MB513

RS485/O F

RS485

1 x DSI

1 x DSI

1 x DSI

5 x SSI

Isolator

Grounding switch

Circuit breaker

5 alarms

Load currents are taken from the protection relays

Bus tie

1 x DSI

9 x SSI

Circuit breaker

9 alarms

Control

2 x DCO Circuit breaker

Per feeder

1 x DSI

1 x DSI

1 x DSI

5 x SSI

Isolator

Grounding switch

Circuit breaker

5 alarms

Measuring values(3 x V, 3 x I) from protection

2 x DCO Circuit breaker 2 x DCO Circuit breaker

OFOF

OF

Per feederVoltage tronsformer-bay

1 x 7KG60

GPS

VDU Printer(option)

Massstorage

7SJ60

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Enhanced remoteterminal units 6MB551

The 6MB55 telecontrol system is based onthe same hardware and software modulesas the 6MB51/52 substation control sys-tem. The functions of the inupt/output de-vices have been taken away from the baysand relocated to the central unit at stationcontrol level. The result is the 6MB551 en-hanced remote terminal unit (ERTU).Special plug-in modules for control andacquisition of process signals are usedinstead of the bay dedicated input/outputdevices: Digital input (32 DI) Analog input (32 AI grouped,

16 AI isolated) Command output (32 CO) and Command enablingThese modules communicate with thecentral 6MB modules in the same framevia the internal standard LSA bus. The buscan be extended to further frames by par-allel interfaces.The 6MB551 station control unit thereforehas the basic structure of a remote termi-nal unit but offers all the functions of the6MB51/52 substation control system suchas: Operating and monitoring from station

control level Serial connection of numerical protection

equipment Archiving of process results and events Implementation of automation tasks.

The following options are possible: Radio clock Serial interfaces to system control

centers (up to 3) with separate commu-nication protocols each, as applicable

Up to 64 serial fiber-optic interfaces todistributed bay control units

Expanded measured-value processing Logic and automatic programs Mass storage Up to 5 expansion framesConfiguration including signal I/O modulescan be parameterized as desired.Up to 121 signal I/O modules can be used(21 per frame minus one in the baseframefor each expansion frame, i.e. totally6 x 21 – 5 = 121).The 6MB551 station control unit cantherefore be expanded from having simpletelecontrol data processing functions toassuming the complex functionality of asubstation control system.

Local and Remote Control

The same applies to the process signalcapacity. In one unit, more than 4 000 datapoints can be addressed and, by means ofserial interfacing of subsystems, this figurecan be increased even further.The 6MB551 station control unit simplifiesthe incorporation of extensions to the sub-station by using the decentralized 6MB52*input/output devices for the additional sub-station bays.These distributed input/output devicescan then be connected via serial interfaceto the telecontrol equipment. Additionalparameterization takes care of their actualintegration in the operational hierarchy.The 6MB551 RTU system is also availableas standard cubicle version SINAUT LSACOMPACT 6MB5540. The modules andthe bus system have been kept, the rackdesign and the connection technology,however, have been cost-optimized (fixedrack only and plug connectors).This version is limited to a baseframeplus one extension frame with altogether33 I/O modules.

Fig. 120: 6MB551 enhanced remote terminal unit, in-stalled in an 8MC standard cubicle with baseframeand expansion frame

Fig. 119: Protection and substation control with the enhanced terminal unit 6MB551

Switchgear interlockbay unit 8TK1

Enhanced terminal unit 6MB551

Switchgear interlockmaster unit 8TK2

Station protection7SS5

… …

Input/output device6MB52*

Extension to substation

Stationcontrollevel

Serial interface

Station control center (option)Systemcontrol center

Central evaluationstation (PC)

Remote controlchannel

Radio time(option)

Telephone channel

1 n

Baycontrollevel

Protection relay7S/7U

Substation

Parallel interface

Marshalling rackTransducers andrelays interposing

(option) (option)

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MinicompactRTU*

Compact RTU

* Further 3 minicompact RTUs can be serially connected in cascadefor extension (maximum distance 100 m)With switching-current checkPotential free

6MB552-0A6MB552-0B6MB552-0C6MB552-0D

Type Serial portsto controlcentres

6MB5530-0A6MB5530-0B6MB5530-0C

Design Singlecommands

Alarminputs

Analoginputs

888

Remote ter-minal unit withcable shieldcommunication(RTC)

TelecontrolsystemSINAUT RTU

Serial portsto bay units

6MB5531-0A6MB5531-0C

6MD2010

88

331)/8331)/8331)/8

8

up to 2000 data points,

configurable

82432

832

7240

104136

–8–

––

32162)

––

1

1

1additionalgateway

2

7

2)

1)

Local and Remote Control

Remote terminal units (RTUs)

The following range of intelligent RTUs aredesigned for high-performance data acqui-sition, data processing and remote controlof substations. The compact versions6MB552/553 of SINAUT LSA are intendedto be used in smaller substations, whilethe version 6MD2010 of SINAUT RTU hasthe full functionality for control of largesubstations with up to 2000 data points.

Fig. 121: 6MB552 compact RTU for medium processsignal capacity

Fig. 122: 6MB5530-0 minicompact RTU for smallprocess signal capacity

Fig. 123: 6MB5530-1 remote terminal unit (RTC) withcable-shield communication

Fig. 124: 6MD2010 telecontrol system for largeprocess signal capacity

Fig. 125: Remote terminal units, process signal volumes

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Local and Remote Control

RTU-interfaces

The descripted RTUs are connectedto the switchgear via interposing relaysand measuring transducers (± 2.5 to± 20 mA DC) (Fig. 126). Serial connectionof numerical protection relays and controlI/O units is possible with the compact RTUtype 6MB552.The communication protocols for the serialconnection to system control centers canbe IEC standard 870-5-101 or the Siemensproprietary protocols 8FW.For the communication with protectionrelays, the IEC standard 870-5-103 is im-plemented.

Automation Functions

The SINAUT RTU telecontrol system isbased on SIMATIC S7-400, which providesnumerous communication options and auniversal automation system. Forthe user, it opens up the possibility to in-troduce project-specific functions for localautomation tasks. They can be configuredwith minimum engineering effort, com-bined with the features offered by theuser-programmable SIMATIC S7-400 auto-mation system.A typical task is the central monitoring orcontrol and automation of geographicallywidespread processes, such as networksfor electricity, gas, water, sewage, districtheating, oil, pollution control, traffic andindustry.

Fig. 126: RTU interfaces

Fig. 127: VF coupler with ferrite core 35 mm

Modem

Telecontrol channel

Modem

Interposing relays, transducers

Systemcontrolcenter

Substationlevel

Bay level

RTU

Existing switchgear

Marshalling rack

Extended switchgear

* * *

Optical fiber

Protectionrelays andI/O units

* Only for compact RTU 6MB552

Cable-shield communication

The minicompact RTU can be deliveredin a special version for communication viacable shield (Type 6MB5530-1).It does not need a separate signaling link.The coded voice frequency (9.4 and9.9 kHz) is coupled to the cable shield witha special ferrite core (35 mm window di-ameter) as shown in Fig. 127. The specialmodem for cable-shield communication isintegrated in the RTU.Fig. 128 shows as an example the struc-ture of a remote control network formonitoring and control of a local supplynetwork.

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Local and Remote Control

Fig. 128: Remote control network based on remote terminal units with cable-shield communication

Higher telecontrol level

Distribution station

ModemChannel 1 Channel 2

Mini RTU6MB5530-1 (RTC)

Substation

ModemChannel 1 Channel 2

Mini RTU6MB5530-1 (RTC)

Power cable (typically 5 km)

Signalloop

Signalloop

VF couplers VF couplers VF couplers

VF couplers VF couplersVF couplers

Power cable (typically 5 km)

Modem(optional)

Multiplexer(optional)Modem

Channel 1 Channel 2

Communicationcontrol unit

6MB5530-1 (CCU)

1st station of branch 8

1st station of branch 1

VF couplers

ModemChannel 1 Channel 2

Distribution station

Mini RTU6MB5530-1 (RTC)

16th station of branch 1

Substation

ModemChannel 1 Channel 2

Mini RTU6MB5530-1 (RTC)

16th station of branch 8

VF couplers

1 2 3 4 5 6 7 8

…… Branch 2

Branch 1

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Local and Remote Control

Fig. 130: Compact central control unit 6MB514

Fig. 129: Compact central control unit 6MB513

6MB5130

Side view Rear view Panel cutout

17229.5

266

37 39

277.5

244

2257.313.2 220 13.2

7.3

5.4

ø 6

ø 5 or M4

255.8

206.5

180

221

245

All dimensions in mm.

Panel cutoutand drilling dimensions

6MB5140

Side view Rear view Panel cutout

7.3

5.4

ø 6

ø 5

255.8

431.5405

446

245

13.2

266

17229.5 37 39

277.5

4507.313.2 445

All dimensions in mm.

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Local and Remote Control

Fig. 131: Compact input/output device 6MB522

Fig. 132: Compact input/output device 6MB523

Fig.133: Compact I/O unit with local (bay) control 6MB524-0, 1, 2

6MBB522 Side view Rear view Panel cutout

FSMA-optical-fiberconnector

7.3

5.4

ø 6

ø 5 or M4

255.8

180

245

206.5

221

220

225

244

30 29.5

231.5277

266

4

All dimensions in mm.

6MB524-0, 1, 2 Side view Rear view Panel cutout

255.8±0.3

Terminalblocks

7.35.4

ø 6

ø 5 or M4

206.5±0.3

180±0.5

221+2

245+1

13.2225220

F E CD B A

1234

5678

Optical-fibersocketsAll dimensions in mm.

3017229.5

266

9

244

Terminalblocks

6MB523 Front view Side view Panel cutout

244

231.5

30 29.5145

160

7.3

5.4

ø 6ø 5

255.8

105

245

131.5

146All dimensions in mm.

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6MB5240-3

17229.5

266

30 7.3

5.4

ø 6ø 5

Side view Rear view Panel cutout

431±0.3

405±0.5

446+2

244 245+1

13.2450

445

F E CD B A

1234

5678

255.8±0.3H GK JML

Optical-fiber socketsTerminalblock

All dimensions in mm.

9

Terminalblock

Local and Remote Control

Fig. 134: Compact I/O unit with local (bay) control, extended version 6MB5240-3

Fig. 135: Minicompact I/O device 6MB525

17229.5

266

37

244

Terminalblock

7570 7.3

ø 6

ø 5or

M4

71+2

56.5±0.3

245+1 255.8±0.3

6MB525

Side view Panel cutoutRear view

All dimensions in mm.

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Local and Remote Control

Fig. 137: Minicompact RTU 6MB5530

All dimensions in mm.

6MB5530-0 and -1

Front view Side view Rear view

300

22515

400

1.5

35

45

Cable bushing

200

20

20 18

20

20 10

25

A

A

8

8.2

Section A-A

Wall mount

Fig. 136: Compact RTU 6MB552 in 7XP20 housing

6MB552

17229.5

266

39

225

244

7.3

5.4

ø 6

ø 5 or M4

Side view Rear view Panel cutout

220

8

1) 2)

13.2206.5 ±0.3

180 ±0.5

255.8 ±0.3

221+2

245+1

Bus cover

BNC socket forantenna

Optical-fiber socketFSMA for connectionof bay units

All dimensions in mm.

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Introduction

Measurement and recording technologyfor electrical networks: a field with a longtradition at Siemens. More than 3,500Siemens systems, installed in 65 countriesaround the world, record, meter, conditionand transmit electrical signals – tasks theyperform with a proficiency that’s particular-ly effective when faults occur. Measure-ment and recording equipment for powersystems: a field where our innovation po-tential and know-how define the range ofproducts available on the market – fromanalog transducers (AFM) systems tointelligent recording systems such asthe OSCILLOSTORE® P351, productsequipped with analytical software basedon expert systems.

OSCILLOSTORE P:Systematic troubleshooting

The ability to minimize plant faults anddowntime while optimizing machine andresource utilization: that’s the secret ofsuccess of the OSCILLOSTORE P531.In production, faults which would normallylead to process errors and stoppages aredetected while still in their early stages.The P531 keeps self-extinguishing, tran-sient, semitransient and permanent faultsunder tight control in all major power sup-ply operations.The OSCILLOSTORE systems are alsowidely used in computer centers to moni-tor the quality of the power supply andrecord the history of faults.Clear fault detection, precise documenta-tion, reliable evaluation – all the hallmarksof the OSCILLOSTORE P system.

Also active in monitoring and analyzingthe quality of the mains supply

An optimum solution for every task:this is the founding principle on which theOSCILLOSTORE P product range wasbased. Another member of the family isthe QUALIMETRE®/OSCILLOSTORE P512,developed in cooperation with the EDF(Electricité de France), for recording thequality of mains supplies.And the OSCILLOSTORE P513, a portableunit with integrated analytical software,completes the lineup.

The real-time specialists:OSCILLOSTORE Esequence-of-events recorders

OSCILLOSTORE E systems are idealfor a wide range of tasks in the real-timeacquisition of digital signals. Siemensprovides both stand-alone equipmentand intelligent integrated solutions forthe SIMATIC range of programmablecontrollers.Customized applications in power plants,switchgear and industrial production pro-cesses are just some of the strengths ofOSCILLOSTORE E systems. And, with thetrend towards increased levels of automa-tion, real-time acquisition with a resolutionof 1 ms is a capability that makes thesesystems highly popular.

OSCOP:The trendsetter in application software

One thing is clear: the better the software,the more the user benefits. And this iswhere OSCOP stands out from the field.The OSCOP software is based on the MSWindows user interface, a fact that alreadyspeaks for itself. Remote calibration, datatransmission and PC-based evaluation havelong been standard concepts in power uti-lity recording technology. The OSCOP sys-tem software forms the actual core of therecording data networks and combinesautomatic operation with the high function-ality required by field specialists.

SIMEAS TThe modular transducer system:An ideal state-of-the-art solution

Digitization does not herald the demiseof analog transducing. Quite the opposite,in fact: power generation and distributioncontinues to rely on the ideally refinedmodular solution of the 7KG61 series.That shouldn’t come as a surprise consid-ering the wide range of user-friendly ana-log measurement transducers availabletoday.An increasingly significant role is, however,being played by the programmable numeri-cal transducers 7KG60. They allow meas-urement of all measurands with just oneinstrument. The advantages for users areclear: enhanced cost efficiency of stocks,simplified menu-guided PC operation anda reduction in the number of differentproduct types. The serial interface furtherallows the integration of 7KG60 transduc-ers directly into microprocessor-based con-trol and automation systems.

Measurement and Recording

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Fault recording

OSCILLOSTORE P531 and OSCOP P –The digital fault recorder with diagnosisand evaluation software

OSCILLOSTORE systems like the P531have been standing watch in renownedutility companies for years, looking out forself-rectifying, transient, semitransient,and permanent faults.In computer centers and in industrialplants, they monitor the quality of the pow-er supply and document the fault history.What is well recorded can be better evalu-ated – one of the more pleasing aspects ofaccurately recording electrical signals.Thanks to this source of information, onecan now optimize operating resources –and simultaneously minimize down-timeand avoid defects of equipment.The fault diagnosis in electrical power sup-ply is efficiently automated, thus facilitatingthe expert’s work.Fault recorders must be capable ofprocessing a wide variety of signals. TheOSCILLOSTORE P531 has the right solu-tion for this: Up to 31 data acquisition units (Fig. 141)

can be connected to the central unit –even when they are remotely installed atdistances up to two kilometers from theprocess

The modules are ideally equipped forsignal matching and digital preprocess-ing – even if the application requires a1 MWord of storage capacity

Still more important is that:The OSCILLOSTORE P531only records what you really need!Whoever needs to evaluate data, needsdata reduction (which the system memoryalso employs to reduce its load).

The OSCILLOSTORE P531embodies this principle:

It records only the anomalies, thanks tothe built-in start selectors! This includesthe fault history (the troublefree periodpreceding the fault), the fault itself, andthe fault’s sequel (the period after the faultoccurred). High-functionality start selectorsare available for each channel, and aresoftware-controlled.The system recognizes the fault character-istics itself, which means that the record-ing time is automatically adapted to eachrecording.

And what’s more: even prolonged distur-bances don‘t cause any problems. Therecording time is always adjusted to thesignal characteristics. Automatically, ofcourse. Channel-related inhibit functionseffective-ly prevent memory overflow, e.g. in caseof intermittent faults on one (or more)phase(s).Before the recorded data is stored in theacquisition module, the FDAU and PDAUmodules calculate any necessary quantities– for example, active power, reactive pow-er, and power factor. Because measurandtransducers are an integral part of themodules, external transdurcers are not re-quired. User-programmable gradient crite-ria allow to select the optimum momentfor recording – which again is a contribu-tion to data reduction.

Five data acquisition units capture andprocess all kind of measuring signals: ADAU (Analog Data Acquisition Unit)

– replaces the traditional fault recorderwith 4 channels for the real-time record-ing of currents and voltages, scanningrate 1 to 5 kHz adjustable per channel;storage capacity 50 to 250 sec.

BDAU (Binary Data Acquistion Unit)– replaces the sequence-of-eventsrecorderwith 32 channels for recording digitalstatus changes; scanning rate 1 kHz;storage capacity 900 status changes

DDAU (DC Data Acquisition Unit)– replaces the process recorderwith 4 channels for recording processvariables (e.g. 0 to 20 mA or 0 to10 Volt); scanning rate 0.2 Hz to 5 kHzadjustable; storage capacity 50 sec to14 days.

FDAU (Frequency Data Acquisition Unit)– replaces the frequency recorderwith 4 channels for recording the powersupply frequency; resolution 1 mHz;storage capacity 50 sec to 14 days.

PDAU (Power Data Acquisition Module)– replaces the power and frequencyrecorderwith one channel for recording the ac-tive power, reactive power, power factor,and optionally, the power supply fre-quency or rms voltage; storage capacity50 sec to 14 days.

Measurement and Recording

Fig. 140: Fault record

Fig. 138: OSCILLOSTORE sys-tems are used in power plants…

Fig. 139: … and to monitor transmission lines.

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Fig. 141: Distributed fault recording system

Fig. 142: OSCILLOSTORE P531, rear view Fig. 143: OSCILLOSTORE P531, front view

Data concentratorDAKONwith software forautomatic data collection,archiving and diagnosis

Control +communication unit

RS485-Bus

Central unitOSCILLOSTORE P531

1 2 3 30 31Analog or binary dataacquisition modules

Distributed fault recording system

Remote TransmissionTelephone network, X.25, ISDN; LAN; WAN

”Local Printer“

Evaluation station withsystem software OSCOP P

Further OSCILLOSTOREunits

Further OSCILLOSTOREunits

The DAU (Data Acquisition Units) allowsdecentralized as well as centralized intelli-gent data acquisition and processing. Therecorders can be linked to a central unitand can communicate with PC/AT compati-ble evaluation systems via modem – or viaa ”dedicated line“ if no modem is availa-ble. Depending on the application, front-end data concentrators with mass memory(DAKONs) can also be integrated usingstandard software. And the same standardsoftware allows a data network of faultrecorder systems to be set up.High-quality acquisition deserves high-quality evaluation. And that’s what onegets with the OSCOP P system program.This system is designed for all kinds ofperformance demands – thus tailored to fitwith any user requirements. It is availablein all major languages. And, of course, it issupported by an around-the-clock hotlineservice and our software maintenanceservice.In addition, the Siemens experts offer theircompetence for the analysis of the datarecorded and provide assistance in findingthe optimum solution based on the net-work topology.

Measurement and Recording

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OSCOP P is also open for other systems

In particular when monitoring the operatingresources, it is important that the informa-tion stored in these resources is also avail-able. Via an additional function of OSCOP Por directly on the DAKON, it is thus possi-ble to read the records and operating mes-sages of numerical protective relays.For data in the IEEE (Comtrade) standardformat, import and export functions areprovided.This functionality allows to compare the”subjective“ data of the operatingresource with the ”objective“ data of theOSCILLOSTORE P531.

Fig. 144: OSCOP P operating surface

Measurement and Recording

OSCOP PThe user software withautomatic diagnosis

There are no communication problems be-tween OSCOP P and the OSCILLOSTOREP531 central units. Up to 100 of them(each with up to 31 acquisition modules)can communicate with the software viathe public telephone network. All parame-ters can be set up remotely.OSCOP P has a built-in database whichreceives the measured values and theirrelated parameters. It can be used as acentral archive. The filter functions alloweasy retrieval of the archived data evenafter years.The MS Windows operating system is par-ticularly suited because of its ease-of-useand the efficient time-sharing characteris-tics (that means, the recorded data can beevaluated in foreground, while the data isbeing transferred and an automatic diagno-sis performed in the background).We make the plant management’s lifeeasier with time-controlled automaticoperation and automatic screen display.This includes the option of a fault printoutwith analysis so that one can store andanalyze results without pressing a button.And the diagnostic system provides forperfect automatic analysis.If the OSCILLOSTORE P531 is used tomonitor high-voltage supplies and cables.The diagnostic system is a powerful ”faultlocator“. No longer will line and cablefaults go undiscovered, they are pinpointedwith a high degree of accuracy.

DAKON with OSCOP P for decentralizedautomatic diagnosis

All these automatic functions (diagnosis,r.m.s. values, fault locator ...) can also beperformed on the local DAKON, e.g. in theswitchyard. This solution allows you to stillreduce data for the remote transfer sothat only the relevant information and, ifrequired, the “r.m.s. values window“ aretransferred. Data archiving in the DAKONdatabase can efficiently relieve the centralevaluation station.

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Power quality assessment

QUALIMETRE*/OSCILLOSTORE P512

All functions of a completeequipment family in one unit

Previously a multitude of instruments wasrequired for recording variables – nowQUALIMETRE does it all alone. It replacesvoltmeters and ammeters, active- and re-active-power recorders, harmonics analyz-ers, RMS value recorders and much more.Of particular advantage for the user is theparallel recording of all significant networkdata. QUALIMETRE monitors all the elec-trical characteristics of a network. This isa real benefit, because faults of a widelydiffering nature may occur: Voltage variations

– Changes in amplitude (differencebetween maximum and minimumvoltage)

– Surge voltage (sudden amplitudechange)

– Voltage fluctuation (number of chang-es in amplitude within a specific time)

Long-time interruptions (such as com-plete power failure for more than 1 min)

Short-time interruptions (such as com-plete power failure between 10 ms and1 s or 1 s and 1 min)

Voltage drop(changes in amplitude over a longperiod)

Asymmetry (differing voltage amplitudesand/or phase angles)

Harmonic components of the fundamen-tal wave

QUALIMETRE can be used both for exam-ining and monitoring supply networks.

Immune to transient overvoltages

QUALIMETRE can be easily installed nearswitchgear and industrial supply circuits.To cope with this environment, measuringinstruments must have special propertiesin oder to operate reliably despite transientovervoltages. QUALIMETRE has thereforebeen designed in accordance with IEC 255protection standards with interference im-munity in mind.Spurious peaks of 2.5 kV, 1 MHz do notimpair the measurement result – an insula-tion voltage of 2 kV is included, naturally.

Measurement and Recording

Fig. 145: QUALIMETRE*/OSCILLOSTORE P512

* QUALIMETRE is a joint development of Siemens andEDF (Electricité de France). EDF, a world leader in qual-ity assurance of supply networks, was responsible forthe functionality of QUALIMETRE, and Siemens pro-vided the know-how for OSCILLOSTORE, the provenfault monitor.

Designed for installation

QUALIMETRE includes the necessary sig-nal conditioner for current and voltage andis therefore particularly suitable for perma-nent installation.For stationary operation a 19" rack-mount-ed model of compact design is offered.

QUALIMETRE saves paper

It is fairly obvious that large amounts ofdata come up in continuous network re-cording. In conventional instruments thisquickly leads to a flood of paper.Not so with QUALIMETRE: The datameasured is stored electronically. Remoteparameter input, data transmission andevaluation are thus also possible – theproven OSCOP evaluation programs takecare of this. Transmission of data via thepublic telephone network is also optimizedthanks to an integrated modem.The modern design concept permits easyexpansion with portable data carriers andtransient detection and flicker meter func-tions.All in all, there are many advantages withQUALIMETRE, making it the ideal solutionfor monitoring and analysis in electricalsupply networks.

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OSCILLOSTORE P513For measurement, recording,and evaluation:

OSCILLOSTORE P513 is a new portableinstrument for continuous analysis anddocumentation of the quality of powersystems at any location.

Ideal for power companycustomer service technicians

The generation and distribution of electricalpower in the desired quality and quantityare taken for granted today.Nevertheless, customers sometimes re-port that their supply is not as it should be,and disturbances fed back into the systemcan lead to a loss of quality in the utility’sproduct-electrical energy.In such cases, the customer service tech-nician is called upon to measure and ana-lyze the quality of the electrical powerdelivered to the customer – whether theproblem appears at a privat residence, asmall business, a medium-sized operation,or a large corporation.The OSCILLOSTORE P513 is just the in-strument you need to obtain fast, accurate,reliable and meaningful information on thespot.That means one can analyze and recordmeasurement data in the field applyingconsistent evaluation criteria to data ob-tained simultaneously, without having toconnect several different instruments.Additionally, results can be read out on thespot, making it even easier to get systemproblems under control.It is further possible to check the perform-ance of uninterruptable power supplies,and also to record the signal shape at con-verters and inverters.The OSCILLOSTORE P513 determinesall relevant system parameters: voltage,current, frequency, and harmonic contents,as well as active and reactive power.Even on the low voltage level, the OSCIL-LOSTORE P513 ensures high-precisionmeasurements, so that it can even beused at the ”wall socket“ level.Of course, all of the P513’s functions, in-cluding the 12 measurement functions,are housed in a single unit, which even in-cludes a built-in floppy drive and printerand, as a special feature, an integratedevaluation program.

The P513 is an intelligent, portable measur-ing instrument that monitors all of the char-acteristic electrical parameters on a powersystem: 8 measurement channels for continuous

recording of:– Voltage– Current (both with r.m.s. value calcu-

lation over one period)– Transient voltages with 2.6 kV peaks

at a 2 MHz sampling rate Continuous calculation of:

– Frequency– Phase angle in tan phi/cos phi– 1- to 3-phase active and reactive

power (all connection types possible)– Harmonics up to the 50th order.

Averaging times and recording times in therange from one period to 9999 hours canbe selected for all measurement types

See what’s going on right now –without losing the big picture

All measurement results can be displayeddirectly on the built-in screen, either nu-merically or graphically as an XT diagramor a bar graph.Vertical and horizontal zoom functions areprovided so that one can examine relevantsignal patterns in detail using the cursor.When one selects the histogram display,one can see at a glance the complete re-cord of voltage and current levels and theirstatistical distribution during the monitoringperiod.

FIg. 146: OSCILLOSTORE P5 13

Measurement and Recording

A backlit LCD display is also provided tomake it easy to read all the information onthe screen clearly – without depending onthe local lighting conditions.The information can be printed out on anyscreen as a hard copy at any time.

Transient voltage measurement section

One of the many features of the OSCIL-LOSTORE P513 is the separate measure-ment section with integrated transient volt-age recording unit. It is isolated from therest of the electronics using fiber optics.Thus, a complete electrical isolation is ob-tained. It means that one can measuremore confidently than ever before, withoutworrying about feedback. Complementingthis design is the P513’s ability to recordtransient peaks up to 2.6 kV at a scanningrate of 2 MHz.

Memory for morethan half a million readings

The built-in memory of 1.4 Mbyte makesit possible to store up to 500,000 readings.And the OSCILLOSTORE P513 is just asimpressive when it comes to convenience: Because of the P513’s large memory

capacity, it is ideally suited to long-termmonitoring. Depending on the parametersettings used, up to over 1 year of datacan be recorded!

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Measurement and Recording

Fig. 147: Measuring transducer 7KG60, block diagram

Fig. 148: Measuring transducer 7KG60

Fig. 149: Measuring transducer 7KG60, dimensions

Digital output

Analog output 1

Analog output 2

Analog output 3

Serial interface

UH

IL1

IL2

IL3

UL2

UL3

UL1

N

Block diagram

RS 232RS 485

AC

75

90

Front view

Side view

Connection terminals

All dimensions in mm

90105

SIMEAS T –Universal transducers for electricalquantities in power systems

Areas of application

With the SIMEAS T universal transducer(Order designation 7KG60) all measurandsin any desired power grid can be measuredwith just one instrument.The instrument is equipped with 3 electri-cally isolated analog outputs, a digital out-put, and a serial interface.Each analog output can be assigned an in-dividual measurand (current, voltage, activepower, reactive power, etc.) and any de-sired measurement range.The measurement is a real/r.m.s. measure-ment, which can also measure distoredwaveforms and waveforms with a largeharmonic content.The output signals (e.g. 0 to 10 mA, 4 to20 mA, 0 to 10 V, etc.) can also be user-programmed for each output.The digital output can be used as a triggeroutput for recording the results, or as alimit signal.Any desired input current or input voltageup to maximum of 10 A or 600 V, can beconnected at frequencies between 45 and65 Hz (16 2/3 Hz). Depending on the mea-surement task, the unused input terminalsremain free.The transducer can be ordered either pre-configured in accordance with plaintextspecifications, or programmable with thecapability for a custom setup.Setup data and a specific connection dia-gram are delivered with factory set instru-ments. Programmable instruments canprint out this data as required.A PC connecting cable and a disk contain-ing Windows software, with which onecan easily set up the transducer oneself,can be ordered optionally.During operation you can reprogram thetransducer, or display the measured valueson-line on a graphics instrument (containedin the software), either on a PC or on-siteusing a laptop.The instrument requires an auxiliary powersupply. Variants are supplied for the AC/DCranges from 24 to 60 V, and from 100 to230 V.Inputs, outputs, and the auxiliary powersupply are electrically isolated from oneanother.

Serial interfaces

The RS232/RS405 interface of the 7KG60can be used to communicate with a PC forsetting and readout of data or to integratethe transducers as measuring-data acquisi-tion units into substation control systems.In the latter case, an IEC 870-5-103-com-patible protocol is used.

Design

The housed version of the transducer is ahardwired, certified functional unit. It hassnaptype catches for attachment to 35 mmtop hat rails (DIN EN 50022). Terminalscrews allow inputs and outputs to besecurely connected.The measurands and ranges of measure-ment can be configured as desired.

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Measurement and Recording

Fig. 150: Window for configuration of the output values Fig. 151: Calibration

Fig. 152: Display of 3 selected measurement values and measuring ranges

SIMEAS PAR

The software SIMEAS PAR consists of thethree following subprograms: 1. Configuration 2. Calibration 3. Data ExportSIMEAS PAR was designed for theMS DOS platform of common PCs or lap-tops. The program is operated via thegraphical user interface MS WINDOWSV3.1 by mouse and keyboard. Communica-tion with the transducer occurs via thestandard serial interface of a PC or laptopand an optional connection cable.

Description

1. Configuration (Fig. 150)

The “Configuration“ function allows set-ting of the variables, measuring ranges,output signals, etc. for the transducer. Itprovides the user with straightforward set-ting of the parameters in just a few steps.

Entering the data in the respective win-dows is simple and clear.This procedure is supported by additionaldialog guidance.If required, the following data can be print-ed on the local PC printer: Parameters entered The connection diagram of the specific

measuring task A self-adhesive configuration label with

the settings of the transducer

2. Calibration (Fig. 151)

Since the transducer does not include anypotentiometers or other hardware settingfacilities. Balancing the transducer is madevia the software with the ”Calibration“function.Generally, the transducers are deliveredwith factory-made calibration and setting.Recalibration is necessary only after repairwork or for rebalancing.The screens and graphical characteristiccurves of the ”Calibration“ subprogram arealso easy to operate.

A description of the test configuration andinstructions on the program operation areprovided by the help system.

3. Data Export (Fig. 152)

With graphics instruments, up to 9 mea-suring signals can be displayed on-line ona PC or laptop screen in analog and digitalform.For better resolution, the user can selectthe number of measuring instruments onthe screen and assign measuring signalsand ranges to the displays.The assignment does not depend on theanalog outputs of the device.If required, the measuring data can bestored or read to the local PC printer.

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Measurement and Recording

Hints for application

Fault recording

The OSCILLOSTORE P531 is used in allkinds of power systems to record fault his-tories for fast and precise fault analysis.It also supplements the fault recording ofnumerical relays with the following extend-ed recording capabilities: Independent recording of events with

high sampling rate (up to 5 kHz) andlong recording times (up to 14 days).

Integrated start selectors for recordingof frequency excursions and powerswings.

The recording channels are normallychosen as follows: Per busbar section:

4 analog values (4 x V) Per EHV bay:

8 analog values (4 x V, 4 x I)and 16 binary signals

Per HV bay:4 analog values (4 x I)and 16 binary signals

The following derivated values are addition-ally calculated and recorded: Frequency at busbar sections Optionally active, reactive power and

frequency at infeeds.

Power system quality

The QUALIMETRE/OSCILLOSTORE P512is normally installed at infeeds.It is general practice to record 8 channels:4 x V, 4 x I.

Measuring transducers

SIMEAS transducers are normally installedat busbars for voltage and frequencymeasurement, or at infeeds and feeders,where required, for the measurement ofactive/reactive power and cos phi.They can be connected to the low-voltagenetwork directly or to the secondary wind-ing of v.t.s and c.t.s. Standard rated inputvalues are for example 110/ 3 V and 1 or5 A.

The transducer outputs can either beanalog, for example, 4 to 20 mA (7KG61analog series) or serial at a RS485 port(7KG60 digital series). The transducers arein general used with devices that cannotbe directly connected to the LV networkor c.t.s and v.t.s. This range of devicesinclude meters, indicators, recorders andremote terminal units.The digital SIMEAStransducers (7KG60) series are intelligentelectronic devices (IEDs) that can be usedfor data acquisition and preprocessingof data. They can be directly connectedto control and automation systems throughtheir RS485 interface. Standard protocolIEC 870-5-103 is used for communication.

For further information please contact:

Fax: ++ 49-911-433-8589

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Power Systems Control

Contents Page

SCADA, EMS, DMS 7/2–7/5

Control Room Technology 7/6–7/10

Power NetworkTelecommunication 7/11–7/24

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SCADA/EMS/DMS

Introduction

The requirements on network control sys-tems are growing as secure and economicenergy management is becoming evermore important. Planning and implementa-tion of SCADA systems (Supervisory Con-trol and Data Acquisition), Energy Manage-ment Systems (EMS) as well as Distribu-tion Management Systems (DMS) involvecoordinating a wide range of engineeringtasks. Siemens is in a position to deliveroptimum, state-of-the-art solutions in closecooperation with the customers.SINAUT (Siemens Network Automation)is Siemens’ modern product family forPower Systems Control. It reflects the ex-perience of more than 540 electricity gridcontrol systems installed worldwide sincethe early sixties.As technological pacemaker Siemens in-vests considerable funds annually in thefurther development of the SINAUT prod-uct family. Planned for the long term, thisuser-oriented product line has release com-patibility to guarantee that the benefits oftomorrow’s R&D investments can still beadopted by systems delivered today.

Municipal utilities and Large industries with own networks Regional distribution utilities National and regional generation and

transmission utilities

Modular and distributed architecture

Each SINAUT Spectrum system consistsof individual functional subsystems whichare distributed among an optimum numberof workstations and servers. Shortest reac-tion times are achieved by assigning time-critical applications and applications requir-ing a lot of computation power to dedicatedservers (Fig. 1). The database is distributedamong the workstations and servers forfast and independent data access with lowLAN-loading.The modules of the network control sys-tem SINAUT Spectrum are shown inFig. 3 on page 7/4 and 7/5.Due to its modular and distributed systemarchitecture SINAUT Spectrum offersunlimited horizontal and vertical growthopportunities, e.g. from a small entry-levelSCADA system up to a large EMS or com-bined SCADA/EMS/DMS.

Siemens furthers this strategy by participat-ing in a variety of IEEE, IEC, EPRI, CIGREand CIRED committees and by enlistingsupport from active user groups.The quality management certified byDQS according ISO 9001 ensures qualityproducts and a smooth and reliable projectimplementation within contractual sched-ule and budget.Siemens Power Systems Control has alarge support staff of dedicated expertswith power industry experience.With its broad range of products Siemensis able to supply the control systems, allnecessary components (communicationequipment, control room equipment, un-interruptible power systems, etc.) fromone supplier on a turnkey basis.

SINAUT Spectrum

General

SINAUT Spectrum is the open, modularand distributed control system for electricalnetworks as well as for gas, water andremote heating networks.Its extensive and modular functionalityprovides scalable solutions tailored to theneeds and budgets of:

Basic componentsHot standby

Dataacqusition

Mimicdiagraminterface

Mimic diagram

SCADA

Administrator,archives,schedules

Networkanalysis

Operatorconsole

Power andschedulingapplications

Operatorconsole

Spare

Trainingsimulator

Expertsystem

Distributionmanagementfunctions

Bridge

Gateway

GIS PC

Communicationwith other controlcenters, e.g.ICCP or ELCOM-90

to/from RTUs

Data-base

Office LAN

LAN

Fig. 1: SINAUT Spectrum – system architecture of a large SCADA/EMS/DMS

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SCADA/EMS/DMS

SINAUT Data Gateway

SINAUT Data Gateway exactly meets therequirements of an integration tool neededfor data maintenance. With SINAUT DataGateway control center data can be main-tained with one database instead of main-taining modeling information in severaldifferent formats for each application. Forthe update of an existing control centersystem, the necessary data can simply beexported in a format recognized by thenew control center system.

Available services

Siemens offers services for all importantareas: Studies, planning, engineering Project implementation Installation, supervision of installation Commissioning Training Hardware/software maintenance System upgrading System migration

Siemens Power Systems Control– a key to success

Network Control Centers have to operateeconomically and efficiently over long peri-ods. Therefore Siemens is committed to: Designing systems that can incorporate

new standards and technologies overtime to keep the system current

Avoiding dependence on proprietarytools and methods

Using accepted and de facto standards Meeting the growing need for informa-

tion management throughout a publicutility company

The long-term commitments also include: A full product spectrum Complete turnkey projects Complete spectrum of services An active user group Strong R&D

For further information please contact:

Fax: ++49-911-4 33 -8122

Further SINAUT products

SINAUT ACESAccounting, Contracts andEnergy Scheduling

The volume of wholesale transactions willincrease dramatically due to regulatoryand economic pressures. SINAUT ACESprovides sophisticated software that canmanage commodity trading, accounting,billing, monitoring, and contract compli-ance. SINAUT ACES allows to take fulladvantage of the growing complexity ofcontract provisions. SINAUT ACES oper-ates within an open-systems environmentthat can be fully integrated with SCADA/EMS/DMS and corporate informationsystems.

SINAUT ICCPNET, SINAUT ICCPNTCommunications Products

Siemens offers a full range of communi-cation products which support ICCP.The field-proven SINAUT ICCPNET whichexecutes under UNIX, offers a commercialrelational database manager to handle con-figuration and object-set definition with anOSF/Motif operator interface.SINAUT ICCPNT executes on a PC plat-form and combines a low-cost solution andUCA (Utility Communications Architecture)open-systems technology in order to inter-connect utilities.

Open architecture

SINAUT Spectrum is solidly based onindustry standards. Therefore the systemcan be upgraded to take advantage of therapidly moving technology in the worksta-tion and server market, without losing anyof the software investment built up overthe years.SINAUT Spectrum runs under a UNIXoperating system, strictly adhering tothe IEEE POSIX standards, thus providinghardware platform independence.SINAUT Spectrum may be delivered eitheron SUN or on IBM workstations.The user interface employs a graphicalenvironment that the operator can tailor tohis specific tasks and preferences. Basedon the X-Window System and OSF/Motif,this user interface provides multiple-win-dow displays, full pan and zoom capabili-ties and excellent display call-up times.Other standards used inSINAUT Spectrum: Structured Query Language (SQL)

for relational database access TCP/IP for LAN/WAN communication IEC 870-5 as well as many other

protocols for RTU communication IEC 870-6 TASE 2 (ICCP), WSCC and

ELCOM 90 for communication withother control centers.

Fig. 2: Control room of Northern States Power Company, Minneapolis, MN

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SCADA/EMS/DMS

Network Control System

UNIX server Database

UNIXworkstation

Informationmanagementsystem

Dataacquisitionsubsystem

Userinterface

Gateway Computernetworkmanagement

Ethernet-LAN Tools fortest anddiagnostics

Communi-cation system

Softbus

RTU UNIXoperatingsystem

High-levellanguagecompiler

Archives andschedules

Dataacquisitionandprocessing

Supervisorycontrol,control jobs,manual update

Reportgenerationsystem

Dynamicnetworkcolouring

Operationoptimization forgas and waternetworks

Energydemandcontrol

Loadmanagement

Energyaccounting

Data importfrom a GIS

Tracing

Switchingproceduremanagement

Outagemanagementsystem

Loadmodeling

Onlineshort-circuitcalculation

V/Varcontrol

Spatialcontrol andqueries

Jumpers,cuts, grounds

Fault locationand isolation;servicerestoration

Feederestimation

Onlineload flowcalculation

Transformerloadmanagement

Cold loadpickup

Distributionmanagementfunctions

SCADAfunctions

Basicsystem

Hardware

Fig. 3: Modules of the network control system SINAUT Spectrum

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SCADA/EMS/DMS

Communication

Modelupdate

SINAUT Spectrum

Networkreduction

Stateestimator

Networkparameteradaption

Dispatcherpower flow

Faultcalculations

Securityanalysis

Networksensitivity

Optimalpower flow

Securitycheckedswitching

Voltagescheduler

Study casemanagement

Securitydispatch

Outagescheduler

Automaticgenerationcontrol

Interchangescheduling

Economicdispatch

Reservemonitoring

Interchangetransactionevaluation(A+B)

Loadforecast

Unitcommitment

Hydroscheduling

Hydrothermalcoordination

Productioncosting

Wheeling losscalculation

Waterworth valuecalculation

Instructorfunctions

Completefunctionalityof thecontrol system

User interfaceof thecontrol system

Processsimulation

Networkmodel

Generationmodel

Intelligentalarmprocessing

Disturbanceanalysis

Networkrestoration/load transfer

To othercontrol centers(ICCP)

Geographicalinformationsystem (GIS)

Multisitecontrol centeroperation

Other utilityIT systems

Planning

Maintenance

Protectionmodel

Billing

Expertsystem

Trainingsimulator

Power andschedulingapplications

Networkanalysis

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Control Room Technology

SINAUT Visualization

Introduction

With its SINAUT Visualization large-screenrear projection system, the Siemens AGoffers the solution for the large-screendisplay of text or graphics. Thanks to themodular design of SINAUT Visualizationwith projection modules which can stackedhorizontally and vertically without paths,screens of practically any size can be built.The SINAUT Visualization large-screen rearprojection system can be used whereevera large-area presentation of computer datais required. For example, in power distri-bution.SINAUT Visualization can be used in an en-ergy management system as a substitutefor or adddition to conventional mosaicpanels. All dynamic data, from an overviewof topological information about the areasupplied to detailed information and spe-cial messages for the operators in case offault, can be visualized so that all operatorscan read it (Fig. 4).

Description

Design of SINAUT Visualization-mX

The LCD projection technology used inSINAUT Visualization-mX is based on theTFT LCD (thin-film transistor liquid crystaldisplay) light-valve technology. This so-called active matrix LCD has a better con-trast and display switching rate than thelower-cost passive LCDs. Each individualred, green and blue color pixel of the LCDis controlled by a transistor that is, in turn,directly linked to the computer electronicsof the integrated mX-Terminal*.This eliminates color shift and drift effectsbecause no analog technology is used(Fig. 5).

Modularity

SINAUT Visualization-mX is a modularsystem in order to cover different require-ments for projection area, resolution andsize.Each projection module is an individual rearprojection system with a 50"-inch screenand a resolution of 640 x 480 or 1024 x768 pixels. It has no seam and the edgesof the module correspond with the pictureborders (Fig. 6).

* mX-Terminal designates the multiscreen-cablex-Terminal from Siemens AG

VGA, Video, X.11controller

Mirror, lamp

LCDlightvalve

Projection lens Screen Observer

Fig. 5: Principle of rear projection using an LCD

Fig. 6: Projection module with dimensions in mm

Illumina-tion unit

Darkbox

Screen module

340

1213

1000

750Screen

Fig. 4: Control room of Victorian Power Exchange, Australia

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Control Room Technology

Therefore seamless pictures of any sizecan be built by horizontal and verticalstacking of several modules.Fig. 7 shows an example of a 3 x 2 config-uration of modules, offering a resolution ofeither 1920 x 960 or 3072 x 1536 pixels.The more modules are configured horizon-tally or vertically, the higher is the resultingresolution. The projection modules can beset up in horizontal direction linear as wellas polygonal with an angle of 8 degrees toeach other in order to obtain a slightlycurved display wall. Other angles are pos-sible on request (Fig. 8).

Connectivity as mX-Terminal

The mX-Terminal integrated in OVERVIEW-mX and the X-server installed on it con-form 100% to the internationally standard-ized protocol definition X window system(X-Windows, X.11.). Up to 4 projectionmodules can be connected to one mX-Ter-minal. If they are arranged in a 2 x 2 de-signs, they provide a resolution of 1280 x960 or 2048 x 1536 pixels. The systemoperates like an X-Terminal with all X.11tool kits such as OSF/Motif and the X-appli-cations based on them. All X-clients canmake unrestricted use of the entire projec-tion area of 2 m x 1.5 m (Fig. 9).

Screen 0

Illumina-tion unit

Darkbox

Screen module

Screen 1 Screen 2

Screen 3 Screen 4 Screen 5

1213

3000

1500

Fig. 7: 3 x 2 horizontal and vertical stacking of projection modules

Operator Operator

SINAUTVisualization-mXprojection modules

mX-Terminal

Ethernet,TCP/IP X-Windows

Fig. 8: Linear or polygonal setup of several SINAUT Visualization-mX projection modules (top view)

Fig. 9: Integration of SINAUT Visualization-mX into a computer network based on Ethernet, TCP/IPand X-Windows

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Control Room Technology

Mosaic-tile systems

Introduction

Visualization of the electric systems to becontrolled and optimization of the workingenvironment are of utmost importance forthe control room operators’ ability to con-centrate.By combining the latest ergonomic find-ings with an appropriate design Siemensprovides an environment that allows theoperators to work well, even in criticalsituations.Control boards and mimic displays ofmosaic tile design must have a straight-forward layout. They must also be cost-effective and capable of being shaped tosuit customer requirements. It must bepossible to modify or extend them quickly,simply and at minimum cost.The ergonomics and design of Siemenscontrol rooms exceed the scope of all DINand international standards.A broad selection of standard modulesand components form the basis of our con-trol rooms. They range from mosaic tilesystems and control desks to large-screenrear projection systems, and from opti-mized mapboards to ergonomically perfectoperator workstations.Siemens manufacture of control roomtechnology is certified to ISO 9001.

Controlling of the mimic board

Control room technology by Siemenshas been developed generally over the lastfew years.Controlling of the mimic board is no longerdone by a costly 1:1 wiring system but viaan Ethernet bus (SINEC H1) tothe PLC (Programmable Logic Controller)system and an internal mimic board bus(SINEC L2).This new idea – Mimic Board Controlling(MBA-L2) – has been successfully realizedin several projects (Fig. 12).

LAN-controlled mimic board

The mimic board consists of the followingelements: PLC Power supply including fuses Bus terminal Main module for the control of

32 twincolored LEDs Extension module for the control of

32 twincolored LEDs Low consumption diodes Protocol as per DIN 19245

If more than 4 projection modules arerequired, there is the possibility to havenearly any number of modules as onelarge display. With the distributed X-Server(1 central device mX-Terminal with key-board and mouse and several renderingmachines) it is possible to control nearlyany number of modules as one singledisplay.

This means that both the user and theapplication software “see” one single dis-play. Installation, operation and service donot differ from that of a standard X-Termi-nal (Fig. 10).

6 mX-Terminals asrendering machines

mX-Terminalas central device

Ethernet TCP/IP,X-Windows

24 modules with3480 x 1920 pixels

DistributedX-Server

Workstations/Windows NT-PCs

Fig. 10: SINAUT Visualization-mX as 6 x 4 setup

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SINEC H1/Ethernet

PLC

1 SINEC L2 32

1

32

1

8

RS 4851 16

1 2 3 4

LED 32Mainmodule

LED 32Mainmodule

Displaysubmodule

1234 MW

Analogoutputsub-module

1 Power supply module

2 CPU module

3 CP to SINEC H1

4 CP to mimic boardIan SINEC L2

Control Room Technology

Online testParametrizingCommissioning

Mimic board

SINEC L2

SINEC 1/Ethernet

PLC

SINAUTspectrum

Description

The PLC from theS5 automation system consists of:

Power supply module Central processing unit (CPU) Communication processor module

to a host processor Communication processor module

(CP 5430) to internal LAN connectionof the mimic board

Eventual memory extensions in caseof bigger systems

The use and the selection of the differenttypes of S5 PLCs depend on the require-ments of the controlled LEDs and on theparameters which are to be transmittedfrom the host processor to the PLC.The communication processor to a hostprocessor is determined by the structureof the protocol and the physical interface(e.g. SINEC H1, L1, L2 and so on).

Fig. 11: Control room of Schluchseewerke AG, Germany

Fig. 12: Mimic board wiring with MBA-L2

The bus terminal

The bus terminal is designed to connectto the internal LAN one main module and16 extension modules. In addition to theLAN connections, the following are con-nected to the bus terminal: power supply,shielding for the cables between bus ter-minals and modules, and digital input forsynchronization of blinking.

The bus system, protocol structure

The LAN controlling the main module isan RS 485 interface. The protocol is ac-cording to DIN 19245 (profibus). This LANis supplied by a communication processorCP 5430 which supports the protocolDIN 19245 by hardware implementation.

Fig. 13: Hardware structure of MBA-L2

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Control Room Technology

Main module

The main module is connected by a16-pole cable including power supply,LAN connection and synchronizing input.Each main module is a slave partner onthe SINEC L2 LAN and is able to control upto 32 twincolored LEDs. The intensity ofthe LEDs can be controlled via messagesfrom the PLC. Thus the brightness of theindicator lights can be adapted to the lightconditions in the control room.The LEDs can be operated in steady-statemode (on/off) or in flashing mode with afrequency of 0.5 to 8 Hz in 5 steps.A red LED on the module’s rear side indi-cates following errors: LED failure Number and color (monocolored,

twincolored) of LEDs to be used donot match with the number of plug-inLEDs

Failure or error of RAM, EPROM,E2PROM

A green LED indicates healthy operation.Errors can be read out and failures canbe exactly located. LED failures can belocated as well. Thus detection and re-placement of defective LEDs are not time-consuming.A defective LED can also be found bya ”lamp test“ message (operation of allLEDs).Each main module can be used to controlup to 16 extension modules. Each exten-sion module will be addressed directlyover Profibus by a subaddress.

Extension module

The extension module can control up to32 twincolored LEDs. As described above,the extension module is addressed by amain module. Each extension module iscyclicly updated by the main module. Thismessage can be interrupted by messagesof higher priority. These are: Synchronous blinking Lamp testAll further functions of the extensionmodule are the same as described abovefor the main module.

8RT8RU8RS

SINEC H1-Bus

User software

CPU

Process anddistribution ofLED data

Standard interface

Data areas forLED information

Data preparation

SINEC L2-Bus

Fig. 14: Software structure of Mimic Board Controlling(MBA-L2)

Fig. 15: 8RU-8RS-8RT mosaic tile systems

Parameteriziation software

The menu-driven software allows design-ing of main and extension modules locallyat the module or on line during operation.

Features of MBA-L2

Automatic background LED test,faulty LED can be detected at any time

All errors can be located and transmittedto host computer system

Steady-state mode, on/off Flushing mode, 0.5 up to 8 1/s in

5 steps Smooth brightness control No need for marshalling racks or distri-

bution units Reduced number

of cable connections to and inside themimic board

Simple erection on site, no wiring Easy extension and modification

because of using plug-in technology

Mechanical Design

The 8RU-8RS-8RT mosaic tile systems areof self-supporting and self-locking design.The tiles are in fact designed to supportone another and thus give the finishedcontrol board or mimic display a strongstructure. No metal supporting grid or anyother extra parts are needed for mountingthe individual tiles.All the systems can be modified or ex-tended quite simply. Once the board hasbeen erected, mosaic tiles can simply beexchanged or added.The 8RU-8RS-8RT mosaic tile systemshave been tested to DIN 40046 seismicrequirements and are thus fully able towithstand heavy mechanical loads.

For further information please contact:

Fax: ++49- 911-4 33 -81 83

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AKEPLCCCCVTSWT F6FWTESBHicomSWT 2 DMUXLFHO.F.

Coupling unitPower line carrier communicationCoupling capacitorCapacitive voltage transformerTeleprotection signaling system for analog transmission linksTelecontrol – and data transmission systemPower line carrier systemISDN telephone systemTeleprotection signaling system for digital transmission linksMultiplex systemFiber optic transmission systemOptical fiber cable

AKE

Distance protection

50 ... 2400 Bd

64 kbit/s

Hicom

Line trap

CC or CVT

SWT F6

FWT

ESB

SWT D

LFH

MUX

Dig. currentcomparison anddistance protection

Data50 Bd ... n x 64 kbit/s

Speech

up to 500 km

O.F.

PLC

Fig. 16: General overview

Power Network Telecommunication

Introduction

Safe, reliable and economical energysupply is also a matter of fast, efficientand reliable transmission of informationand data.International operation, automation andcomputer-controlled optimization of net-work operations, as well as changing com-munications requirements and the rapidchange in technology have considerablyincreased the demands placed on systemsand components of communications net-works.The same careful planning and organizingof communications networks are as neces-sary in the power industry as for the gener-ation and distribution of energy itself.Siemens offers a wide range of systemsand network elements specifically de-signed to solve communications problemsin this area.All systems and network elements areadapted to one another in such a way thatthe power industry’s future communica-tions requirements can be satisfied opti-mally both technically and economically.Siemens is offering advice, planning,production, delivery, installation, operationand training – one source for the customer.Providing expertise and commitment asthe complexity of the problem requires.Put your trust in the extensive know-howof our specialists and in the solidity of theinternationally proven Siemens communi-cations systems.

Flexible network configurationwith communications systems andnetwork elements

The gradual transition from analog to digitalinformation networks in the power industryand other privately operated networks re-quires a great variety of systems and net-work elements for widely differing uses.Prior to a decision as to which systemcould be used for the best technical andeconomical solution, it is first necessary toclarify such requirements as quantity ofspeech, data and teleprotection channelsto be transmitted, length of transmissionlink, existing transmission media, infra-structure, reliability, etc.Depending on those clarifications the mostcost-efficient and best technical solutioncan be chosen.

As shown in the block diagram below,we are offering systems and networkelements for analog transmission as wellas systems for digital transmission.The systems and network elementsshown in this survey of products havebeen specially developed for power in-dustry applications and therefore fulfillthe requirements with regard to qualityand workmanship as well as reliabilityand security.

All systems and network elements de-scribed meet the relevant internationalrecommendations and are designed, devel-oped and manufactured in accordance withthe requirenments of the quality systemsof DIN EN ISO 9001.

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A: Phase-to-groundcoupling

B: Phase-to-phasecoupling

C: Intersystemcoupling

PLC SystemAKE 100

CC or CVTLine trap

PLC SystemAKE 100

CC or CVTLine trap

PLC System

AKE 100

CC or CVTLine trap Line trap

CC orCVT

AKE 100HF hybrid

Coupling mode Costs

Minimum

Twice than A

Twice than A

A: Phase-to-ground coupling

B: Phase-to-phase coupling

C: Intersystem coupling

Attenuation Reliability

Greater than B&C

Minimum

Greater than B

Minimum

Greater than A

Maximum

1 Conduit with weather-resistantPLC cable screw connectionTerminal for coupling capacitorGrounding switch withswitch-rod eyeMain ground connectionExternal shock hazard protection1- or 2-pole coarse voltage arresterDrain and tuning coilIsolating capacitorIsolating transformerResistor for phase-to-phase coupling(balancing resistor)Gas-type surge arrester(optional extra)PLC cable terminalsHF hybrid transformer

23

456789

10

11

1213

Fig. 18: Coupling modes

Fig. 19: Comparison of the coupling modes

Fig.17: AKE 100 coupling unit with built-in HF hybrid transformer

Power Line Carrier (PLC)Communication

AKE 100 coupling unit

For carrier frequency communication viapower lines or via communication circuitssubject to interference from power lines,the high-frequency currents from and tothe PLC terminals must be fed into ortapped from the lines at chosen pointswithout the operating personnel or PLCterminals being exposed to a high-voltagehazard.The PLC terminals are connected to thepower line via coupling capacitors or viacapacitive voltage transformers and thecoupling unit. In order to prevent the PLCcurrents from flowing to the power switch-gear or in other undesired directions (e. g.spur lines), traps (coils) are used, which arerated for the operating and short-circuitcurrents of the power installation andwhich involve no significant loss for thepower distribution system.The AKE 100 coupling unit describedhere, together with a high-voltage couplingcapacitor, forms a high-pass filter for therequired carrier frequencies, whose lowercut-off frequency is determined by the rat-ing of coupling capacitor and the chosenmatching ratio.The AKE 100 coupling unit is supplied infour versions and is used for: Phase-to-ground

coupling to overhead power lines Phase-to-phase

coupling to overhead power lines Phase-to-ground

coupling to power cables Phase-to-phase coupling to power cables Intersystem coupling with two

phase-to-ground coupling unitsThe coupling units for phase-to-phasecoupling are adaptable for use as phase-to-ground coupling units. The versions forphase-to-ground coupling can be retrofittedfor phase-to-phase coupling or can be usedfor intersystem coupling.

13

1112

9

110

87

6

2

4 35

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Power Network Telecommunication

ESB 2000i power line carrier system

PAX/PABX

Communi-cationsysteme. g. Hicom

PAX/PABX

2/4-wireE&M

Protectionrelay

Data

Powersystemcontrol

LAN

V.24/V.28

MUX

BMX

DEE

So

Distance protection

Data V.28 up to2400 Bd or via MODEM

SDHPDH

Data V.28up to 2400 Bd

SWT 2000 F6

Modem, ≤ 19,2 kbits/s

FWT 2000i

Line trap

Couplingcapacitor

Couplingunit

ESB 2000i

Service PC

64 kbit/s

64 kbit/s

64 kbit/s

Remotesubscriber

Servicetelephone

Fig. 20: ESB 2000i power line carrier system

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Power Network Telecommunication

---

---Digitalsignalprocessing

Interface-modules

Modulation

Demodulation

Poweramplifier

Receiveselection

Central control

Fig. 21: ESB 2000i functional units

Fig. 22: ESB 2000i PLC System with 40 W amplifier

ESB 2000i power line carrier system

Modern PLC systems must not only takeinto account the specific characteristics ofthe high-voltage line but must guaranteefirst and foremost that they will be eco-nomically and technically usable in futuredigital networks.The ESB 2000i digital PLC system meetsthese requirements through Use of state-of-the-art digital signal pro-

cessor technology (DSP) User-oriented service features, e. g.

– automatic line equalization– automatic frequency control (AFC)– remote supervision/maintenance– programming of parameters by PC

Integration of data transmission systems(channel circuits KS 2000 and KS 2000i)

Digital interfaces for transmission upto 64 kbit/s

Use of the ESB 2000i PLC system alsoenables the full advantages of digital trans-mission to be exploited when employingthe high-voltage line as a transmission me-dium. The ESB 2000i PLC system also sat-isfies economic requirements such as lowinvestment costs, reduction of expenditurefor maintenance and service and technicalrequirements with respect to security,availability and reliability.

Application

The ESB 2000i PLC system permits carriertransmission of speech, fax, data, tele-control and teleprotection signals in thefrequency range from 24 kHz to 500 kHzvia: Overhead power lines and Cablesin high- and medium-voltage systems.The information is transmitted using thesingle-sideband (SSB) method with sup-pressed carrier. This method permits: Large ranges due to maximum utiliza-

tion of the transmitter energy for signaltransmission

The smallest possible bandwidth andtherefore optimum utilization of thespectrum space of the frequency rangepermitted for the transmission

Improved privacy due to carriersuppression

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Fig. 24: Transmission rates of the digital interface of the PLC system according to the available bandwidth

Fig. 23: Basic diagram of the ESB 2000i PLC System for digital transmission

ESB 2000i

DigitalinterfaceX.21/V.11orG 703.1orV.28

SSB-modulator/demodula-tor

PLC-line-unit

Service channel

Servicetelephone

Service PCnetwork management

Digitaltrans-missionfrom 1.2to 64 kbit/s

HF-bandwidth2.5 to8 kHz

Central processor

19.2 kbit/s

32 kbit/s

40 kbit/s

64 kbit/s

Bandwidth 2.5 kHz

Bandwidth 4 (3.75) kHz

Bandwidth 5 kHz

Bandwidth 8 (7.5) kHz

Note:A service channel forremote maintenance andfor service telephone isprovided in addition to theabove nominal bit rates.

Digital interface of the ESB 2000iPLC System

The ESB 2000i PLC system with ITU-Tstandardized digital interface for trans-mission rates up to 64 kbit/s significantlyincreases the possible applications.By using external multiplex systemsproviding ITU-T standardized interfacesX.21/V.11 or G 703.1, it is possible toadapt the ESB 2000i PLC system moreflexibly to the number of transmissionchannels and the various interfaces for thedigital transmission of speech and data.

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Power Network Telecommunication

Fig. 25: SWT 2000 F6 teleprotection signal transmission system (stand-alone version)

IF 4

IF 4M

CLE

OMA

Distanceprotection Electrical line

connection

Annunciations

PUOptical lineconnection

PS

Alarms24 ... 60 V dc110/220 V dc/acService PC

SWT 2000 F6 protection signalingsystem for analog transmission links

The task of power system protectionequipment in the event of faults in high-voltage installations is to selectively dis-connect the defective part of the systemwithin the shortest possible time. In viewof constantly increasing power plant capac-ities and the ever closer meshing of high-voltage networks, superlative demands areplaced on power network protection sys-tems in terms of reliability and availability.Network protection systems featuring ab-solute selectivity therefore need secureand high-speed transmission systems forthe exchange of information between theindividual substations.The SWT 2000 system for transmission ofprotection commands provides optimumsecurity and reliability while simultaneouslyoffering the highest possible transmissiontime.

Application

The SWT 2000 F6 system is for fast andreliable transmission of one or more pro-tection commands and / or special switch-ing functions in power networks. Protection

– Protection commands can be trans-mitted for the protection of twothree-phase systems or one three-phase system with individual-phaseprotection

– High-voltage circuit-breakers can beactuated either in conjunction withselective protection relays or directly

Special switching functions– When the system is used for special

switching functions, it is possible totransmit four signals. Each signal isassigned a priority.

Transmission paths

Depending on the type of supply network,the following transmission paths can beutilized: High- and medium-voltage overhead

lines High- and medium-voltage cables Aerial and buried cables Radio relay links

Fig. 26: Block diagram of the SWT 2000 F6

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Power Network Telecommunication

Fig. 27: FWT 2000i telecontrol and data transmission system

FWT 2000i telecontrol and data trans-mission system for analog/digital trans-mission links

In all areas related to the telemonitoring ofsystems, automation technology and thecontrol of decentralized equipment, it mustbe possible to transmit signals and meas-ured values economically and reliably.The new FWT 2000i System for telecontroland data transmission can be flexibly usedto perform the various transmission tasksinvolved in system management not onlyin public utility companies, railway compa-nies and refineries, but also in the areas ofenvironmental protection and civil defense,as well as in hydrographic and meteorolog-ical services.The following characteristics of theFWT 2000i system make it suitable formeeting users’ special requirements: Safe operating method around

high-voltage systems High degree of reliability and safety Short process cycle times Easy handling Economical useThe FWT 2000i system offers a variety ofmodules for the widest possible range oftransmission tasks. Thanks to the unlimit-ed equipping options of the frame, virtuallyall system variants necessary for operationcan be implemented on a customer-spe-cific basis.

Universal for all frequenciesand transmission rates up to 2400 Bd

The KS 2000i channel unit accommodatesa transmitter and receiver assembly. Alltransmission rates from 50 to 2400 Bd canbe set in all frequencies within the 30-Hzraster, including in the frequency raster toITU-T.

Transmission in the superimposedfrequency band

The FWT 2000i System permits transmis-sion in the frequency range from 300 to7200 Hz.

Modularity

The modularity of the KS 2000i channelunit is typified by its integration in variousother systems, i.e. its use is not limited tothe FWT 2000i system.For instance, the channel unit can beintegrated in: The ESB 2000i PLC system The SWT 2000 F6 protection signaling

system Telecontrol systems.

Transmitter and receiveras separate modules

Separate modules that function only asa receiver or only as a transmitter are avail-able for this operating method.

Flexibility

By using additional modules the systemcan be extended for alternative pathswitching or transmission of the controlfrequencies of a multistation controlsystem.

Fast and easy fault localization

A variety of supervisory facilities andautomatic fault signaling systems ensureoptimum operation and fault-free trans-mission of data.

Transmission media

Suitable transmission media are under-ground cables, grounding conductor aerialcables, aerial cables on crossarms ofpower line towers, PLC/carrier frequencychannels via power lines, carrier links,PCM links and Telecom-owned currentpaths.The overall concept of the FWT 2000i sys-tem meets the stringent demands placedon power supply and distribution networks.The FWT 2000i meets the special require-ments with regard to reliable operation andelectromagnetic compatibility.

Additional benefits

In addition to the system features, theFWT 2000i system provides all users withthe cost-effective and technical benefitsexpected and required when this systemis used. Economical stocking of spare parts

is possible since, from now on, onlyone module is needed for all rates andfrequencies.

The system can be placed in servicequickly and easily thanks to automaticlevel adjustment and automatic com-pensation of distortion.

The use of the state-of-the-art digitalprocessors and components ensuresthat the system will have a long servicelife and a high rate of availability.

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Power Network Telecommunication

Fig. 28: KS 2000i channel unit

KS 2000i channel unit

The new KS 2000i channel unit is suitablefor transmission of asynchronous data onanalog media and such forms a completeand versatile VFT modem.Both transmitter and receiver are acco-modated on only one plug-in card eitherto be used as stand-alone unit (seperateframe) or to be integrated in ESB 2000iPLC terminal or in remote terminal unit(RTU).Frequency shift as well as transmissionspeed are independently adjustable.With a maximum transmission speed ofup to 2400 Bd the VFT channel approachesapplications traditionally realized with high-speed modems only.Beside others the KS 2000i channel unitprovides the following features: High reliability High flexibility Easy detection of faults Excellent transmission characteristics

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Power Network Telecommunication

Fiber optic communication

4 x 2 Mbit/s

The LFH 2000 systemTelecommunication requirements in power utilities

34 Mbit/s 2 Mbit/s

34 Mbit/s

4 x 2 Mbit/s

2 Mbit/s

OLE 2

SWT

MUX

ODF

MDF

PABX LSA

4 x 2 Mbit/s 4 x 2 Mbit/s 4 x 2 Mbit/s34 Mbit/s

2 Mbit/s

34Mbit/s

OLE 34

OLE 34

MUX/CC

DSMX

OLE 8

MUX/CC

SWT

ODF

ODF

MDF

PABX PABX

Energymanagement

system

Communi-cations networkmanagement center

LWL

Office

Communications room

LAN

Protection

Electrical link (CU)Fiber-optic link

Fig. 29: The LFH 2000 fiber optic transmission system – Telecommunication requirements in power utilities

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DPU IF 4orOM

IF 4orOM

PS

Alarmandeventre-corder

OFC(Fiber-opticcables)

Distanceprotectionordigital currentcomparison

ServicetelephoneST-A orST-B

AUX orAUX 1+1 orAUX BUS

Tele-controlsystem

PABX

TRCV 2 orTRCV 8 orTRCV 34

LWL

TRCV 2 orTRCV 8 orTRCV 34

LWL

DPU

IF4

OM

PS

ST-A

ST-B

AUX

AUX 1+1

AUXBUS

TRCV

LWL

Digital processor unit

Interface module fordistance protection relays

Optomodule for connectionof digital current comparisonprotection system

Power supply

Module for service tele-phone with DTMF signaling

Module for nondialingservice telephone

Service channel unit

Service channel unit withprotection switching

Bus channel unit

Optical transceiver

Optical fiber

Power Network Telecommunication

Fig. 30: LFH 2000 fiber optic transmission system

LFH 2000 fiber optictransmission system

Flexible network configuration and futurecommunications requirements of privatenetwork users, such as power companies,call for universal network elements fortransmission in digital communications net-works.LFH 2000 has been designed and devel-oped on the basis of extensive experiencegained with fiber optic transmission sys-tems in public networks and transmissionelements specially developed for such sys-tems. It was tailored to the needs of pow-er companies and other private networkusers.In its basic version LFH 2000 consists ofa 19-inch subrack equipped with an opticalline terminating unit TRCV2 and a servicechannel module. Even in its simplest con-figuration, LFH 2000 offers various typesof interfaces for the transmission ofspeech and data channels such as: Line interfaces up to 34 Mbit/s So-interface for networking digital

telephone systems (e.g. Hicom) QD 2-interface for network manage-

ment

The incorporation of the SWT 2000 D digit-al protection data system provides addi-tional functions required for most applica-tions in power companies.The basic version can be optionallyequipped with service telephone units,optical line terminating units with highertransmission speeds or with other servicechannel modules so that the system canbe conveniently adapted to the individualtransmission requirements.Further network elements may be con-nected to LFH 2000 via internationallystandardized interfaces if the number ofrequired channels and the types of inter-faces, i.e. the capacity of the system,have to be extended.Depending on the number and type of thetransmission interfaces required, LFH 2000can be expanded by connecting flexiblemultiplex systems.

LFH 2000 is provided with internationallystandardized interfaces so that transmis-sion systems of other manufacturerswhich are also equipped with internation-ally standardized interfaces can communi-cate with LFH 2000. This also makes itpossible to combine LFH 2000 with digitaltransmission system of other manufactur-ers.The incorporation of LFH 2000 with theexpansion element e.g. flexible multiplexsystem into a network hierarchy withdiffering transmission rates as currentlyplanned and implemented by private net-work operates can be easily achievedusing the compatible network elementsavailable today.The call for a user-friendly network man-agement can be fulfilled by adding therequired hardware and software.LFH 2000 meets the requirements of thepower companies and private networkoperators due to its flexibility, availabilityof internationally standardized interfacesand compatibility with regard to its incor-poration into existing private networks.

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Power Network Telecommunication

Fig. 32: Block diagramm SWT 2000 D

1300 nm1500 nm

IF 4

Alarms24 ... 60 V dc110/220 V dc/acService PC

Digitallongitudinaldifferentialprotection(7SD51)

Distanceprotection

O.F.820 nm

n x 64 kbit/s

X.21/V.11G.703

TRCV

OM

O.F.

O.F.

Alter-nativeroute

PCM 2 Mbit/s 40/60 V dc

IF 4

PS

DPU

SWT 2000 D protection signalingsystem for digital communication links

In comparison with analog protectionsignaling the use of digital transmissionlinks provide noise-free communication.Switching operations, atmospheric condi-tions and other sources of interferenceon power lines do not impair secure andreliable transmission of protection signals.The SWT 2000 D system for the transmis-sion of protection signals on digital trans-mission links, mainly fiber optics, providesoptimum security and reliability whilesimultaneously offering the quickest possi-ble transmission speed.

Uses

SWT 2000 D system is used for fast andsecure transmission of one or several in-dependent binary signals for protectionand special switching functions in powernetworks and/or the transmission of serialprotection data.The system is avaliable in versions for thetransmission of protection data on sepa-rate fibers and on 64 kbit/s PCM channels.As an optimized solution between thesetwo possibilities, the system offers trans-mission of the protection data in the serv-ice channel of an optical line terminationsystem (e. g. OLTS, OLTE 8) which en-sures maximum independence of the pro-tection data from voice and data transmis-sion despite the common use of fibers infiber optic cables.

Applications

All types of distance protection(permissive tripping, blocking, etc.)

Direct transfer tripping Special switching functions Digital current comparison protection

(differential protection) with optical serialinterface ≤ 19.2 kBd (e. g. with 7SD511).

Features

Up to 8 parallel (binary) commands,bi-directional

Up to 2 serial protection data,bi-directional

Simultaneous transmission of serialprotection data and up to 4 binary pro-tection commands

High-performance microcontroller Permanent self-supervision Automatic loop testing Event recorder with real-time clock

(readable via hand-held terminal or PC).

Fig. 31: SWT 2000 D for flush panel mounting with integrated TRCV2 optical line equipment

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Power Network Telecommunication

Flexible Multiplexer (FMX)

Depending on the number and type ofthe transmission interfaces required, theLFH 2000 optical fiber transmission systemcan be extended by connecting the flexiblemultiplex system (FMX).The FMX multiplexer is based on a flexibledesign which is considerably different fromnormal PCM systems. For terminal oper-ation, it contains a central unit CU, CUADor CUDI unit and, for branch operation, aCUDI central unit as well as the withdraw-able channels.Thanks to the software-controlled configu-ration and parametrization of the multiplex-ers they can be integrated quickly andeasily into the network.The 19'' inset has sockets for two centralunits (CU, CUAD, CUDI), twelve channelunits, a supervision unit and two powersupply units.

User Interfaces(see Fig. 33)

The LFH 2000 System – overview(see Fig. 34 on page 7/23)

Fig. 33: FMX interfaces

ISDN Basic access unit I4SO 4 x

I4UK4 NTPI4UK4 LTP 4 x

DSC6-nx64G 6 x

DSC2-nx64 2 x

DSC8x21 8 x

DSC4V35 or DSC4V36 4 x

CU or CUDI or CUAD

DSC8V24 8 x

DSC104CO 10 x

SLB62 6 x

SLX62 6 x

SUB62 6 x

SEM106 or SEM108 10 x

CU or CUDI or CUAD

S0 interface

UK0 interface, 2B1Q or4B3T, NT-mode or LT-mode

n x 64 kbit /s G.703 codirectional orn x 64 kbit /s G.703 contradirectionalor centralized clock

X.21or V.24/V.28 bis(switchable)

X.21/V.11 ≤ 64 kbit/s

V.35 ≤ 64 kbit/s orV.36 ≤ 64 kbit/s

Central unit, standard,or central unit for add/drop operationor central unit for ADPCM

V.24/V.28 < 64 kbit/s

64 kbit /s G.703 co-directional

2-wire LB subscriber

Exchange, 2-wire

Subscriber, 2-wire

2-wire NF and 2 E&M or4-wire NF and 2 E&M

Central unit, standard,or central unit for add/drop operationor central unit for ADPCM

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TRCV SMUQ Service channel MUX Cross connect

V.11

Speechfour-wire+ E&M

V.28

ServicetelephoneSpeech,two-wire

V.11

Protection

Speechfour-wire+ E&M

Data RTUV.28

PABX

PLCn x 64 kbit/s

The LFH 2000 System – Overview

EMOS QD2 Networkmanagement system

EMS Energymanagement system

SDH 155/622Mbit/s

Remotesubscriber

External and/orinternal exchange

Substationcontrol andprotectionsystem

Data interfacese.g. X.21,V.24, LAN

Data and voiceof PLC links

Distance protectionor digital currentcomparisonprotection

34Mbit/s

SDH155 Mbit/s2,5 Gbit/s

4 x 2 Mbit/s

Protection

PABX

RTU

Data

4 x 2 Mbit/s

34Mbit/s

4 x 2 Mbit/s

2 Mbit/s

34 Mbit/s

34 Mbit/s 34 Mbit/s

2 Mbit/s

4 x 2Mbit/s

2 Mbit/s

2 Mbit/s

4 x 2Mbit/s

Fig. 34: The LFH 2000 System – Overview

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Conclusion

The described digital and analog networkelements are, of course, only a small se-lection from the multitude of network ele-ments which Siemens has on hand for theimplementation of transmission networks.We have focused on those products whichhave been specifically developed for thetransmission of information in power utili-ties and which are indispensable for theoperation of such companies.It has also been our intention to show theuses for our products and how they can beintegrated in transmission networks withvarying network elements and networkconfigurations.The great variety of products in the fieldof digital transmission systems and thedifferent requirements of our customerswith regard to the implementation of digit-al transmission networks make customer-specific planning, advice and selection ofnetwork elements an absolute necessity.Detailed descriptions of all products canbe sent to you upon request.

For further information please contact:

Fax: ++49- 89-722-2 44 53 or++49- 89-722-4 19 82

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Energy Metering

Contents Page

General 8/2

Areas of application 8/2–8/4

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Energy Metering

Areas of application:

Domestic

Fig. 2

Single-phasemeasurement ofcurrent consumptionin low-voltage net-works with high andlow tariffs

High measuringaccuracy and stabilityin extended use(class 2)

Fig. 1

3-phase measure-ment of active andreactive energy con-sumption in 3- and4-wire systems

High measuring ac-curacy and stabilityin extented use(class 2)

1 and 2 tariff appli-cations

Direct connectionor connection viacurrent transformer

Fig. 4Fig. 3

Fig. 3: Static 3-phase meter 7EC49Fig. 4: Ferraris 3-phase meter 7CA54

Fig. 1: Adaptive meter (1-phase)Fig. 2: Ferraris single-phase meter

General

Energy meters are used for measuring theconsumption of electricity, gas, heat andwater for purposes of billing. In this regard,modern energy meters should be able tohandle differing regional tariff structures aswell as complex tariffs in industrial applica-tions. The meters must also comply to thegeneral regulations for measuring instru-ments laid down in OIML D11.

Specifications

The following international specificationslay down the requirements for the differ-ent meters in terms of measuring accura-cy, robustness, electromagnetic tolerance,burden, etc: IEC 1036: Electronic current meters with

measuring accuracy in class 1 and 2 IEC 687: Electronic precision meters,

class 0.5 s and 0.2 s IEC 521: Ferraris meters with measuring

accuracy in class 1 and 2 OIML R6: Static gas meters IEC 1107: Specification of optical

interfaces EN 50081 and EN 50082:

Specification of interferencerobustness and interference radiation

Siemens energy meters comply with allthese requirements. Stringent quality con-trol ensures functionality in all our prod-ucts.

Certifications

High product and service quality is ensuredby the implementation of internationallyaccepted procedures. An independant in-stitute has confirmed this by issuing theISO 9001 certificate.

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Energy Metering

Areas of application:

Domestic

Wear-free flowmeasurementthrough the use ofultrasonic technologyby the static heatmeter

Energy measure-ment in optimalrange (class C)

Prepaymentelectricity meteringin class 2

Single-phase,2-phase and3-phase meters

Keypad-based credittransfer

Programmablepower limiting

Intelligent overloadprotection

Fully integrated,flexible credit vend-ing systems

Current capabilityup to 80 A

Commerce and industry

Fig. 7: 7E.6 – One meter for all special tariffs

Measurement ofactive energy in twodirections with accu-racy class 1 and 2

4 tariffs each fordemand and energyconsumption

One tariffless, sum-total energy register

Integrated real-time clock for tariffswitching

Integrated ripplecontrol receiver(RCR)

Storage of up to15 previous energy/demand values

Maximum demand inall tariff periods

Storage of detailedload profile

Fig. 5: Sonic heat meter 2WR4

Fig. 6: Cashpower 2000. The keypad prepayment electricity metering system that uses no cards, tokens or coins

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Large-scale industry

Energy Metering

Areas of application:

Measurement of active and reactiveconsumption in both directions

Individual metering of all 4 quadrants 4 different tariffs for each

measurement parameter Direct connection or connection

via current transformers Reduced wiring requirements Apparent power calculation

Bulk-energy transfer stations

All of the abovefunctions of the 7E.6in the accuracy class0.5 s and 0.2 s

As build-in and plug-in meter

Fig. 9: High-precision energy meterFig. 8: The 7E.6 is able to replace a complete set ofmeters – at lower connection and operational costs

Siemens Energy Meter Management System SEMMSfor power supply and distribution companies and for industry

Interchange pointLoad management

Check meterEnergy cost allocation

Industry

SEMMS

Industry-standardfunctionmeter

Utilitybillingmeter

Specialtariff-ratecustomer

Tariff-rate customer

Utility

Siemens metering technology alsocontains a wide range ofinstruments for communication,registration and remote interrogation(such as Ripple Control Receiver)

MeterSet ist object-oriented.This means that it can be connected notonly to Siemens meters, but to allforeign manufacturers´ meters well.SEMMS + MeterSet allows consistentmanagement of meter information.All meter information is transferreddirectly from MeterSet into SEMMS,eliminating transfer errors and increasingoperational security.

MeterSet:The software for: configuration clarification interrogation

M

MeterSet

Fig. 10: Siemens Energy Meter Management: With SEMMS you can handle the future

SEMMS interrogates all models ofmeters installed by power supply anddistribution companies, eliminatingmanual meter reading, allowing fasterbilling and supporting simplified metermaintenance

SEMMS interrogates all kinds of metersin industrial applications automatically,helping to assign and optimize costs

For further information please contact:

Fax: ++49-911- 4 33 -80 37

Fig. 11

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System Planning

Contents Page

Overall Solutions forElectrical Power Supply 10/2–10/6

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Fig. 1: Tasks, Solutions and Results

System Planning

Overall Solutions forElectrical Power Supply

Integral power system solutions are farmore than just a combination of switch-gear, transformers, lines or cables, togeth-er with equipment for protection, supervi-sion, control, communication and someothers more. Of crucial importance for thequality of power transmission and distribu-tion is the integration of different compo-nents in an optimized overall solution interms of:

System design, creative system layout,based on the load center requirementsand the geographical situation

Component layout, according to tech-nical and economical assumptions andstandards

Operation performance, analyzing andsimulation of system behavior undernormal and fault conditions

Siemens System Planning

Whether a new system has to be plannedor an existing system extended or updat-ed, whether normal or abnormal systembehavior has to be analyzed or a postfault

clarification done, the Planning Division,certified to DIN ISO 9001, is competentand has the know-how needed to findthe right answer. The investigations coverall voltage levels, from high voltage to lowvoltage, and comprise system studiesfor long-distance transmission systemsand urban power networks, as well as forparticular distribution systems in industrialplants and large-scale installation for build-ing centers in close cooperation with theircustomers and other Siemens Groups(Fig. 1).

Voltage qualitySystem perturbationsNeutral groundingFault clearingOverloadOvervoltageAsymmetryTransient phenomenaReactive power balancePower-station reserve

Operation performance

GeneratorTransformerCircuit breakerOverhead lineCableCompensationequipmentEquipment forneutral groundingProtection equipmentHVDCFACTSControl equipmentGrounding

Component layout

Load developmentCable restructuringUpgrading installationsSelecting voltage levelsSystem takeoverDefining new transfomersubstationsSystem interconnectionConnecting power stations

Tasks Solutions Results

System design System analysis,system documentation

System calculations,load-flow and short-circuit

Planning and calculating AC andDC transmission

Determining economic alternatives

Specifying the configuration ofthe system

Design of electrical installations

Design of protection system,selecting equipment, selectivityand excitation tests

Testing and customer acceptanceinspection of protection equipment

Simulation of complete systemand secondary equipment

Switching operations, layout ofovervoltage protection system,insulation coordination

Analysis of harmonics, layout offilter circuits, closed-loopand open-loop control circuitsfor power converters

Simulation of system dynamics

Layout of power electronicequipment (FACTS)

Method of neutral grounding

Reliability analysis

Earthing arrangement andmeasurement

Investigation of interference

Propagation of ripple-control signals

Economical solution of distributionand transmission systems

Simple and reliable operation

Minimization of losses

Reduction of the effects,extent and duration of faults

Priorities in system extensionReplacement of old installations,reconstruction, extension ornew constructions

Extensively standardizedsystem components

Compliance with specifiedperformance values

Safety for persons

Economical altenatives

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Siemens Power Engineering Guide · Transmission & Distribution 10/3

Powergeneration

Transmission systemup to 550 kV with HV/HV

bulk substations

Subtransmission system up to 145 kVwith HV/MV main substations

Medium-voltage distribution system up to 36 kVMV/LV transformer public substationsand consumer connection substations

Low-voltage distribution system up to 1 kV.Public supply system or internal installation system

Consumer power application industry, commerce, trade,public services, private sector

Distribution function

Transmission function

influence or faults of components cannever be avoided completely, it has to beassured that the time of interruption isminimized. This is a question of reserve inthe system. Different degrees of reservecan be provided depending on the require-ments.

System Planning

Fig. 2: The Pyramid of Power Supply

The Power Supply System

The power supply system is like a pyramidbased on the requirements of consumersand the applications and topped by thepower generation (Fig. 2).The power system is basically tailored tothe needs of consumers. Main characteris-tics are the wide range of power require-ments for the individual consumers froma few kW to several MW, the high numberof similar network elements, and the wide-spread supply areas. These characteristicsare the reason for the comparatively highspecific costs of the distribution system.Thus, standardization of equipment, useof maintenancefree components, and ut-most simplification of system configurationhave to be considered for an economicalsystem layout.The load situation at the LV level deter-mines the most suitable location of publicMV/LV substations and consumer connec-tion stations and, to a high degree, theelectrical and geographical configuration ofthe superposed medium-voltage distribu-tion network as well.HV/MV main substations feeding themedium-voltage distribution system shouldbe located as close as possible to the loadcenters of the medium-voltage distributionareas. The subtransmission system feed-ing the main substations is configuredaccording on their location and the locationof the bulk power substations of the trans-mission system. The largely interconnect-ed transmission system, e.g. up to 550 kV,balances the daily and seasonal differencesbetween load requirements and differentavailable generation sources.

Basic conditions for system design

Industry, trade and commerce as well aspublic services (transportation and commu-nication systems), but not forgetting theprivate sector (households), depend highlyupon a reliable and adequate energy sup-ply of high quality at utmost economicalconditions. In order to achieve these aims,several aspects must be considered(Fig. 3). International and national stand-ards are the basic fundamentals for sys-tem design. The choice of system voltagelevels and steps is of decisive importancefor the economical design and operation.Reliability requires adequate dimensioningof components with regard to current-carrying capacity, short-circuit stress andother relevant parameters. Although inter-ruptions in supply due to environmental

Fig. 3: Aspects of system planning

Loaddevelopment

Systemarchitecture

Networkcalculation

Protectionanalysis

Protectioncoordination

Investmentplanning

Networkrepresentation

Systemanalysis

Energy Supply”reliable and economical“

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System Planning

System Planning, a complex activity

System planning and configuration iscomparable with architectural work, findingthe best technical and economical solution.System planning has therefore to startwith a thorough task definition and systemanalysis of the present status, based onthe given quality requirements. Alternativesystem concepts (system architecture)in several expansion stages ensure thedynamic development of the system,adapted to structure and load requirementsof the subposed voltage level. Componentdesign and the infeed from the super-posed voltage level has to be consideredas well. Technical calculations and eco-nomic investigations complete the plan-ning work and are essential for the choiceof the final solution (Fig. 4).

Load Development

The load analysis and estimation in thedistribution system are always a matterof distributed loads in an certain area.In urban and rural areas, natural borders –such as rivers, railway lines or major roadsand parks or woodlands allows the wholesupply district to be subdivided into anumber of subareas.In large commercial complexes, such asairports or university and hospital centersas well as in industrial areas, the load esti-mation is based on the individual buildingsand workshops.Different methods are used for load esti-mation, such as annual growth rates forexisting public areas, load density for newdeveloping settlements, installed capacityand simultaneity factor for commercial andindustrial supply.

Distribution

Network configuration for power distribu-tion is a matter of visualization and will notbe executed successfully without the geo-graphical information of load and sourcelocation for public supply and industrial orlarge building supply as well. Thus, eachdistribution system must be planned indi-vidually. But, for the basic design, somestandard configuration has proved optimalin terms of Simple configuration Easy operation and Economical installation

Low-voltage systems are usually operatedas open radial networks. Industrial systemsin particular contain facilities for transfer tostandby. Meshed operation is usually onlyintended for special load situations, suchas single loads with great fluctuations orwelding systems.Medium-voltage systems are primarilygoverned in their configuration by the loca-tions of the system and consumer stationsto be supplied.The most suitable arrangements for publicsupplies are open-ring systems or line sys-tems to a remote substation.For industrial and building power supplysystems, the higher load densities resultin shorter distances between substations.This leads for reasons of economy to thespot system with radial-operated trans-formers.Industrial power supply differ from publicnetworks inasmuch as they have a highproportion of motor loads and often in-plant generation. Depending on the capaci-ty, units will be connected to normal low-voltage level, intermediate low-voltagelevel or medium-voltage.The technically and economically optimalconfiguration of distribution systems callsfor wide-ranging practical experience froma large number of different projects andmust determine switchgear configurationas well.

Transmission

The design of transmission systems is toa great extent individually tailored to thelocation of generating plants and bulksubstations feeding the subtransmissionsystem. Planning of high-voltage intercon-nected networks and transmission net-works is a complex matter since they areoperating over several different voltage lev-els and mostly meshed systems are used.This and the regional and seasonal differ-ence of generation input and consumerdemand as well as the many different sizeof lines, cables and transformers, makeload-flow distribution complicated andrequire detailed calculations of systembehavior and the operating conditions ofpower generation during planning work.As well as the actual planning, it includesnumerous investigations, for instance, todetermine the switchgear configurationand various equipment. This also entailsdetailed studies of the reactive power,voltage stability, insulation coordination,and testing of the dynamic and transientbehavior in the network resulting fromfaults. Connection of neighboring transmis-

sion systems via AC/DC coupling, the im-plementation of HVDC transmission or su-perposing a new voltage level needs com-prehensive planning and investigation work(Fig. 5).

Tools

Beside the great experience and know-how Siemens Power System Planningapplies powerful tools to assist the engi-neers and their highly responsible work.

SINCAL

(Siemens Networ Calculation) for analysisand planning purposes. Any size of sys-tems with line and cable routing are simu-lated, displayed and evaluated with theSINCAL program system. With the help ofan integrated database and easy-to-usegraphics system, schematic and topologi-cal equivalent systems can be digitized orconverted to other systems.

NETOMAC

(Network Torsion Machine Control) is aprogram for simulation and optimizationof electrical systems which consist of net-work, machines and closed-loop and open-loop control equipment. Two modes oftime simulation, instantaneous value modeand stability mode can be used separatelyor in combination. The program serves for Simulation of electromechanical

and magnetic phenomena Special load-flow calculations Frequency-range analysis Analysis of eigenvalues Simulation of torsional systems Parameter identification Reduction of passive systems Optimization

DISTAL

(Distance Protection Grading) calculatesthe setting values of the impedance forthe three steps and for the overreachzones (automatic reclosing and signal com-parison) of distance protection equipmentin any kind of meshed network.

CUSS

(Computer-aided Protective Grading) indi-cates grading paths and grading diagrams,checks the interaction of the current-timecharacteristics with regard to selectivityand generates setting tables for the pro-tection equipment.

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System Planning

DISCHU

simulation and testing of numerical pro-tection relays.

PRIMUS

works out the most suitable voltage fora DC transmission project together withthe most important electrical data andthe costs.

SECOND

is used to calculate the electrical character-istics and costs of a given AC transmissionproject.

FELD

permits calculation of electrical and mag-netic fields which occur during operationand fault conditions in the environment ofone-, two- and three-phase systems (e.g.overhead lines and railway lines) in a two-dimensional way.

LEIKA

permits calculation of the electrical charac-teristics of overhead lines and cables.

TERRA

is for calculating the potential fields ofgrounding installations.

KABEIN

is used for calculating the inductive inter-ference to which telecommunication linesand pipelines are subjected by the operat-ing currents or fault currents of high-volt-age overhead lines or cables at any levelsof exposure.

SUNICO

calculates how to make optimum use ofpower stations. It indicates the best choicefrom among the available power units andthe best way of dividing up the systemload among the individual units used.

HADICA

is used for calculating harmonic voltagesand currents in electrical systems.

ACFilt

(Filter-circuit design) is for dealing effi-ciently with harmonic compensation.

Fig. 5: Planning tasks for interconnected transmission system

Fig. 4: Steps for network planning

Weak pointdeterminationImmediate action

Task definitions,System analysis ofpresent status

Technical standards,Reliability require-ments

Technical/economicalcalculations andevaluations

System architectureAlternative systemconcepts for stages

Expansion projectLoad development

Superposedvoltage levelInfeed

Component designProtectivecoordinationMethod of neutralgrounding

Subposed voltage levelLoad structure

Proposal forsystem layout

Existing systemPlanned

Tasks

Load development andpower plant schedulesVoltage steps andtransformer substationsizesInstallation typeand configurationVoltage-controland reactive-powercompensationLoad-flow controland stability criteriaDynamic andtransient behaviorSystem management(normal and faulted)

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System Planning

Advanced AC/DC real-time simulation

The development and testing of measur-ing, protection and control equipment oflarge power supply installations need totake place under real system conditions.Siemens System Planning utilize a real-time simulator based on a modular princi-ple so that different layouts and structuresof the projects can be dealt with flexibly.In the simulator, there are 6 test stationswhich enable parallel work to be carriedout. Four of them are specially designedfor testing large power converters such asHVDC and FACTS units. Station 5 has spe-cial interfaces for testing system protec-tion schemes. Custom power station 6 isused for Advanced Power Electronic Appli-cations such as SIPCON (Siemens PowerConditioner). In addition to the classic type

of simulator with physical elements, real-time injection of transient signals from dig-ital simulations is also possible, e.g. withNETOMAC or RTDS, so that computer andanalog simulation complement each other.

Measurements, Instruction and Training

Sometimes only field measurements canprovide an accurate picture of the actualsituation and will be conducted for acquisi-tion of data, clarification of disturbancesand verification of functions.Also, instruction and training matched tothe particular needs of the customers,acquainting them with installations or alsoprocedures for use of software and meth-ods of planning are important aspects,provided by Siemens System Planning.

For further information please contact:

Fax: ++ 49 - 91 31-73 44 45

=1 =1

∆u, ∆f, ∆φGPower Generation

AC/DC Systems

6 Test Stations

Simulator Interfaces

Real-Time ComputerSimulation

Signal Generation andRecording

Measuring, Protectionand Control

Positive and ZeroSequence Components

Digital SequenceConrollers

Playback ComputerSimulation

HVDC and FACTS

1 … 4

Custom Power

6

5

Protection

Signal Acquisition System

NETOMAC, EMTDC, EMTPRTDS

Fig. 6: Advanced AC/DC Real-Time Simulator facilities

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High-Voltage Power Transmission Systems

Contents Page

High-voltage PowerTransmission Systems 11/2–11/4

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High-Voltage Power Transmission Systems

Introduction

The supply of power means more than justthe combination of individual components.Particularly in countries where demand forpower is growing at an above-average rate,there are large-scale projects under way,e.g. transmission systems or industrialcomplexes (Fig. 1).Setting up such large-scale projects callsfor an expert partner, capable of diligentlyanalysing demand and of planning theproject integrally, taking all marginal condi-tions into account. This means a compe-tent partner who produces top-quality com-ponents both for power transmission andfor system management tasks. Such apartner must also ensure that the systemswill be properly installed.

Experienced project management –the way to the successful project

With all key technologies in house,Siemens can provide turnkey solutions forthe individual demands in the field of pow-er transmission and distribution.The scope of supply includes all compo-nents from the generator terminals, via ACor DC transmission and the high-voltagegrid to the HV, MV and LV distribution sys-tem going down to the individual custom-ers.The benefit of the turnkey projects are: All project coordination is in one hand

and The interfaces between customer and

supplier are minimized The turnkey responsibility of Siemens

reduces the project risk for the customer.In close cooperation with the customer,the task definition for the scheduledproject is drawn up, and all marginal condi-tions clarified (Fig. 2).

Fig. 1

Fig. 2: Scope of supply and services

PTS and componentsDevelopmentand production of keycomponents

Supply, manufacture

Quality assurancePersonnel trainingMaintenance

Services, e.g.

Project developmentFeasibility studiesFinancial engineeringPartner & shareholder

BOO/BOT projects

Planning, projectengineeringConsultancyCoordinationStudies, analyses

Planning, consultancyOverall projectmanagementOn-site implementationOn-site supervision

Site management,installation &commissioning

Consortium leadershipConsortium memberin the construction ofPTS

Consortium member

Planning and designof turnkey PowerTransmission Systems(PTS)

General contractor

PowerTransmissionSystems

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High-Voltage Power Transmission Systems

Fig. 3: AC or DC transmission costs over distance

System optimization and engineering

One major task for the system engineeringexperts is the comparison and the assess-ment of various concepts. The basic param-eters are transmission capacity and volt-age, along with the transmission distance.Having the turnkey responsibility, Siemenscan optimize the transmission systemtechnically and economically in order tofind the transmission system whichis tailored to our customer‘s demands.

Depending on boundaryconditions

Breake-even-point HVAC

HVDC

Costs

Distance

Cost comparison between 3-phase HV AC trans-mission and HV DC transmission

Training

Customer training is a very important taskin project management and our servicedepartment specializes in customer train-ing. In the sessions and courses Siemensdistinguishes between operation and main-tenance staff training. The station opera-tors are mainly trained in handling of thecontrol and protection systems and theirfunctions, whereas the maintenanceteams are specially introduced to the maincomponents.The training activities comprise classroomsessions, giving the theoretical back-ground, as well as practical instruction onsite in order to familiarize the customerswith the individual items of equipment.

Tailored financial solutions

As a globally structured company, Siemensis prepared to participate in the financingof a power transmission project. Depend-ing on the requirements, there are differ-ent possibilities covering supplier’s creditas well as complete project financing likeBuild Operate and Transfer (BOT) or nu-merous alternative models.

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High-Voltage Power Transmission Systems

Fig. 4

Service

Our service activities cover all necessarychecks, inspection and other maintenanceactivities. With the use of special diagnos-tic systems, also remote controlled, thecauses for outages or malfunctions of indi-vidual equipment can be found easily.

For further information please contact:

Fax: ++ 49 - 9131- 73 4672

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Siemens Power Engineering Guide · Transmission & Distribution

Conversion Factors and Tables

320°

305°

290°

275°

260°

245°

160°

150°

140°

130°

120°

110°

100°

90°

230°

212°

200°

185°

170°

155°

80°

70°

60°140°

50°

40°

30°

20°

10°

125°

110°

95°

80°

65°

50°

32°

20°

–10°

–25°

–10°

–20°

–30°

–40°–40°

°C°F

0.6530.8321.040

1.310

1.650

2.080

2.620

19 AWG18

1716

1514

13

0.75

1.50

2.50

12

1110

98

7

4.00

6.00

10.00

16.00

3.310

4.1705.260

6.6308.370

10.550

13.30016.770

21.150

26.67033.630

6

5

4

32

1

25.00

35.00

50.00

70.00

42.410

53.48067.430

95.00

120.00

150.00

85.030

107.200126.640152.000

202.710

1/0

2/0

3/0

4/0250 MCM300

400500600700800

1000

253.350304.000354.710405.350506.710

185.00

240.00

300.00

400.00

500.00625.00

Cross-sectionalconductorarea

[mm2]

EquivalentMetric CSA

[mm2]

AWG or MCM

Metric cross-sectional areasacc. to IEC

American wire gauge

Non-metric system SI system

Length

1 mil

1 in

1 ft

1 yd

1 mile

0.0254 mm

2.54 cm = 25.4 mm

30.48 cm = 0.305 m

0.914 m

1.609 km = 1609 m

Non-metric systemSI system

1 mm

1 cm

1 m

1 km

39.37 mil

0.394 in

3.281 ft = 39.370 in = 1.094 yd

0.621 mile = 1.094 yd

Area

1 in2

1 ft2

1 yd2

1 acre

1 mile2

6.452 cm2 = 654.16 mm2

0.093 m2 = 929 cm2

0.836 m2

4046.9 m2

2.59 km2

1 mm2

1cm2

1 m2

1 km2

0.00155 in2

0.155 in2

10.76 ft2 = 1550 in2

= 1.196 yd2

0.366 mile2

Non-metric system SI system

Non-metric systemSI system

Cross-sectional conductor areasto Metric and US Standards

Temperature

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Siemens Power Engineering Guide · Transmission & Distribution

Conversion Factors and Tables

Volume rate of flow

1 gallon/s

1 gallon/min

1 ft3/s

1 ft3/min

3.785 l/s

0.227 m3/h = 227 l/h

101.941 m3/h

1.699 m3/h

Non-metric system SI system

Non-metric systemSI system

1 l/s

1 l/h

1 m3/h

0.264 gallon/s

0.0044 gallon/min

4.405 gallon/min =0.589 ft3/min = 0.0098 ft3/s

Mass, weight

1 oz

1 lb

1 sh ton

28.35 g

0.454 kg = 453.6 g

0.907 t = 907.2 kg

1 g

1 kg

1 t

0.035 oz

2.205 lb = 35.27 oz

1.102 sh ton = 2205 lb

Non-metric system SI system

Non-metric systemSI system

Velocity

1 ft/s

1 mile/h

0.305 m/s = 1.097 km/h

0.447 m/s = 1.609 km/h

1 m/s

1 km/h

3.281 ft/s = 2.237 mile/h

0.911 ft/s = 0.621 mile/h

Non-metric system SI system

Non-metric systemSI system

Volume

1 in3

1 ft3

1 yd3

1 fl. oz.

1 quart

1 pint

1 gallon

1 barrel

16.387 cm3

28.317 dm3 = 0.028 m3

0.765 m3

29.574 cm3

0.946 dm3 = 0.946 l

0.473 dm3 = 0.473 l

3.785 dm3 = 3.785 l

158,987 dm3 = 1.589 m3

= 159 l

1 cm3

1 dm3

= 1 l

1 m3

0.061 in3 = 0.034 fl. oz.

61.024 in3 =0.035 ft3 = 1.057 quart =2.114 pint = 0.264 gallon

0.629 barrel

Non-metric system SI system

Non-metric systemSI system

Force

1 lbf

1 kgf

1 tonf

4.448 N

9.807 N

9.964 kN

0.225 lbf = 0.102 kgf

0.100 tonf

Non-metric system SI system

Non-metric systemSI system

1 N

1 kN

Torque, moment of force

1 lbf in

1 lbf ft

0.113 Nm = 0.012 kgf m

1.356 Nm = 0.138 kgf m

8.851 lbf in = 0.738 lbf ft(= 0.102 kgf m)

Non-metric system SI system

Non-metric systemSI system

1 Nm

Moment of inertia J.

Numerical value equation: J = = Wr 2GD2

4

1 lbf ft2 0.04214 kg m2

23.73 lb ft2

Non-metric system SI system

Non-metric systemSI system

1 kg m2

Pressure

1 in HG

1 psi

1 lbf/ft2

1 lbf/in2

1 tonf/ft2

1 tonf/in2

0.034 bar

0.069 bar

4.788 x 10-4 bar =4.882 x 10-4 kgf/cm2

0.069 bar = 0.070 kgf/cm2

1.072 bar = 1.093 kgf/cm2

154.443 bar =157.488 kgf/cm2

1 bar= 105 pa= 102 kpa

29.53 in Hg =14.504 psi =2088.54 lbf/ft2 =14.504 lbf/in2 =0.932 tonf/ft2 =6.457 x 10-3 tonf/in2

(= 1.02 kgf/cm2)

Non-metric system SI system

Non-metric systemSI system

Energy, work, heat

1 hp h

1 ft lbf

1 Btu

0.746 kWh = 2.684 x 106 J= 2.737 x 105 kgf m

0.138 kgf m

1.055 kJ = 1055.06 J(= 0.252 kcal)

1 kWh

1 J

1 kgf m

1.341 hp h = 2.655 kgf m= 3.6 x 105 J

3.725 x 10-7 hp h =0.738 ft lbf =9.478 x 10-4 Btu(= 2.388 x 10-4 kcal)

3.653 x 10-6 hp h =7.233 ft lbf

Non-metric system SI system

Non-metric systemSI system

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Conversion Factors and Tables

1 km = 1000 m;1 m = 100 cm = 1000 mm

1 km2 = 1000 000 m2;1 m2 = 10 000 cm2;1 cm2 = 100 mm2

1 m3 = 1000 000 cm3;1 cm3 = 1000 mm3

1 t = 1000 kg; 1 kg = 1000 g

1 kW = 1000 W

Specific steam consumption

1 lb/hp h 0.608 kg/kWh

1 kg/kWh 1.644 lb/hp h

Non-metric system SI system

Non-metric systemSI system

Power

1 hp

1 ft lbf/s

1 kcal/h

1 Btu/h

0.746 kW = 745.70 W =76.040 kgf m/s(= 1.014 PS)

1.356 W (= 0.138 kgf in/s)

1.163 W

0.293 W

1 kW

1 W

1.341 hp =101.972 kgf m/s(= 1.36 PS)

0.738 ft lbf/s = 0.86 kcal/h= 3.412 Btu(= 0.102 kgf m/s)

Non-metric system SI system

Non-metric systemSI system

Temperature

°F °C°F K

(ϑF – 32) = ϑC

ϑF + 255.37 = T

Non-metric system SI system

Non-metric systemSI system

5659

°C °FK °F

ϑC + 32 = ϑF

ϑ T – 459.67 = ϑF

9595

Note:Quantity Symbol Unit

Fahrenheittemperature

Celsius (Centigrade)temperature

Thermodynamictemperature

* The letter t may be used instead of ϑ

ϑF*

ϑC*

T

°F

°C

K(Kelvin)

Examples for decimal multiplesand submultiples of metric units

Conditions of Sale and Delivery

Subject to the “General Conditions of Sup-ply and Delivery for Products and Servicesof the Electrical and Electronics Industry”.The technical data, dimensions andweights are subject to change unlessotherwise stated on the individual pagesof this catalog.The illustrations are for reference only.