8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
1/16
The easy way to build
switchgear and controlgear
assemblies in compliance with the regulations
A guide for partially type-tested switchgear andcontrolgear assemblies in compliance with EN 60 439
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
2/16
What are the requirements?
My name is Rocky, and Im
looking forward to showing
you the way through these
guidelines.
Contents Page
EN 60 439 is recognised as the
established engineering practice for
switchgear and controlgear assemblies 3
What are the bases of
the agencies requirements? 4
Which control systems and
installations are subject to EN 60 439? 5
What is considered as a low-voltage
switchgear and controlgear assembly -
(ASSEMBLY) under EN 60 439? 6
What is the difference between
a TTA and a PTTA? 6
What does EN 60 439 define? 8
Directives for the utilisation of other
components as those applied for the
type-test of a TTA permit a range of freedom 10
Type-tested components simplify work 10
The added value performed by the ASSEMBLY
maufacturer requires safety verification 11
Calculation software simplifies verification
of the temperature rise 12
Special care with short-circuit
currents above 10 kA 12
Which tests must be performed on PTTA? 13
How can the expense for the technical
verification of PTTA be minimised? 13
Important notes regarding national
differences 13
Compilation of verifications and tests
of TTA and PTTA 14
A Manufacturers
Declaration, a Type-testing
Report and Routine Test
Protocol are required as asafety verification.
2
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
3/16
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
4/16
4
What are the bases of the agencies
requirements?
The requirements are based upon the Low-voltage
Directive 73/23/EEC and the EMC Directive
89/336/EEC of the EU, as well as on their supple-
mentation by Directive 93/68/EEC, which concerns
the CE-marking.
In its fundamental requirements, the Low-voltage
Directive postulates the protection of persons, ani-
mals and property from the hazards and damage
which may result from electrical apparatus.
The EMC Directive states in Article 4:
The apparatus referred to in Article 2 shall be
so constructed that:
a) the electromagnetic disturbance it generates
does not exceed a level allowing radio and
telecommunication equipment and other
apparatus to operate as intended;
b) the apparatus has an adequate level of
intrinsic immunity of electromagnetic distur-
bance to enable it to operate as intended.
......
The central focus is on the pro-
tection of persons, animals andproperty as well as operation in
the intended manner without
malfunctions.
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
5/16
Which control systems and
installations are subject to EN 60 439?
The standard cites (Subparagraph 1.1)
- stationary or movable assemblies,
- with or without enclosure,
- for use in connection with generation, transmis-
sion, distribution and conversion of electric
energy and for the control of electrical energy
consuming equipment.
EN 60 439 does not apply to individual devices for
which valid standards exist (motor starters in com-
pliance with IEC 947, for instance).
It follows from this that all electrical controls, distri-
bution boards and switchgear and controlgear
assemblies fall under EN 60 439.
It may not be concluded that EN 60 439 is the sole
standard to be applied. In the case of machine con-
trols, for instance, additional requirements in com-
pliance with EN 60 204 (Electrical Equipment ofMachines) must be fulfilled.
The EU Directives for low-voltage devices
(73/23/EEC) and for Electromagnetic Compatibility
(89/336/EEC) are valid in all countries of the
European Union (EU) and of the European Economic
Area (EEA) and in Switzerland (Ordinance on elec-
trical low-voltage equipment and Ordinance on
electromagnetic compatibility). Similar rules
which are based to a great extent on the directives
of the EU are valid or will soon be introduced in
other countries, such as the Commonwealth of
Independent States (CIS) or Australia.
5
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
6/16
6
What is the difference between a TTA
and a PTTA?
Type-tested low-voltage switchgear and
controlgear assembly (TTA)
EN 60 439-1 Subparagraph 2.1.1.1:
A low-voltage switchgear and controlgear
assembly conforming to an established type or
system without deviations likely to significantly
influence the performance, from the typical
ASSEMBLY verified to be in accordance with
this standard.
A TTA is thus an ASSEMBLY which has been test-
ed as a type (manner of construction) in compliance
with EN 60 439. Examples are LV distribution
boards and Motor Control Centers (MCC). A worst-
case configuration is tested (e.g. regarding tempera-
ture rise). TTA are designed for series production,
whereby the individual TTA corresponds to the
established type, but adapted to the specific applica-
tion (e.g. number and performance of the outgoing
circuits). TTA typically possess structural parts spe-
cific to the manufacturer such as plug-in modules,
busbar systems, locking devices, etc., which are not
available as universally-applicable components.
TTA are typically applied with installations
designed for control and distribution and with
installations with high short-circuit current level.
Partially type-tested low-voltage switchgear
and controlgear assembly (PTTA)EN 60 439-1 Subparagraph 2.1.1.2:
A low-voltage switchgear and controlgear
assembly, containing both type-tested and
non-type-tested arrangements provided that
the latter are derived (e.g. by calculation)
from type-tested arrangements which have
complied with the relevant tests ().
What is considered as a low-voltage
switchgear and controlgear assembly
(ASSEMBLY) under EN 60 439?
In accordance with EN 60 439-1, Subparagraph2.1.1., a low-voltage switchgear and controlgear
assembly is
A combination of one or more low-voltage
switching devices together with associated con-
trol, measuring, signalling, protective, regulating
equipment, etc., completely assembled under the
responsibility of the manufacturer with all the
internal electrical and mechanical interconnec-
tions and structural parts ().
Note 3 states:
For various reasons, for example transport or
production, certain steps of assembly may be
made in a place outside the factory of the manu-
facturer.
Thus, an ASSEMBLY is spoken of whenever low-volt-
age switching devices and protective and regulating
equipment are involved. EN 60 439 applies for
ASSEMBLIES up to 1,000 volts a.c. and 1,500
volts d.c.
TTA are tested as a type and
are frequently optimised forspecific applications.
PTTA consist of type-tested
components, or such which arederived from them.
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
7/16
PTTA are thus controls and installations which are
not tested in their entirety as a type. They are com-
piled from components which are either type-tested(e.g. contactors, circuit breakers, load break switch-
es, fuses etc.), or which are derived from type-tested
arrangements (e.g. busbar system). The temperature
rise, for example, can be derived (i.e. not mea-
sured), either
- in accordance with HD 528 S2 (IEC 890;
A method of temperature-rise assessment by
extrapolation for partially type-tested assem-
blies (PTTA) of low-voltage switchgear and
controlgear) or
- with the aid of temperature-rise calculation
software programs from enclosure manufac-
turers (which are based in turn on type-tests)
or
- based on similarity with previously manufac-
tured (and measured) ASSEMBLIES.
The essential difference between TTA and PTTA
exists in the fact that TTA are optimised for specific
(repetitious) applications and that, thanks to the
measurement, it is possible to utilize the compo-
nents to the limit of their load capacity. TTA are
procured as complete installations from one manu-
facturer or built under his licence.
In contrast to this, the PTTA construction method is
typically selected by builders of switchgear and
controlgear assemblies who opt forcomponents
from different manufacturers instead of the costly
type-test and the commitment to one manufacturer.
They derive the correct selection of the components
for their specific application from the type-tests of
the manufacturers and install them in accordance
with the established engineering practice. This
applies for single assemblies and also for series pro-
duction. PTTA generally possess more reserve (e.g.
with regard to temperature rise and the selection of
the conductor cross sections), since the derivation is
based on general rules (e.g. regarding the selection
of conductors).
TTA and PTTA are equal in regard to the fulfilment of
safety requirements.7
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
8/16
8
What does EN 60 439 define?
EN 60 439 definesthe design and construction requirements which must
be fulfilled in order to achieve the safety objectives,
the definitions which are significant for ASSEMBLIES,
the referential environmental conditions,
the test requirements, etc.
EN 60 439 thus represents an extremely useful set of
instructions for the set-up and testing of ASSEMBLIES and
forms a basis for communication between manufacturer,
customer and agencies. The manufacturers and operators of
ASSEMBLIES should become familiar with EN 60 439 in
order to meet their responsibility for the safety of the equip-ment.
EN 60 439 (Low-voltage switchgear and controlgear
assemblies) is organised into the parts listed below:
EN 60 439-1 Part 1: Type-tested and partially type-tested assemblies.
EN 60 439-2 Part 2: Particular requirements for busbar trunking systems
(busways)
EN 60 439-3 Part 3: Particular requirements for low-voltage switchgear and
controlgear assemblies intended to be installed in places
where unskilled persons have access for their use
Distribution boards
EN 60 439-4 Part 4: Particular requirements for assemblies for construction
sites (ACS)
EN 60 439-5 Part 5: Particular requirements for assemblies intended to be
installed outdoors in public places Cable distribution
cabinets (CDCs) for power distribution in networks
There are supplements for some of these Parts which are integrated into the
respective basic Part upon revisions of the standards.
The following documents supplement EN 60 439 for specific areas of technology:
HD 528 S2 A method of temperature-rise assessment by extrapolation for(IEC 890) partially type-tested assemblies (PTTA) of low-voltage
switchgear and controlgear.
IEC 1117 A method for assessing the short-circuit withstand strength of
partially type-tested assemblies (PTTA)
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
9/16
9
The contents of EN 60 439-1, the fundamental part of the regulatory ordi-
nance, are compiled below:
1. General
2. Definitions
3. Classification of ASSEMBLIES
4. Electrical characteristics of ASSEMBLIES
5. Information to be given regarding the ASSEMBLY
5.1 Nameplates
5.2 Markings
5.3 Instructions for installation, operation and maintenance
6. Service conditions
7. Design and construction
7.1 Mechanical design
7.2 Enclosure and degree of protection
7.3 Temperature rise
7.4 Protection against electric shock
7.5 Short-circuit protection and short-circuit withstand strength
7.6 Switching devices and components installed in ASSEMBLIES
7.7 Internal separation of ASSEMBLIES by barriers or partitions
7.8 Electrical connections inside an ASSEMBLY: bars and insulated
conductors
7.9 Requirements for electronic equipment supply circuits
7.10 Electromagnetic compatibility
8. Test specifications8.1 Classification of tests
8.2 Type-tests
8.3 Routine tests
Annexes
A (normative) Minimum and maximum cross-sections of copper con-
ductors suitable for connection
B (normative) Method of calculating the cross-sectional area of pro-
tective conductors with regard to thermal stresses due to currents of
short duration
C (informative) Typical examples of ASSEMBLIESD (informative) Typical arrangements of forms of separation by barri-
ers or partitions
E (informative) Items subject to agreement between manufacturer
and user
F (normative) Measurement of creepage distances and clearances
G (normative) Correlation between the nominal voltage of the supply
system and the rated impulse withstand voltage of the equipment
H (informative) Bibliography
ZA (normative) Other international publications cited in this standard
with references to the relevant European publications
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
10/16
10
What must be observed in theand testing of a PTTA?
Type-tested components simplify work
PTTA represent the majority of control systems or
distribution boards in unit production. Observing
established engineering practice, careful selection of
products, and competent construction, the assembly
of a control system which conforms to directives
poses no problem and corresponds to the established
practice of reliable switchboard manufacturers.
The documentation of the component manufacturers
are an essential support tool for project planners as
well as the builders of ASSEMBLIES. In accordance
with the Low-Voltage and the EMC Directive, all
components must fulfil the relevant directives and be
type-tested. The type-tests of the components are
performed in compliance with the respective stan-
dards for the components (e.g. in compliance withEN 60 947 for low-voltage switching devices) and
not in compliance with EN 60 439 (refer to EN
60 439-1 Subparagraph 1.1: This standard does not
apply to individual devices and self-contained com-
ponents, such as motor starters, fuse switches, elec-
tronic equipment, etc., complying with their relevant
standards).
The component manufacturers issue relevant
Declarations of Conformity and identify theproducts for the EU with the CE-mark. The user of
such type-tested components can assume that the
relevant standards are fulfilled, provided that these
components are installed in accordance with the
manufacturers specifications (those which form the
basis of the type-test). This applies for the areas of
the Low-voltage Directive as well as the EMC
Directives for the utilisation of other
components as those applied for the
type-test of a TTA permit a range of
freedom
EN 60 439 states in Subparagraph 8.1.1:
If modifications are made to the components
of the ASSEMBLY, new type tests have to be
carried out only in so far as such modifica-
tions are likely to adversely affect the results
of these tests.
This rule provides the manufacturer of a specific
TTA a relatively wide range of freedom regarding
the selection of the switchgear and other compo-
nents. It is entirely feasible that devices other than
those employed in the type-test may be installed
without affecting the validity of the type-test, for
example when:
- the maximum temperature rise is not exceeded
(e.g. through selection of devices of the same
or lower power dissipation),
- the insulation withstand strength is not low-
ered (e.g. through selection of devices of the
same or better insulation),
- the short-circuit withstand strength is main-
tained (e.g. through selection of circuit break-
ers with the same or higher breaking capacity
and the same or more favourable let-through
values).
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
11/16
11
construction, modification
Directive. Among other things which deserve special
attention are the manufacturers specifications
regarding load capacity with increased ambient tem-
perature, the performance data for short-circuit
stress, the safety distances from arcing apertures,
etc.
The job of the ASSEMBLY manufacturer is simpli-
fied if he can refer to type-tests or technical docu-
mentation from the component manufacturer forcomponent subassemblies, as is the case with the
MCS-Star provided by Rockwell Automation for
motor starters of the Modular Control System
(MCS). He is thus freed from the burden of select-
ing and dimensioning the components installed in
the subassembly.
The added value performed by the
ASSEMBLY maufacturer requires
safety verification
While it is possible to rely upon the type-tests con-
ducted for devices by the component manufacturer,
the ASSEMBLY manufacturer bears the responsibil-
ity for work he has performed, such as selectingcorrectly-dimensioned conductors and their protec-
tion. Here, he can rely upon the relevant guidelines
such as those set down in Harmonization Document
HD 384.5.523, with consideration for the type of
conductor, the temperature limit of the conductor
insulation, the ambient temperature, the conductor
loading and the method of installation.
Helpful software tools such as
MCS-Star produced by Rockwell
Automation simplify the work of
ASSEMBLY manufacturers.
Which starter?
Starter selection
Circuit diagram
Layout
Assembly test
Starter selection
Catalog Nr.
Bills of Materials Circuit diagram Project Terminate
Function
Star-Delta starter
Mechanical locking
Without mechanical locking
Control type
Short-circuit coordination
Coordination Type "1"
Control voltage
220-230V 50Hz
230V 50 / 60Hz
230-240V 50Hz
240V 50Hz / 277V 60Hz
Motor protection
Electrical motor protection relay,terminal 10 man.
Current limiter
Star-Delta time relay
Electronic timer module, 30 seconds
Assembly system
Motor output at 400 /415 V 50 Hz
7.50 kW / 14.8 A
9.00 kW / 19.0 A
11.0 kW / 21.5 A
15.0 kW / 29.0 A
170-C16NKF10-A1G-TY-E-X
Layout
Circuit diagram 170-005 Layout S00SEATX
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
12/16
12
Calculation software simplifies
verification of the temperature rise
Harmonization Document HD 528 S2 (IEC 890)
applies as the established engineering practice for
the determination of the temperature rise in the
switchgear cabinet with natural cooling.
Suppliers of enclosures and cabinets provide soft-
ware for temperature-rise calculation based on
proven calculation methods and which allow verifi-
cation of temperature rise and any cooling measures
required without undue outlays for the user.
The project planner takes the power dissipation of
the components from the catalogues or databases of
the product manufacturers, while the software
ensures the correct sizing.
In the event that similar control units (e.g. same
cabinet size with comparable power dissipation of
the components in a similar construction) are built
successively, the verification for temperature rise
can also be derived from the observance of similari-
ty with the first system whose temperature rise was
either measured or calculated.
Special care with short-circuit
currents above 10 kA
EN 60 439 exempts testing of short-circuit with-
stand strength at rated short-circuit currents below
10 kA. Nor is verification of the short-circuit with-
stand strength required for protection with current-
limiting devices such as current-limiting fuses or
circuit breakers when the let-through current does
not exceed 15 kA at rated breaking capacity.
As a result, significant costs for testing are eliminat-
ed for many control systems and installations.
Short-circuit currents of 10 kA presuppose the
direct connection to a transformer with an output of
approx. 400 kVA (at 400 V secondary voltage and
6% short-circuit voltage) and are rare with smaller
loads. Because of the hazards of short circuits,
extreme caution regarding the short-circuit with-
stand strength should be taken and it must be
ensured that either the limits of 10 kA and 15 kA
respectively are not exceeded, or that the installation
possesses the necessary robustness at higher levels
of short circuit current.
It is advisable to rely upon type-tested components
and arrangements, even for PTTA where busbars are
involved. The selection and application of the bus-
bar in compliance with manufacturers specifica-
tions (based on his type-test) ensures a design that
conforms to requirements.
In addition, Technical Report IEC 1117 provides
instructions for the design of PTTA which is resis-
tant to short-circuits, especially regarding connec-
tion of the equipment.
Current limiting circuit breakers can
eliminate the necessity for verifica-
tion of short-circuit withstand
strength.
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
13/16
Which tests must be performed on PTTA?
Table 7 of EN 60 439-1 lists the tests which are tobe performed on PTTA (and TTA). In the selection
of type-tested components, or those derived from
them, and for the execution of calculations in com-
pliance with recognised methods, verification may
be achieved without difficulties.
It is recommended that standardised protocols are
prepared for the documentation of the tests or
whenever available that protocol forms made
available by professional societies are used.
How can the expense for the technical
verification of PTTA be minimised?
Together with the selection of type-tested compo-
nents for which no further verification is required
since reference may be made to the type-test of the
respective manufacturer, it is recommended to stan-
dardise the internal bespoke documentation and pro-
cedures for the services of the planning engineerand builder of ASSEMBLIES and to incorporate
these standards into a quality assurance system.
Given careful work in compliance with these inter-
nal standards, technical verification for all installa-
tions assembled in compliance with them is guaran-
teed. With sizing for which either standards or
industry-specific table references are available, for
example, it is recommended that these be incorpo-
rated. It may be anticipated that industrial societies
will support their members increasingly in the fulfil-ment of this task.
Important notes regarding national
differences
The standards and Harmonization Documents
referred to in this brochure are cited with the num-
bers and designations in accordance with CEN-
ELEC or IEC. The numbers and designations may
deviate in some countries because of national sys-
tems. However, the national standards are identi-
cal in their contents and cite the documents
which form the basis at the European level in all
cases.
Software for calculation of temper-
ature rise and short-circuit current
are helpful support tools.
Careful routine testing
ensures the safety of the
individual ASSEMBLY.
13
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
14/16
14
Compilation of verifications and tests of TTA and
recommendations for the practical execution with
Seq Requirements Section TTA
no. to be tested
1 Limiting excess 8.2.1 Verification of compliance
temperature of limiting excesstemperature by testing (type-test)
2 Insulation withstand 8.2.2 Verification of the insulation
strength withstand strength by testing
(type-test)
3 Short-circuit 8.2.3 Verification of short-circuit withstand
withstand strength strength by testing (type-test)
4 Efficiency of the 8.2.4 Verification of the proper connection
protective conductor between conductive parts of the
switchgear and controlgear
Proper connection between 8.2.4.1 assembly and protective conductors
conductive parts of the by inspection or resistance measurement
switchgear and controlgear (type-test)
assembly and protective
conductors
Short-circuit withstand 8.2.4.2 Verification of the short-circuit withstand
strength of the protective strength of the protective conductor
conductor by testing(type-test)
5 Creepage distances and 8.2.5 Verification of the creepage
clearances distances and clearances
(type-test)
6 Mechanical 8.2.6 Verification of the mechanical
function function (type-test)
7 Type of protection 8.2.7 Verification of the type of protection
(type-test)
8 Wiring, 8.3.1 Visual inspection of the switchgear and
electrical function controlgear assembly, including the wiring
and electrical function test where required
(routine test)
9 Insulation 8.3.2 Insulation test
(routine test)
10 Protective measures 8.3.3 Inspection of protective measures and visual
inspection of the continuous protective
conductor connection (routine test)
11 Leakage resistance 8.3.4 -
Subparagraphs 8 to 11 are routine tests
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
15/16
15
PTTA (Table 7 from EN 60 439-1) supplemented with
PTTA.
PTTA Comments for PTTA
Verification of compliance Determination in accordance with HD 528 S2 or
of limiting excess temperature with the use of temperature-rise calculationby testing or extrapolation of TTA software from enclosure manufacturers
Verification of the insulation withstand The verification of the insulation resistance
strength in compliance with Section 8.2.2 (measurement at 500 V) will be the
or verification by insulation test in com- easiest to conduct in most instances.
pliance with Section 8.3.2 or verification
of the leakage resistance in compliance
with Section 8.3.4 (refer to Seq. no. 11)
Verification of short-circuit withstand Not required up to 10 kA (or 15 kA let-through current respectively).
strength by testing or extrapolation of Beyond this, use of type-tested busbar systems recommended.
similar type-tested arrangements Extrapolation in accordance with manufacturer's documents and
execution in accordance with IEC 1117.Verification of the proper connection
between conductive parts of the
switchgear and controlgear
assembly and protective conductors
by inspection or resistance measurement
Verification of the short-circuit withstand For PTTA, separate protective conductors must be provided (protective
strength of the protective conductor by connections via constructional parts are not allowed) in such a manner
testing or corresponding execution and that the influence of the electromagnetic forces of the busbars may bearrangement of the protective conductor ignored (i.e., at a distance from the busbars).
(refer to Section 7.4.3.1.1, last paragraph)
Verification of the creepage Use of type-tested components and special attention to the clearances
distances and clearances from enclosures and other conducting parts.
Observance of arcing spaces.
Verification of the mechanical Especially for plug-in modules and locking devices. Occurs rarely with
function PTTA or is covered by the use of type-tested components.
Verification of the type of protection Use of suitable type-tested enclosures and installation components.
Installation of components in the switchgear cabinet surface in
compliance with instructions of the component manufacturer
for the relevant type of protection.
Visual inspection of the switchgear and
controlgear assembly, including the
wiring and electrical function test
where required
Insulation test or verification of the See note regarding Subparagraph 2
leakage resistance in compliance with
Section 8.3.4 (refer to Seq. no. 11)
Inspection of protective measures Visual inspection of the protective conductor connections and random
sample tests of the threaded connections.
Verification of the leakage resistance, See note regarding Subparagraph 2
if the test was not conducted in com-
pliance with Section 8.2.2 or 8.3.2
(refer to Seq. no. 2 and 9)
8/10/2019 Allen Bradley Guide Switchgear-controlgear Assembly
16/16
More Than 500000 Ways To Make Automation Work
Power devices Circuit breakers
Motor contactors and starters
Motor protection
Motor Control centers
Power monitoring
Sensors Limit, photoelectric and proximity switches
Pressure and temperature controls
Radio frequency identification
Bar code
Encoders
Vision systems
Operator interface Push buttons and pilot devices
Cam switches
Message displays
Operator panels, terminals
Motion Control AC and DC drives
Drive systemsComputer numerical controls
General purpose motion control
Logic devices Programmable controlers
Universal I/O
Control and information processing
Relays
Terminal blocks
Communication Automation control networks
products Multivendor connectivity (MAP)
Application systems Custom engineered control systems
Batch control
Burner management systems
Distributed discrete manufacturing control
SCADA
Stamping press control systems
Quality management SPG/SQC data collection and analysis
Global support Technical training
services Field engineering and service
Repair and exchange services
Technical support
Top Related