Electrical Distribution

Wednesday, February 11, 2009

Electrical Power Distribution in Buildings

စကမႈထြနးကားလာတာ န႔ အတ လပစစဓာတအား သးစြ မႈ ကလညး ပမလာပါတယ။ မးထြနးဘ႔၊ အမသးဘ႔ သာမက စကရအလပရ န႔အေဆာကအအ ေတြ၊ လမးပနးဆကသြယေရး ေတြ မာပါ မရမျဖစ အေရးပါ လာပါတယ။အရင တငျပေပးထားခဘးတ MEP Systems ေတြ အေၾကာငးထမာ လညး Electrical Systems အမးမး ေတြ အေၾကာငးကစာဖတသ န႔ မတဆက ေပးထားခပါတယ။ဒတစပါတေတာ Building Electrical Service ထ က Electrical Power Distribution အေၾကာငးက စာဖတသ န႔မတဆကေပးဘ႔ ရညရြယ ထားပါတယ။

စာေရးသ က Mechanical အဓက မ႔ Lighting & Power က ဒဇငး အေျခခ ေလာက န႔ Design Coordination လပတ အခါသထားသင တာေတြ က ပ Applied Electrical Power အေန န႔ တငျပေပးႏင ပါတယ။ ပမ အေသးစတ သခငရငေတာစာလညးဖတ၊ ေလလညးေလလာ၊ အေတြ႕အႀက ရတ Electrical Engineer ဆမာ လညး ဆညးပးပါ လ႔ တကတြနး လကပါတယ။မျငမးစရာ စာအပေတြ ကလညး ေအာကက References Section မာ ထညသြငး ေပးထားပါတယ။အဓက တငျပေပးမာ ကေတာ အေဆာကအအ အတြငး သး Low Voltage (LV) Systems ေတြ အေၾကာငး ျဖစပါတယ။

1. Introduction to Electrical Power Distribution in Buildings2. Power Distribution Systems3. AC Fundamentals4. Power Grids, Preliminary Load Estimates, Basic Metering Scheme5. Major Components

i. High Tension (Medium Voltage) Switchgearii. Transformersiii. Standby Power Generatorsiv. Main Switch Boardv. Control Systemsvi. Fuse, Circuit Breakers, Protective Devices

vii. Earth fault protection6. Cable Sizing / Voltage Drop7. Basic Design8. Regulations

I. Introduction to Electrical Power Distribution in Buildingsအတနသင ႀကးမားတ အေဆာကအအ တစခ အတြက Power Distribution Systems ေတြ႕ရေလ ရတ arrangement ကေအာကမာ ေဖာျပထားပါတယ။

i. Power Grids SubstationUtility Company အတြက Sub-station ပါ။ HT Switch Gear ျဖစၿပး အဓက ပါဝငမာ က Hightension အတြက သငေတာတ Circuit Breaker န႔ Control Components ေတြ ျဖစၾကပါတယ။Equipment ေတြ က Utility Company က တပဆင ေပးပါလမ မယ။Switchgear : An assembly of main and auxiliary switching apparatus for operating,regulating, protection or other control of an electrical installation.

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Singapore: M&E and AutoCADRevit MEP 2010

MEP SystemsM&E Systems vs BuildingsM&E Systems ဆတာ ဘာေတြလ။Scope of M&E SystemsM&E: ေနရာ လာထားသတမတျခငးM&E န႔ Architectural ဒဇငးM&E န႔ ကနကစရတM&E Design: High-Rise BuildingsTesting & Commissioning Process

HVACHVAC: Introduction to DesignHVAC: Building in Hot & Humid ClimateM&E Basics: Pipe & Duct SizingHVAC: Duct Sizing with VBAHVAC: Duct Sizing

Automatic Control SystemsHVAC Control (01) : FCU

PlumbingSanitary Plumbing: Introduction

Domestic Water Supply: Introduction

Water Tanks ( ေရကန မား )

Swimming PoolsSwimming Pools (ေရကးကန မား)

Fire ProtectionFire Protection : IntroductionSmoke Control: Pressurization SystemsFire Sprinkler (Wet) System, S'poreျမနမာျပည ၿမေတာ ေစးမား န႔ မး ေဘးကာကြယေရး။

ElectricalElectrical Power Distribution

Sustainable, Green and EnvironmentGreen Buildings: USGBC's LEED/

S'pore GreenMarkUnderstanding LEEDGreen EnergyClean Air: ေလေကာငးေလသန႕Clean Water: ေရေကာငးေရသန႔

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ii. Consumer Substationအေဆာကအအ ပငရင ရ Substation မ႔ Consumer Sub-station လ႔ေခၚတာ ပါ။ HT Switch Gearျဖစၿပး အဓက ပါဝငမာ က High tension အတြက သငေတာတ Circuit Breaker န႔ ControlComponents ေတြ ျဖစၾကပါတယ။ Gas Insulated န႔ Air Insulated Switchgear ေတြ က အသးမားၿပးအထမာ ပါဝငတ Circuit Breaker ကေတာ SF6 Insulated Circuit Breaker (or) Vacuum CircuitBreaker ျဖစႏငပါတယ။A circuit breaker is a safety device enabling switching and protection of electricaldistribution networks.

iii. Transformersဒမာ သးတ Transformer ရ တာဝနက medium voltage ကေန အမသး၊ စကရသး Equipment န႔Electrical Appliance ေတြ အတြက သငေတာတ voltage ရေအာင step down လပေပးဘ႔ပါ။Transformers : A device that is used to convert electricity energy from higher a.cvoltage to desire consumer voltage (step down) or vice versa.

iv. Standby Emergency Power Generatorsအေရးေပၚ အေျခအေန မာ လအပမ Life Safety Systems ေတြ န႔ မးျပတရင ဆးရႈးမႈ အမားႀကးရႏငတစကပစၥညး ေတြ အတြက လအပမ standby power ေပးဘ႔ အတြက တြကခက တပဆငထားတ(အမားအားျဖင) ဒဇယ Standby Power Generator ကေခၚတာပါ။Standby Emergency Power Generators : Electricity Generator set driven by prime moverand of sufficient capacity to supply circuits carrying emergency loads with suitablemeans for automatic starting of the prime mover on failure of normal service

v. Main Switchboard (MSB)Switchboard : An assembly of switchgear with or without instruments, but the termdoes not apply to groups of local switches in final circuits.

vi. Emergency Main Switchboard (EMSB)Utility Network ကဝငလာတ မးျပတေတာက ခ ရင Standby Back-up Electricity ကေနအလအေလာက လပစစပါဝါ ေျပာငးေပးႏငဘ႔ တပဆငထားတ Switchboard ပါ။ အေရးအႀကး ဆး ကေတာလေတြ ရ အသက life safety က ေစာငေရာကဘ႔ တပဆငထားတ Fire Protection, Smoke controlsystems, Emergency Lighting န႔ Emergency evacuation support systems ေတြအတြကမရမျဖစ လအပပါတယ။Emergency Power : To supply electrical power automatically in the event of failure ofthe normal supply to protect equipment essential of safety to life

vii. Building Power DistributionTransformer အဝငအထ က ဗ႔အားျမငတာမ႔ High Tension (HT) Circuits ေတြ လ႔ေခၚၿပး Transformer အထြကကေတာ ဗ႔အားနမ LV Circuits ေတြလ႔ေခၚပါတယ။Cable / Busducts ေတြ အတြက လမးေၾကာငးရာတာ၊ Major Equipments ေတြအတြက သငေတာတ ေနရာ လာထားသတမတ တာ ေတြ က Project Design Phase မာကတညးက ေလလာ ညႏႈငး သတမတ ထားရမာ ျဖစပါတယ။

II. Electricity (Power) Supply Systems LV Distribution Systems ေတြအေၾကာငး က မဆကခင အေျခခ တခ႕က ျပနၿပး မတဆကေပးပါမယ။ Electricity(Power) Supply Systems ေတြ ကျခင ၾကညမယဆရင ေတြ႕ရမာကေတာ၊

A. Power Generation SystemsB. Power Transmission SystemsC. Power Distribution SystemsD. Low-Voltage Systems

Power Plants လ႔ေခၚတ Electrical Power Generators အမးမး ကေန လပစစဓာတ က ထတလပ ႏငပါတယ။ ဒGenerators ေတြ က ေမာငးႏငဘ႔ အတြက prime mover ေတြက ေရန၊ ဒဇယသး အငဂငေတြ၊ ေကာကမးေသြး၊အျခားေလာငစာေတြ Biogasifier ေတြ န႔ Nuclear ေတြ ကအသးျပတ Steam Turbines ေတြ၊ Gas Turbines ေတြသာမက Green Sources ေတြျဖစတ Geothermal, Hydro, Tidal, Wind, Solar, etc. ေတြကေနလညး ရရႏငပါတယ။ဘယကေန ပ ထတထတ၊ ေစးႏႈနးသကသကသာသာ န႔ ျဖန႔ေဝေပးႏင ဘ႔၊ လအပခကအတငး အရညအေသြး ျပညဝတ ပါဝါရႏငဘ႔၊ န႔ ေရရညထတယႏငဘ႔ လအပပါတယ။ ဒါအျပင လျခစတခ အႏရာယ ကငးေဝးေစဘ႔ န႔ ပတဝနးကင အေပၚထခကမႈ နညးေစဘ႔ ေတြ ကလညးထညသြငးစဥးစားရမ အခကေတြပါ။အၾကမး အားျဖင ရငးႏးျမႈပႏမႈ ရ ၅၀% က လပစစထတ စကရေတြ အတြက၊ ၃၀% က ပ႔ေဆာငမႈ အတြက၊ န႔ ၂၀%ကျဖန႔ျဖးဘ႔ အတြက အသးျပရပါတယ။ ေလာငစာဆဘး၊ လညပတစရတ န႔ ျပျပငထနးသမး စရတက လညး annualinvestment cost (တစႏစစာ ရငးႏးျမႈပႏမႈ ေငြ) ရ ၂၃၀% ေလာက က ရႏငပါတယ။Power Station တစခတညေဆာကဘ႔ အတြက ပမးမ Lead Time က ၅ ႏစေလာက လအပပါတယ။ ဒါေပမ InvestmentCost (ရငးႏးျမႈပႏေငြ) န႔ (Operating Cost) လညပတေငြ ေတြက Optimize (အကးအရ ဆး အသးခ) ႏငဘ႔ အတြကExpansion Planning က ၁၅ႏစေလာက ႀကတငေလလာ ဆနးစစမႈျပရပါတယ။ေအာကမာ US. DOE ရ Simple diagram of electricity grids in North America ကေဖာျပထားပါတယ။

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A. Electrical Power Generation SystemsElectric Energy က အျခား Energy Supply Systems ေတြ လ စးပြားေရး အရ တြကေခကကကက န႔အႀကးအကယ သေလာငထားႏင ဘ႔ဆတာ မျဖစႏငပါဘး။ ဒါေၾကာင အခနတငး မာ ထတလပတ ပါဝါ န႔ သးစြ တ ပါဝါမေနဘ႔ လပါတယ။ဒါေၾကာင Power Plant စကရေတြက ထနးခပေမာငးႏင ေနတ System Control Engineer ေတြက သးစြ ေနတပါဝါ န႔ မေအာင ထတလပႏငဘ႔ စမရပါတယ။ Historical Trends ေနာက ၂၄ နာရ အတြငး လအပမ႔ ပါဝါအနညးအမား ပစ က ခန႔မနး ႏငဘ႔ န႔ မနးခက အတငး ထတလပေပးႏငဘ႔ လညး လအပပါတယ။ ရေနတGenerators ေတြန႔ efficiency ေတြေပၚမတညၿပး အသငေတာဆး၊ အကးအျဖစဆး၊ ရႏငေအာင Generatorsဘယႏစခ ဘယလ အစအစဥ န႔ လညပတ ထတလပ မာလညး အစအစဥ ခရပါတယ။ ခေနာကပငး ကြနျပတာေတြေပၚလာေတာ ဒလလပရတာ ပၿပး လြယကလာပါတယ။ System Control Engineers ေတြရ အဓကတာဝနေတြ ကေတာ၊Minimize generation cost (ထတလပမႈ စရတ ေလာခႏငဘ႔)Ensure continuity of supply (အဆကမျပတ ပ႔လႊတႏငတာ ေသခာေစဘ႔၊)ပမန အေျခအေန န႔ ပမန မဟတတ abnormal conditions အေျခအေန အခ႕တြက Generating Units ရoperating constraints အားလးန႔ Transmission Network ရ Limits ေတြ အတြငးမာ ပရေနဘ႔လညးလအပပါတယ။

B. Power Transmission SystemsTransmission Systems ေတြဆတာ က တစေနရာ က တစေနရာ ကပ႔လႊတေပးတ စနစေတြ ကေခၚတာပါ။အသးျပမယ အနားမာ Power Plant ရေနရင ေတာ Transmission Systems ေတြ မလအပေတာတာမ႔အေကာငးဆးေပါ။ ဒါေပမ ဒလျဖစႏငဘ႔ ဆတာက လကေတြ႕မာေတာ ျဖစႏငဘ႔ မလြယပါဘး။ ဥပမာ ၿမ႕လယေခါင မာPower Plant ေဆာကဘ႔ဆတာ က အမားအားျဖင မသငေတာပါဘး။ အလားတပ သးစြႏငတ ဗ႔အားအတငးအႀကးအကယ ထတလပဘ႔ ဆတာလညး နညးပညာအရ မျဖစႏငပါဘး။ဥပမာ 400V န႕ထတလပျဖန႔ျဖးရင 3 to 4 MW ေလာကအထပ လကရနညးပညာ အရသငေတာပါတယ။အလားတပ 22kV န႔ဆ 200 MW, 66kV ဆ 780MW, ေကာရင 230kV သး၊ 5,000 MW ေကာလာရင 400kV စသညျဖငေပါ။

ပ႔လႊတရမ စြမးအင (MW) မားလာတာ န႔ အမ ဗ႔အားျမငမေပးရင Short-circuit current က Breakers ေတြ ရBreaking Capacity က ေကာလြနလာႏငတာ မ႔ ဗ႔အားက ျမငေပးရတာ ျဖစပါတယ။မဟာဓာတအားလငး ေတြက ေျမေပၚ၊ ေျမေအာက ပ႔လႊတရေလ ရေပမ ေျမေပၚကပလႊတရတာ က ကနကစရတသကသာတာရယ၊ သာမန လပသားကၽြမးကငမႈ န႔တင လပႏငတာ ရယ၊ ထနးသမးျပျပင လ႔ လြယကတာရယ ေတြေၾကာင ျဖစႏငရင Over Head Line လ႔ေခၚတ ေကာငးကင ဓာတလငး ေတြက အသးျပၾကပါတယ။ စကာၤပ မာေတာအဓက ေျမေအာက ကေန ပ႔လႊတတာ က သးပါတယ။

C. Distribution Systems Distribution Systems ေတြရ အဓက အလပ ကေတာ လပစစဓာတက လကကားယ၊ (သေလာင ထားလ႔ ေတာမရပ) ခကခငး လကလျဖန႔ ရတ သေဘာမး ပါ။ Large, bulk power sources ကေန လပစစဓာတအား ကလကခရယ၊ တစၿပငတညးမာပ လအပတ ဗ႔အားအမးမး န႕ လကခႏငေလာကတ reliability (ယၾကညစတခရမႈ)န႔အတ သးစြသေတြ ဆ အေရာကျဖန႔ေဝ ေပးရပါတယ။ အသးျပေလ ရတ ဗ႔အားေတြ ကေတာ 3.3kV, 6.6kV, 11kV,22kV & 33kV ေတြ ျဖစၾကပါတယ။ အထကမာ ျပခတ ပအရ North America လ ပါဝါသးအား အရမးႀကးတေနရာမာေတာ 765kV အထ သးတာ က ေတြ႕ရပါတယ။အဓက စဥးစားရမ လအပခကေတြ ကေတာ

Different source to increase reliabilityMinimum voltage variationMinimum supply interruptionMinimum Overall cost consistent with the power qualityFlexible to allow expansion in small increments

D. Low-Voltage SystemsLV Systems ဆတာကေတာ Distribution Voltage က 1000 V ထက နညးတ ဗ႔အား က ဆလတာျဖစပါတယ။အမားအားျဖင 240, 380, 400, 415, 440, 480, 550 န႔ 600 V ေတြပါ။ႏငငအလက သးစြတ အမသး ဗ႔ န႔ Frequency ေတြ က ေလလာႏငဘ႔ အတြက ေကာကႏတ ေဖာျပထားပါတယ။

RegionType(s) ofplug / socket

Voltage Frequency

Australia I 230 V 50 Hz

http://1.bp.blogspot.com/_LvmQKfk1C-4/SZegHkspoII/AAAAAAAAAUE/sFRjOR_lmWE/s1600-h/Elect_grid_NA.JPG

Brunei G 240 V 50 Hz

China (mainland only) A, C, I 220 V 50 Hz

Canada A, B 120 V 60 Hz

France C, E 230 V 50 Hz

Germany C, F 230 V 50 Hz

India C, D, M 230 V 50 Hz

Indonesia C, F, G127 V /230 V

50 Hz

Japan A, B 100 V50 Hz & 60Hz

Korea, South A, B, C, F 220 V 60 Hz

Malaysia G, M 240 V 50 Hz

Mozambique C, F, M 220 V 50 Hz

Myanmar/Burma C, D, F, G 230 V 50 Hz

New Zealand I 230 V 50 Hz

Singapore G, M 230 V 50 Hz

Thailand A, B, C 220 V 50 Hz

United Arab Emirates C, D, G 220 V 50 Hz

United Kingdom G 230 V 50 Hz

United States ofAmerica

A, B 120 V 60 Hz

ႏငငတကာ မာ သးစြတ Voltage/ frequency အခကအလက ေတြ န႔ သးစြေလ ရတ plug / socket အမးအစားေတြက က Mains power systems မာ မျငမးလ႔ရပါတယ။AC power plugs န႔ sockets ေတြရ အေၾကာငးက လညး AC power plugs and socketsမာေလလာႏငပါတယ။

အသးမားတ Frequency ေတြကေတာ 50Hz / 60 Hz ေတြ ျဖစပါတယ။ ဒ Frequency ကေန အဓကသကေရာကတာကေတာ AC Motor ေတြရ လညပတမႈႏႈနး rpm ပါ။ AC motor ေတြရ rpm က Frequency န႔ စမထားတStator ရ သလကဝငရး Pole အေရအတြက န႔ သကဆငတာ မ႔ပါ။ AC motor ေတြရ ideal rpm ကျပေလ ရတformula က ၾကညရင။rpm = (120 x F) / P F: Frequency (Hz), P: no. of PolesRpm ကြာျခားလာတာန႕ အမ ဒ motor က ေန ေမာငးေပးရတ fan, pumps, compressors, etc. ေတြ ရ

Mechanical Power ကလညး n3 (Tube) တကလာမာ ျဖစပါတယ။ အလားတပ 60Hz န႔ ေရြးထားတစကပစၥညးေတြ က 50Hz န႔သးရင Capacity စြမးအား အျပညရမာ မဟတပါဘး။ အထးသျဖင HVACequipments ေတြ န႔ Pumps ေရြးခယ ဘ႔ Engineering Data ေတြက ဖတ တ အခါ 50Hz လား 60Hz လားေသခာစစေဆးရမာ ျဖစပါတယ။စကာၤပ ႏငင မာ LV Systems ဆတာ က Three-phase, four-wire system ျဖစၿပး between line-to-line400V ရၿပး between line-to-neutral ကေတာ 230V ပါ။ ဒါက distribution voltage တငမဟတပအသးအေဆာင appliance အမားစရ လအပတ utilization voltage လညးျဖစပါတယ။

III. AC FundamentalsA. Sin Wave and Root Mean Square Value

AC ဗ႔အား က Frequency တစခန႔ အေပါငးအႏတ ေျပာငးလေနပါတယ။ Sinusoidal Voltage အေနန႔ပါ။Voltage ေျပာငးတာ န႔ အည Current ကလညးေျပာငးပါတယ။

http://4.bp.blogspot.com/_LvmQKfk1C-4/SZgky3aWGlI/AAAAAAAAAUk/Zqk62QXxXQU/s1600-h/Elect_SineWave.JPG

http://en.wikipedia.org/wiki/AC_power_plugs_and_sockets

http://www.blogger.com/%20http://en.wikipedia.org/wiki/Mains_power_systems

AC power ေတြ က တြကတ အခါ maximum အစား ပမးမ voltage န႔ current ကအေျခခ ဘ႔လပါတယ။ Rootmean square value (rms) လ႔လညး ေခၚပါတယ။ Sine wave တစခရ rms value က max value ရ 1/√2 (~0.707) ေလာကရပါတယ။Vrms = Vmax / √2

Irms = Imax / √2

တြကခကတ အခါမာေရာ rms value ကပသးပါတယ။ ဒါေၾကာင rms မပါေပမ rms value ကသးမနးေတာသရပါမယ။

B. Complex Powerေနာကတစခ သရမာ က AC power ေတြက Complex Power ျဖစေနတာကပါ။ သ႕မာ Real Power & ReactivePower ဆၿပး အပငးႏစခ ပါပါတယ။ Voltage န႔ Current Wave ေတြက တစထပတညး မကပ အခနတစခကြာေနတာ (Leading or Laging) ျဖစေနတာပါ။

ဒါေၾကာင Power Factor ( p.f ) လ႔ေခၚတ real power ရအခးအဆ ကေဖာျပတ Term တစခ ကသတမတ ၾကတာျဖစပါတယ။

Power Factor ( p.f ) = Real Power / Complex Power = cos φPower factor ( p.f )က ဘယေတာမ တစ (1) ထကမေကာႏငပါဘး။ တစရရင အေကာငးဆး လ႔ သတမတပါတယ။

i. Real Power, P (watts):P = V × I × cos φ

ii. Reactive Power, Q (vars):Q = V × I × sin φ

iii. Complex Power, S (watts):S = V × I = P + jQ

ဒလျဖစရျခငး အေၾကာငးရငး ကေတာ Circuit ရ Properties ေတြ ထမာ Resistance သာမက Reactance ကျဖစေပၚေစတ Capacitance ေရာ inductance ေတြပါပါဝင ေနတာေၾကာငပါ။

Inductance ဆတာက လပစစသလကညႈ႕ကြင ေတြ ပါဝငတ မးေခာငး ballast လ motor, transformer ေတြလစကပစၥညးေတြ က ေနျဖစေပၚတ ဂဏသတပါ။ အေဆာကအအ တငးလလ မာ ဒစကပစၥညးေတြ က အသးျပေလရၾကတာမ႔အမားအားျဖင Load မာက ဒလ Inductance ပါဝငေလ ရၿပး သ႕ေၾကာင ကသြားတ Power Factor ( p.f)က 1 န႔ အနးဆး ရေအာင ျပနျမင ေပးဘ႔ အတြက Capacitor Bank ေတြ ထညသြငးေပးၾကတာ ျဖစပါတယ။ ဒလPower Factor Correction လပဘ႔ အတြက Shunt Reactor Bank န႔ Capacitor Bank ေတြပါဝငတတသလအျခားနညးေတြ လညးရပါတယ။ ပမ ရႈတေထြးတ Non-Linear Distortion (or) Harmonic က ျဖစေစတRectifier (AC to DC converters) ေတြ ျဖစတ fluorescent lamp, electric welding machine, or arcfurnace ေတြ ပါလာတ အခါ ပၿပး ထနးရ ခကပါတယ။ Inverter န႔ VSD (Variable Speed Drive) ေတြ လညး

http://1.bp.blogspot.com/_LvmQKfk1C-4/SZgkzQrVpDI/AAAAAAAAAUs/Uc_pOMXDgBY/s1600-h/Elect_CplxTriangle.JPG

http://4.bp.blogspot.com/_LvmQKfk1C-4/SZgky3aWGlI/AAAAAAAAAUk/Zqk62QXxXQU/s1600-h/Elect_SineWave.JPG

http://2.bp.blogspot.com/_LvmQKfk1C-4/SZgkztvZejI/AAAAAAAAAU0/TIDrhOI-BLk/s1600-h/E_RstCapInd.JPG

ဒအမးအစား ထ မာ ပါဝငပါတယ။ အေသးစတ သခငရငေတာ Power Factor Correction Units ေတြအေၾကာငးက ရာေဖြ ေလလာႏငပါတယ။ဒလ Reactance ေတြ ပါဝင ေနတတ တာမ႔ AC တြကခကမႈ ေတြ က Faradays Law (I = V /R န႔ တကရကတြကခက လ႔မရေတာပ Resistace: R ေနရာ မာ Impedance: Z က အစားထး အသးျပရတာ ျဖစပါတယ။Impedance (Z) ဆတာ ကေတာ the ratio of phasor voltage to phasor current ပါ။Z = V /I

Resistor: ZR = R

Capacitor: ZC= 1 / ( jωC ) = jXC

Inductor: ZL = jω L = jXL

Where;C = capacitance (farads)L = inductance (henrys)ဒမာပါတ j ဆတာ ကေတာ Complex index ျဖစတ √-1 ပါ။

Power factor ( p.f ) က Inductive Circuit မာဆရင Lagging (current lags the voltage) ျဖစၿပးCapacitative Circuits ဆရငေတာ Leading (current leads the voltage) ျဖစပါတယ။

C. Design Calculation Formulaei. Power, P (kW):

Single Phase Load:P = V × I × p.f

Three Phase Load:P = √3 × V × I × p.f

ii. Design Current, I (A):Single Phase Load:I = kW x 1000 / (V × p.f )

Three Phase Load:I = kW x 1000 / (√3 × V × p.f )

Three Phase Motor :I = kW x 1000 / (√3 × V × p.f × Eff )

Discharge Lighting :I = Wattage of Lamp x 1.8 / V

Motor Starting Current:Manufacturer’s Data မရႏငတ အေျခအေန မာ ခန႔မနးဘ႔ အတြက

DOL Starter:Istarting = 7 × Ifull load for 10s

Other Starter:Istarting = 4 × Ifull load for 15 s

iii. Voltage Drop (V)Vdrop = [ (r cos φ + x sin φ ) / 1000 ] × I × Length

IV. Power Grids, Preliminary Load Estimates, Basic Metering SchemeA. Power Grids

အေဆာကအအ ေတြ ေဆာကလပတ အခါ အေရးႀကး တ အခက ကေတာ လအပတ လအပတ Power န႕ PowerQuality က အဆကမျပတ ရရႏငဘ႔ ပါ။ ဒလ ႏငေအာင အေဆာကအအ မေဆာကခင ထ က စၿပးေလလာျပငဆငမႈ ေတြ လပရပါတယ။ပါဝါျဖန႔ေဝတ Power Grid / Utility Company န႔ဆကသြယ၊ လအပခကေတြ ကတငျပ၊ ရေနတ Power GridInfrastructure ေတြန႔ ပါဝါ ဆကသြယ ရ႐ႏငမႈ ေတြ က ေလလာ ၿပး ေဆြးေႏြးမႈ၊ ညႏႈငးမႈ ေတြ လပရသလေဆာကေနဆ အခနမာ လညး လအပသလ တငျပ ညႏႈငးမႈ ေတြ လပေဆာငရပါတယ။ ဒလ အဆငဆငပးေပါငးေဆာငရြက မႈ ရမ သာ အေဆာကအအ ေဆာကၿပးတ အခနမာ အခနမ လပစစ ပါဝါ ရရမာ ျဖစပါတယ။တးတကေနတ ႏငငေတြမာ အေဆာကအအ တစခ က ေဆာကလပၿပးစး သြားေပမ လပစစ ပါဝါ မရေသးမခငး

အသးမဝငလ ပါဘး။ ေရာငးလ႔မရ၊ ေနလ႔မရ၊ ငားလ႔ မရ န႔ေပါ။ ဒါေၾကာင အခနမ ပါဝါ ရဘ႔ က အငမတန အေရးႀကးပါတယ။

လပစစ ပါဝါ ေလာကထားရတ Electricity Supply Application Process ေတြက စနစတက ျဖစေစဘ႔ အတြကPower Grid / Utility Company ေတြ က Electricity Supply Application Handbook ေတြ ရကႏပထတေဝ ထားေလရပါတယ။ ဒစာမာ ေတာ ေလလာစရာ နမနာ အျဖစ Internet ကေန အလြယတက Downloadလပယ ႏငတ မေလးရား ႏငင TNB ရ "Electricity Supply Application Handbook", TNB Malaysia ကညြနးလပါတယ။ ဒစာအပ ထ မာ သးစြသ ဘကကေရာ၊ ပါဝါျဖန႔ေဝသ ဘကကေရာ ရတ တာဝန ေတြ ကရငးရငးလငးလငး ေဖာျပထားပါတယ။ သးစြသဘက က စနစကဘ႔ လအပသလ ျဖန႔ေဝသ ဘက ကလညး မးမနဘ႔တာဝနယရပါတယ။ ထနးသမးလ႔ မရတ အေျခအေန (ဥပမာ။ ။ မနတငး အႀကးအကယ တကတာ မး၊ ေျမၿပတာ မး၊ )ကလြရင အျခားအေျခအေန ေတြ မာ ခနခန မျပတေတာက ဘ႔ န႔ ျပတေတာက ခရင ဘယႏနာရ အတြငး ျပနရေအာငလပေပးမယ ဆတ အာမခခက ေတြ ေပးရပါတယ။မးက ျဖတခငသလျဖတ ေပးခငသလ ေပး ၊ မးအားတကတကကက၊ ဘယသဘာျဖစျဖစ ဆၿပး ထငရာစငးခြင မရတာ က ေတြ႕ရပါလမမယ။ပထမ အေဆာကအအ မာ သးမ Load/ Maximum Demand န႔ Load Characteristics ေတြ က ခန႔မနးရပါတယ။ ၿပးမ Power Grid Company ကတငျပရငး အနးစပဆး ပါဝါလငး က ဘယမာလ။ Voltage က HT(High Tension) / Medium Voltage လား LT (Low Tension) လား၊ ဘယႏ ဗ႔အားေတြ ရႏငလ ဆတအခကအလက ေတြ ကလညး ေတာငးယရပါတယ။ေပးမာက ဗ႔အား အျမင ဆရင ကယလခငတ ဗ႔အား ရဘ႔အတြက Transformers လပါတယ။ ေနာက PowerCompany's အတြက Switch Gear ထားဘ႔ အခနးေနရာ ေဆာကေပးရတတပါတယ။ ဒ အခနး ရ အရြယအစားလအပခက န႔ ထားရမ ေနရာ ေတြ က လညး သတ႔ Handbook မာထညသြငး ေဖာျပေလ ရၿပး လကနာဘ႔ လညးလအပပါတယ။

ကယသးခငတ ဗ႔အား (ဥပမာ အမသးဗ႔အား) တနးရႏငရင Transformers မလသလ HT Switchgear လညးမလအပ ပါဘး။ ေနရာလညးသကသာပါတယ။ ဒါေပမ Tariff ယနစတစခ (per VA) အတြက ကနကေငြေတာပႏငပါတယ။

Power Company's ရ႕ေပးႏငတ ဗ႔အားက က ကယလခငတ Load/ Maximum Demand ေပၚမာ လညး မတညတာမ႔ ကယလခင သလ ေပးမာ ေတာ မဟတပါဘ။ Negotiation ေတာ အနညး န႔ အမား လပၾကည ႏငပါတယ။လအပတ အေဆာကအအ ရ Maximum demand (Load) ေပၚမတညၿပး ေပးႏငတ Supply Voltage ေတြ ကလညး သတမတ ေဖာျပ ထားေလရပါတယ။

MalaysiaLow Voltage

i. 240V, 50Hz, Single-phase, two-wire, up to 12 kVAii. 415V, 50Hz, Three-phase, four-wire,up to 45 kVAiii. 415V, 50Hz, Three-phase, four-wire, C.T. metered, up to 1,000 kVA

Medium Voltage & High Voltagei. 11 kV, 50Hz, Three-phase, three-wire, 1,000 kVA maximum demand and

aboveii. 22 kV or 33kV Three-phase, three-wire, 5,000 kVA maximum demand and

aboveiii. 66kV, 132kV and 275kV, Three-phase, three-wire, exceptionally large load

of above 25 MVASingapore

i. 230V, 50Hz, Single-phase, two-wire, up to 23 kVAii. 400V, 50Hz, Three-phase, four-wire, up to 2,000 kVAiii. 22 kV, 50Hz, Three-phase, three-wire, up to 30,000 kVAiv. 66 kV, 50Hz, Three-phase, three-wire, greater than 30,000 kVA

ေနာက ပစတခခင Alternative Source ေနာကတစခ ရႏင၊ မရႏင လညး ညႏႈငး ႏငပါတယ (ေငြေတာပကနမယ)။ေနာက Metering Scheme လ႔ေခၚတ မတာေတြ က ဘယလ အစအစဥ န႔ တပဆင မာလညး ဆတာ က လညးသတမတညႏႈငး ရပါတယ။

B. Preliminary Load EstimatesProject ရ လအပခက က လကလ႔ သးစြမ လပစစဓာတအား Load က အၾကမးဖငး လာထားရပါတယ။Experienced Electrical Engineer ေတြ အတြက ကေတာ ဒါက ထမငးစားေရေသာက အလပပါ။ ခပဆငဆငတတ အျခား Project ေတြ ကေနလညး မျငမး ႏငပါတယ။ Utilities Company ေတြ မာလညး ဒလ သးအားStatistics ေတြရပါတယ။ TNB ကေတာ မေလးရား ႏငင က သးစြသ အမးအစား အခ႕ရ အသး Statistics က ဒလေဖာျပထားပါတယ။

Table 3-1: Range of maximum demand (M.D) for domestic consumer sub-classes or premises

No: Type Of PremisesMinimum(kW)

Average(kW)

Maximum(kW)

1Low cost flats, single storeyterrace

1.5 2 3

2Double storey terrace orapartment

3 4 5

http://www.tnb.com.my/cms/uploadfile/Highlight/ESAH.pdf

3 Single storey, semidetached 3 5 7

4Single storey bungalow & three-room condominium

5 7 10

5Double storey bungalow & luxurycondominium

8 12 15

Table 3-2: Range of maximum demand (M.D) for types of shop-houses

No: Type Of PremisesMinimum(kW)

Average(kW)

Maximum(kW)

1 Single storey shop house 5 10 15

2 Double storey shop house 15 20 25

3 Three storey shop house 20 30 35

4 Four storey shop house 25 35 45

5 Five storey shop house 30 40 55

ဒအခကအလကေတြ က မကစမတ သးရမာေတာ မဟတပါဘး။ မသးခင ကယ Project ရ Nature န႔အေဆာကအအ ရ အမနတကယ လအပခက န႔ ကကညမႈ ရမရ ဆနးစစရပါတယ။Project ရ လအပခက က လကလ႔ သးစြမ လပစစဓာတအား Load က အၾကမးဖငး လာထားရပါတယ။ဒလ ခန႔မနးတ အခါ သးစြတ အသးက လကၿပး ထပဆင ခြျခားမႈေတြ လညး လပရပါတယ။

Power သးဘ႔ ဆရငHome / Office AppliancesProcess Equipments (Client ဆကေန ေတာငးယရပါမယ။)Building Services Equipments (such as pumps, fans, chillers, elevators/escalatormachines, and extra low voltage systems)Essential Services ( အေရးေပၚ မဟတေသာလညး အေျခခ မရမျဖစ လအပခက မား)Emergency Services ( Fire Services, Emergency Lighting etc. (အေရးေပၚ အေျခအေနလအပခက မား)

Lighting (မးထြနးဘ႔) ဆရငလညးGeneral LightingSpecial / Task LightingsEmergency LightingOutdoor / Street Lighting

အစရသျဖင ထပမခြျခားရပါတယ။ဒါမ Circuit Arrangement လပတ အခါ န႔ Emergency Load ေတြ ကလညး စနစတက တြကခကႏငမာျဖစပါတယ။

C. Basic Metering Schemeပမနအားျဖင လအပတ Meter အားလး က Power Grid က သ႕စရတ န႔ သ တာဝနယ ၿပး တတဆငေပး ရေလရပါတယ။ လအပတ Maintenance ကလညး Power Grid ကပတာဝန ယရပါတယ။ မတာထားဘ႔ ေနရာ၊ Board,compartments, kiosks, အစရတာ ေတြ ကေတာ သးစြသ က တာဝနယ ရေလရ ပါတယ။မတာ Faulty ျဖစခရင Grid ကပ ျပျပင ေပးရေလ ရတယ။ ထခက ပကစးခ ရငေတာ သးစြသ ကသ႕ ပေရာဂမပါေၾကာငး သကေသ မျပႏငရင ကနကစရတ က ကခရပါလမမယ။Master and Sub-Metering Scheme

Multi-tenanted premises လ႔ေခၚတ သးစြတ သ အမးမး ရေနတ အေဆာကအအ ေတြ မာ Master andSub-Metering Scheme လ႔ေခၚတ မတာမႀကး န႔ ထပဆင မတာငယ ေတြ ပါတ အတြ က သးႏငပါတယ။ဒလသးတ အခါ tenant တစခစ က သငေတာတ appropriate tariff န႔ မတာခ ေတာငးခ ႏငပါတယ။Master Meter ရ ယနစထ က Tenants ေတြ သးတ ယနစ က ႏတလက ၿပး ကနတာကOwner/Developer/Landlord ရ အသးမ႔ အဒ မတာခ က ေတာ Owner /Developer /Landlord ကေတာငးခ ပါလမမယ။တစခါတစရ Owner/Developer/Landlord က High Tension ယ၊ ၿပး Low tension ခၿပး ျဖန႔ေဝတအခါ သ႕အတြက အခြငအေရး အခ႕က လညး Grid ကေပးတတပါေသးတယ။

Tariffs (မတာခ ႏႈနးထားမား)Electricity Supply Application ေတြက စဥးစားတ အခါ ဂရစက ရမ အခကတစခ ကေတာ Tariffsလ႔ေခၚတ မတာခႏႈနးထား ေတြပါ။ သးစြတ Tenants ရ အမးအစား (သ႔) အသးျပပ Application ၊ သးစြတအခန (ေန႔၊ည နာရသတမတခက)၊ Voltage န႔ သးစြတ Power န႔ Low Voltage , High Tensionစသညျဖင အေနအထား က လကၿပး သတမတခက ေတြ ရႏငပါတယ။တးတကေနတ ႏငင အမားစ မာ စးပြားေရးအတြက ေန႔ပငးသးစြ တ Power ကမား ေလရတာ မ႔ ပၿပးေတာေစးႀကး ေလရပါတယ။ ညပငးက ပသကသာႏငပါတယ။ ဒါေၾကာင Air-conditioning systems ေတြအတြက Thermal Storage System လ႔ေခၚတ ညပငးပါလညၿပး သေလာငထားတ Chilled watersystem ေတြ သးတ အခါ ေစးပခ ေစႏငပါတယ။

မေလးရား ႏငင ရ မတာခ ႏႈနးထား သတမတပ က ေအာကမာ ေဖာျပထားပါတယ။ March 2009 အရ ပါ။

A Tariff A- Domestic Tariff

First 200 kWh (1 - 200 kWh) per month 21.8 sen/kWh

Next 800 kWh (201 - 1,000 kWh) per month 28.9 sen/kWh

Over 1,000 kWh (1,001 kWh onwards) per month 31.2 sen/kWh

The minimum monthly charge is RM3.00

B Tariff B - Low Voltage Commercial Tariff

For all kWh 32.3 sen/kWh


C1 Tariff C1- Medium Voltage General Commercial Tariff

For each kilowatt of maximum demand per month 19.5 RM/kW



C2Tariff C2 - Medium Voltage Peak/Off-Peak CommercialTariff

For each kilowatt of maximum demand per monthduring the peak period

29 RM/kW

For all kWh during the peak period 23.4 sen/kWh

For all kWh during the off-peak period 14.4 sen/kWh


D Tariff D - Low Voltage Industrial Tariff

For all kWh 29 sen/kWh


Ds Tariff Ds – Special Industrial Tariff

(for consumers who qualify only)



E1 Tariff E1 - Medium Voltage General Industrial Tariff




E1s Tariff E1s – Special Industrial Tariff





E2Tariff E2- Medium Voltage Peak/Off-Peak IndustrialTariff


24.4 RM/kW




E2s Tariff E2s – Special Industrial Tariff



21 RM/kW




E3 Tariff E3- High Voltage Peak/Off-Peak Industrial Tariff


23.4 RM/kW




E3s Tariff E3s– Special Industrial Tariff



18.5 RM/kW




"PEAK PERIOD" means the period between 0800 hours and 2200 hours."OFF-PEAK PERIOD" means the period between 2200 hours and 0800 hours.

March 2009 ရ ႏႈနးထားပါ။ ႏႈနး အတကအက ရႏငပါတယ။RM ဆတာကေတာ မေလးရား ႏငင သးေငြ Ringgit Malaysia ကဆလတာ ျဖစၿပး 1 RM = 100sen (ျပား) ရပါတယ။ပၿပး အေသးစတ သခငရင TNB Website မာ Tariff Booklet Download လပၿပး ေလလာႏငပါတယ။

Singapore ႏငငရ tariff ကသခငရင ေတာ Singapore Power Website မာသြားေရာက ရာေဖြ ေလလာႏငပါတယ။ 01 April 2009 အတြက tariff rate ေတြကေတာ ၊

DescriptionTariff(with 7% GST)

LOW TENSION SUPPLIES, DOMESTIC

All units 19.29 ¢/kWh

LOW TENSION SUPPLIES, NON-DOMESTIC

All units 19.29 ¢/kWh

HIGH TENSION SMALL (HTS) SUPPLIES

Contracted Capacity Charge 7.45 S$/kW/month

Uncontracted Capacity Charge 11.17 S$/chargeable kW/month

kWh charge

Peak period(7am to 11pm) 16.54 ¢/kWh

Off-peak period(11pm to 7am) 9.71 ¢/kWh

Reactive power Charge 0.63 ¢/chargeable kVARh

HIGH TENSION LARGE (HTL) SUPPLIES



kWh charge



http://www.tnb.com.my/tnb/tariff/download/booklet_bi.pdf

http://www.singaporepower.com.sg/

http://www.tnb.com.my/tnb/tariff/index.htm


EXTRA HIGH TENSION (EHT) SUPPLIES



kWh charge




-- ဆကရန --ေအာက က စာ ေတြ ကေတာ အၾကမးေရးလကစပါ။

V. Major ComponentsLV system န႔ earthing က install လပတ အခါ ဘယ appliance မာပ fault ျဖစျဖစ၊ လေတြ ထမ ကငမ ႏငတ ေနရာအားလးမာ အႏရာယ ျဖစႏငေလာက တ ဗ႔အား အထေအာင တကမလာ ေအာင စစဥရပါမယ။ဒါအျပင Circuit တငးက overload , earth fault န႔ short-circuit currents ေတြက ေန လလေလာကေလာက ptotectလပေပးရပါမယ။

Electrical Installation မာ ထခကဒါဏရာ ရမႈ အမားစ ကျဖစေစတာ က Electrical Wiring က မကြမးကင တElectrical personnel ေၾကာငပါ။Equipments ေတြ၊ Conductor ေတြ၊ Protective Devices ေတြ န႔ accessories ေတြ က စစစေရြးခယ တ အခါစြမးေဆာငရည Performance, capacity, efficiency န႔ ဒါဏခႏငမႈ စြမးရည ေတြ ျဖစတ rating, short-circuit ratingေတြ အျပင Electrical Distributions System ထမာ တပဆငထားတ စက ပစၥညး Major Equipments ေတြ Cables,busbars conductors ေတြ န႔ Protect devices ေတြက ၊ သးစြမ electrical appliances ေတြ၊ အျခား BuildingSystems ေတြ န႔ ရေနတ Occupants လေတြ က အႏရာယ ကငးေဝး ရေအာင ေသေသခာခာ ဂရစက စဥးစား ေရြးခယေပးရပါမယ။

Design / Installation မာ အဓက စဥးစားရမ အခကေတြ ကေတာအႏရာယ ကငးကငး အလပလပ ႏငဘ႔၊ Maintenance လပႏငဘ႔၊ လလယႏငဘ႔ Withdrawable Parts ေတြ ကလြတလြတလပလပ အႏရာယ ကငးကငး ထတႏင၊ သြငးႏငဘ႔Equipment ပစၥညး အထတအသြငး၊ အလအလယ လပႏငဘ႔၊Short Circuit ဒါဏ ခႏငစြမးရည အတြငးရဘ႔၊Temperature (Conductors/ Equipments)ခႏငရည အပခန ထက ပတကမလာဘ႔၊Voltage Drop Limits က သတမတခက အတြငး ထနးထားႏငဘ႔၊Disturbance (Magnetic) ေတြ က ကန႔သတႏငဘ႔၊Phase တစခစ ကဆြ တ Ampere ေတြ အတတႏငဆး Balance ျဖစေစဘ႔ Circuit ေတြ မာ စစဥေပးဘ႔။Total Safety က ေသေသခာခာ စဥးစားထညသြငး ေပးထားဘ႔

1. High Tension (Medium Voltage) Switchgear in Consumer Substationအေဆာကအအ ပငရင ရ Substation မ႔ Consumer Sub-station လ႔ေခၚတာ ပါ။ HT Switch Gear ျဖစၿပးအဓက ပါဝငမာ က High tension အတြက သငေတာတ Circuit Breaker န႔ Control Components ေတြျဖစၾကပါတယ။ Gas Insulated န႔ Air Insulated Switchgear ေတြ က အသးမားၿပး အထမာ ပါဝငတ CircuitBreaker ကေတာ SF6 Insulated Circuit Breaker (or) Vacuum Circuit Breaker ျဖစႏငပါတယ။Switchgear : An assembly of main and auxiliary switching apparatus for operating, regulating,protection or other control of an electrical installation.A circuit breaker is a safety device enabling switching and protection of electrical distributionnetworks.ေအာကမာ HT Switchboard ရ Schematic က HT Single Line drawing တစခ ကေန extract လပၿပးေဖာျပ ထားပါတယ။

အဝင ကေတာ Power-Grid Substation ကျဖစၿပး အမားအားျဖင Busbar conductor န႔ ျဖစေလ ရပါတယ။ ဒမာသးထား တာ က GIS (Gas Insulated Circuit Breaker) ျဖစပါတယ။ သရ Characteristics ေတြ ကေတာ

3P: Three Poles (For 3 Phase Conductors)24kV: Rated Voltage ျဖစၿပး 24kV အတြက သငေတာရမယ လ႔ ဆလပါတယ။800A: Rated Current ပါ။ ဒ Current က continuously carry လပႏငရပါမယ။25kA, 3s: Short Circuit Capacity(Rated Breaking Capacity)

Control & Monitoring လပဘ႔ အတြက အျခား Current Transformers ေတြ န႔ components ေတြ ကလညးေတြ႕ရပါလမမယ။ ဒမာ အထြက ကေတာ Transformer ဆက သြားရမာ ျဖစပါတယ။ ဒမာ သးထားတာက 22kV HT Cableျဖစပါတယ။ Cable အစား Busbar Conductor ကလညး သးႏငပါတယ။ေအာကမာ HT Switchboard ေတြ ရ နမနာ ပေတြ က ေဖာျပ ထားပါတယ။ Catalog & Technical Data ေတြ န႔အေသးစတ က ေလလာခင ႏငဘ႔ အတြက ထတလပသ အခ႕ ရ Link ေတြ ကေတာ

Schneider ElectricSquare D by Schneider ElectricABB

http://2.bp.blogspot.com/_LvmQKfk1C-4/ScyfETGKc1I/AAAAAAAAAZA/z0zuNRUe82E/s1600-h/EL-HT-HTSB.jpg

http://3.bp.blogspot.com/_LvmQKfk1C-4/ScyfEruShPI/AAAAAAAAAZI/Cq6ok8lsTJ0/s1600-h/EL-HT-HTSB_p0.jpg

http://ecatalog.squared.com/

http://www.schneider-electric.com/

http://www.abb.com.sg/

2. Transformersဒမာ သးတ Transformer ရ တာဝနက medium voltage ကေန အမသး၊ စကရသး Equipment န႔ ElectricalAppliance ေတြ အတြက သငေတာတ voltage ရေအာင step down လပေပးဘ႔ပါ။Transformers : A device that is used to convert electricity energy from higher a.c voltage todesire consumer voltage (step down) or vice versa.အဓက အသးမား တာ ကေတာ Liquid (Mineral Oil or Fire resistance Liquid Filled) န႔ Dry Type (CastResin) ေတြ ျဖစၾကပါတယ။ Oil Type Transformer ေတြ အတြက ဆယတ အခါ၊ ေဖာကထတဘ႔ လတ အခါ ဆေလာက မျပန႔ေစဘ႔ အကန႔ (Oil pit) လအပပါတယ။ Dry Type Transformer ေတြ မာ သတထား ဘ႔ လအပတာကေတာ Temperature Rise class ပါ။(Class A:60°C, E:75°C, B:80°C, F:100°C, H: 125°C, etc.)အမားအားျဖင Indoor ထားေလ ရတာ မ႔ လေလာကတ Ventilation န႔ Fire Protection System ေတြ ပါဝငရပါမယ။ လအပတ Ventilation Rate (or) Cooling Load ကတြက တ အခါ Transformer Loss (ပမးမ 2.5%)ေလာကန႔ load factor (0.8) ေတြ ကထည သြငး စဥးစားေပးပါ။ Mechanical Ventilation ပေပးမယ ဆရငေတာအျပငက အပခန ထက 5°C (9°F) ထက မပေအာင စဥးစားၿပး အတတႏငဆး Transformer ရ အေပၚတတ ကေနExhaust က ဆြထတေပးပါ။ေအာကမာ Transformer ရ Schematic က HT Single Line drawing တစခ ကေန extract လပၿပး ေဖာျပထားပါတယ။

http://3.bp.blogspot.com/_LvmQKfk1C-4/ScyfKZyPcCI/AAAAAAAAAZo/51ihO7rwcrA/s1600-h/EL-HT-EARTH_p0.jpg

http://2.bp.blogspot.com/_LvmQKfk1C-4/ScyfEpzNcSI/AAAAAAAAAZQ/8zQ0_3_72NI/s1600-h/EL-HT-HTSB_p1.jpg

%Z ဆတာကေတာ Impedance ရ တနဘး Limits က ေပးထား တာပါ။

3. Standby Emergency Power Generatorsအေရးေပၚ အေျခအေန မာ လအပမ Life Safety Systems ေတြ န႔ မးျပတရင ဆးရႈးမႈ အမားႀကးရႏငတစကပစၥညး ေတြ အတြက လအပမ standby power ေပးဘ႔ အတြက တြကခက တပဆငထားတ (အမားအားျဖင)ဒဇယ Standby Power Generator ကေခၚတာပါ။Standby Emergency Power Generators : Electricity Generator set driven by prime mover and ofsufficient capacity to supply circuits carrying emergency loads with suitable means forautomatic starting of the prime mover on failure of normal service

4. Main Switchboard (MSB)Switchboard : An assembly of switchgear with or without instruments, but the term does notapply to groups of local switches in final circuits.

5. Emergency Main Switchboard (EMSB)Utility Network ကဝငလာတ မးျပတေတာက ခ ရင Standby Back-up Electricity ကေန အလအေလာကလပစစပါဝါ ေျပာငးေပးႏငဘ႔ တပဆငထားတ Switchboard ပါ။ အေရးအႀကး ဆး ကေတာ လေတြ ရ အသက lifesafety က ေစာငေရာကဘ႔ တပဆငထားတ Fire Protection, Smoke control systems, EmergencyLighting န႔ Emergency evacuation support systems ေတြအတြက မရမျဖစ လအပပါတယ။Emergency Power : To supply electrical power automatically in the event of failure of thenormal supply to protect equipment essential of safety to life

6. Control Systems

- To be continued -

7. Fuse, Circuit Breakers, Protective Devicesi. The rated current (IN) of a circuit breaker is the current that it can carry continuously, generally

for a duration of more thon eight hours. The rated current must not cause a temperature rise inexcess of the specified values when the ambient temperature is between -5°C to 40°C.Different temperature rise limits are specified for different ports of a circuit breaker. A circuitbreaker will not operate (trip) if the current passing through if is 105% to 113% of its ratedcurrent. It will take one to two hours to trip if the current passing through it is 130% to 145% ofthe rated current.

ii. The breaking capacity of a circuit breaker is the maximum current (in r.m.s.) that flows throughthe breaker and the breaker is capable to interrupt at the instant of initiation of the arc during abreaking operation at a started voltage under prescribed conditions. The breaking capacity isusually expressed in kA or MVA. Typical values range from 3 kA to 43 kA.

iii. The making capacity of a circuit breaker is the maximum current that will flow through thebreaker and the breaker is capable of withstanding of the instance during a closing operationat a stated voltage under prescribed conditions. Typical values range from 7.4 to 2.2 times ther.m.s. value of the breaking capacity.

http://3.bp.blogspot.com/_LvmQKfk1C-4/ScyfE1jdJZI/AAAAAAAAAZY/ZXYTVbM9YE4/s1600-h/EL-HT-TX.jpg

http://4.bp.blogspot.com/_LvmQKfk1C-4/ScyfExSy-MI/AAAAAAAAAZg/O5zGeHUV7Cw/s1600-h/EL-HT-TX_p0.jpg

Miniature Circuit Breaker (MCB)Molded Case Circuit Breaker (MCCB)Air Circuit Breakers (ACB)Residual Circuit Operated Circuit Breakers (RCCB)

8. Earth fault protection

VI. Cable Sizing / Voltage DropConductor (Cable Sizing) အတြက အဓက နားလညရမာ ေတြ ကေတာ။

Schedule of Method of Installation of CablesCorrection Factors

For cables more than one circuitMineral insulated Cables installed on perforated trayCable installed in enclosed TrenchesTemperature (Operating and Ambient)

Conductor Current-Carrying Capacity and Voltage Drop CablesCircuit Breaker CharacteristicsLoad Characteristics (e.g. Motor Starting, Running etc.)

ဒအေၾကာငး န႔ ပတသကၿပး စကာၤပ ႏငင က NTU (Nanyang Technological University), Electrical EngineeringDepartment ရ Head တာဝနယ ခဘးတ Professor CY Teo ေရးသားထားတ "Principles and Design of LowVoltage Systems" မာရငးျပထားပါတယ။ ဒစာအပက ဝယယႏငမ ေနရာ ကေတာ

Clementi Book Store450 Clementi Avenue 3 #01-297, Singapore 120450Phone: 6776-2146| Fax: 67742362Opening Hours: Monday to Friday 9:30 am to 7:00 pm; Saturday 9:30 am to 6:00 pmမသြားခင stock ရမရ ဖနးဆကေမးပါ။

Prof CY Teo က Consultant ေတြ သးဘ႔ Program ေတြ က လညး develop လပခ ပါေသးတယ။ ဒ Program ေတြအေၾကာငးက Byte Power Publication Website မာ သြားေရာက ၾကညရႈ ႏငပါတယ။

VipCoda is a computer program developed for consultant and owner to design and assesselectrical system in Buildings and the completed design can be automatically plotted andexported to AutoCAD by another program SmartDraw.VipCrop is another program for the simulation of HT network operation including Load Flow,Fault Current Calculation and Protective Relay Modeling. It is mainly used for HT networkplanning and analysis for new network, operational planning and switching simulation forexisting network and also for pre-fault or post fault network analysis and on how to restoresupply during fault conditions.VipCag is another program for the grading of over current and earth fault relays includinggraphical presentation in log-log scale for fault current and relay operating time.

VII. Basic Design

- To be continued -

VIII. Regulations

- To be continued -

Manufacturers' LinksSchneider ElectricSquare D by Schneider ElectricABB

http://ecatalog.squared.com/

http://www.abb.com.sg/

http://www.byte-power.com/

http://www.schneider-electric.com/

MEIDEN (Energy)MEIDEN (Singapore)Cummins Power GeneratorsHenikwon BusbarTaisin Cable

References:1. "Regulation for Electrical Installations", 16th Edition, IEE Wiring Regulations, 1991.2. ဦးေဖသနး (B.Sc. Engg: Electrical) ၊ "လပစစပညာ၊ သေဘာတရား ႏင လကေတြ႕", 1992.3. Singapore CP5: "Code of Practice for Wiring of Electrical Equipment of Buildings", 2005.4. Teo C Y, "Principles and Design of Low Voltage Systems", 2nd Edition, Byte Power Publications Singapore,

1999.5. "Electricity Supply Application Handbook", TNB Malaysia6. "Application for Electricity Supply Handbook", Singapore Power

IP Ratingသသငတ ေနာကတစခ ကေတာ IP Codes of Ingress Protection (BS EN 60947–1: 1998) ပါ။ေျပာေလေျပာထ ရတာကေတာ IP ဘယေလာကလ ဆတ အခကပါ။ ဖနဒါဏ၊ ေရဒါဏ၊ ရာသဥတ ဒါဏ ဘယေလာက ခႏငလ ဆတာက ရညညႊနးတ Code ပါ။ သ႔မာ ဂဏနး ႏစလး ပါၿပး ပထမ အမႈက န႔ Dust ေတြ ကေန ကာကြယႏငမႈ ျဖစၿပး ဒတယ ကေတာ ေရအဝင ကာကြယမႈ အညႊနးပါ။

Singapore Standard Code of Practices for Electrical EngineersSingapore ႏငင သး Code of Practice ေတြ က ေရာငးခေပးေနတ Website ကေအာကမာ ေပးထားပါတယ။ http://www.singaporestandardseshop.sg (Singapore Standard e-Shop)ကယပင ဝယသးဘ႔ ကေတာ ေစးအေတာ ႀကးပါတယ။ (တစမကႏာ တစေဒၚလာ ေကာခန႔)။ ကယ ရးက Library ကပ ျဖစျဖစနးစပခငမင ရငးႏးရာ က ပျဖစျဖစ ရယ မျငမး ႏငပါတယ။ Electrical Engineer ေတြ အတြက အသးတ မ Code of Practicesေတြ က ေအာကမာ ေဖာျပထားပါတယ။CP 5 န႔ HT Distribution Network ေတြ အေၾကာငး ပ႔ခတ Training ေတြ ရပါတယ။ BCA ရ BCA Corenet မာ Subscribeလပထားရင ဒ Training Information အပါအဝင Circulars ေတြ က email န႔ ပ႔ေပး ပါလမမယ။

1. Power & LightingCP 5 : 1998 "Code of practice for electrical installations"AMD CP 5 : 2008 "Amendment No. 1 to CP 5 - Code of practice for electrical installations"CP 16 : 1991 "Code of practice for earthing"CP 18 : 1992 "Code of practice for earthworks"CP 19 : 2000 "Code of practice for the installation and maintenance of emergency lighting and powersupply systems in buildings"CP 38 : 1999 "Code of practice for artificial lighting in buildings"CP 47 : 1989 "Code of practice for temporary electrical installations for shipbuilding and shiprepairingyards"CP 87 : 2001 "Code of practice for illumination in industrial premises"CP 88 - 1 : 2001 "Code of practice for temporary electrical installations - Construction and buildingsites"CP 88 - 2 : 2001 "Code of practice for temporary electrical installations - Festive lighting, trade-fairs,mini-fairs and exhibition sites"CP 88 - 3 : 2004 "Code of practice for temporary electrical installations - Shipbuilding and ship-repairing yards"Vertical Transportation SystemsCP 2 : 2000 "Code of practice for installation, operation and maintenance of electric passenger andgoods lifts"CP 15 : 2004 "Code of practice for installation, operation and maintenance of escalators andpassenger conveyors"

http://www.corenet.gov.sg/einfo/

http://www.cumminspower.com/en/

http://www.tnb.com.my/cms/uploadfile/Highlight/ESAH.pdf

http://www.taisin.com.sg/

http://www.meidensha.co.jp/epages/prod/prod-11.html

http://www.henikwon.com/

http://www.singaporestandardseshop.sg/Search/Search.aspx?prefix=CP

http://en.wikipedia.org/wiki/IP_Code

http://www.meidensg.com.sg/index.htm

2. Fire Alarm SystemCP 10 : 2005 "Code of practice for the installation and servicing of electrical fire alarm systems"

3. Public Address SystemCP 25 : 1999 "Code of practice for emergency voice communication system in buildings"

4. Lightning ProtectionCP 33 : 1996 "Code of practice for lightning protection"

5. MATVCP 39 : 1994 "Code of practice for the installation of master antennae television systems for thereception of VHF and UHF sound and television broadcasting transmission operating between 5 MHzand 824 MHz"

Checklist for Electrical Power Systems1. Normal power source

* Utility or on-site power (capacity, phase, and voltage)* service entrance* substations* vaults, etc.

2. Emergency power source* Separate service,* on-site generation, etc.

3. Power distribution* Primary or secondary voltages* panels and substation locations

4. On-floor distribution* Under floor ducts* cellular floors,* raised floors,* ceiling conduit network,* poke-thru, etc.

5. Emergency power distribution* Critical equipment load,* emergency lighting. etc.* Critical building loads* power source (batteries. UPS, etc.)* Critical building loads, power source (batteries. UPS, etc.)

6. Power for building equipment* Mechanical* food services* process* Vertical Transportation (Elevator, escalators), etc.

Posted by Ko Chaw - ကေခာ at 10:20 PM

Labels: Electrical

1 COMMENT:

Anonymous said...

Hi Ko Chaw,

http://www.blogger.com/email-post.g?blogID=4321275198138785707&postID=3331871854888035897

http://chawlwin.blogspot.com/search/label/Electrical


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Construction Industry မာ ဆယစႏစ တစခေကာ အတြငး ရ႐ခ တ အေတြ႕အႀက အခ႔ န႔ လက႐ နညးပညာ အေျခခ ေတြ က မးဆကသစေတြ ဆ လကဆငကမးေပး ႏငဘ႔ န႔ မတဆကေပး ႏငဘ႔ အတြက ပ ရည႐ြယပါတယ။ Blog မာ အခကအလက ေတြ က အတတႏငဆး တကေအာင ေဖာျပထား ေပမ အမားေတြ ပါႏငပါတယ။ အသးခ ႏငဘ႔ကေတာ ကယတင ေလလာ၊ ဆနးစစ ေသေသခာခာ နားလညၿပး တာဝနယႏငမ လပပါ လ႔ တကတြနး လပါတယ။ အမားေတြ႔ရင လညး ျပငဆငခြင႔ ရေအာင [email protected] က အသေပးပါ။ ေကးဇးတငပါတယ။

Just to share you Janitza power monitoring devices (from Germany).

These power monitoring devices would be ideal and value-add to your control and automation solutions. It

also provides power quality solutions such as dynamic PFC and harmonics mitigating solutions, which are

widely used in industrial and commercial applications.

In summary, the power monitoring devices can be differentiated as follows.

UMG 96L – Digital power meter (Basic monitoring)

UMG 96S – Digital power meter with RS485 (Modbus RTU) …………….. Equivalent to Schneider PM710

UMG 503 – Power Analyzer with RS485 (Modbus RTU)

UMG 505 – Power Analyzer with LON networks

UMG 507 – Power Analyzer with TCP/IP (Ethernet), built-in with webserver offering remote monitoring

access, data- logging, etc

UMG 510 – Power Quality Analzyer

UMG 604 – Power Analyzer with TCP/IP, BACNET protocol.

For more details, you can visit our product URL below.

http://www.munhean.com/SG/productportfolio/category.asp?caid=236

Or you can call " +65 908 77 306" for further discussion.

Thank you.

Wit Yi

April 19, 2009 at 6:01 PM

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mailto:[email protected]

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