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LIST OF CONTENTS
1. PLANT DETAILS
2. TESTING OBJECTIVES
3. TESTING PROPOSALS
4. SERVICES REQUIRED
5. SAFETY PRECAUTIONS
6. EMERGENCY PROCEDURES
7. STATE OF THE PLANT
8. COMMISSIONING PROCEDURE
9. COMPLETION CRITERIA
10. APPENDICES
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1. PLANT DETAILS :
THIS SYSTEM CONSISTS OF 11 KV AND 3.3 KV HT SWITCHGEARS (UNIT SWITCH
BOARD BA,BB,CA,CB FOR UNIT #1 AND UNIT #2 AND STATION SWITCH BOARD
0BA,OCA FOR 11 KV/3.3 KV STANDBY SWITCHBOARD SUPPLY IN CASE OF BOTH
GENERATORS OUT OF SERVICE)
NAME PLATE DETAILS
MAKE: BHEL,BHOPAL
RATINGS VOLTAGE : 11 KV & 3.3 KV 3PHASE 50 HZ AC
CURRENT:2750 A
11 KV SWITCHGEARS
I.The 1BA Board consists of the following HT Panels :
1. INCOMER PANEL
INCOMER FROM UT A (Unit #1)
2. PT PANELS
LINE/FEEDER PT
BUS PT
3. TIE BREAKER FROM STANDBY SWITCHBOARD(0BA)
4 . OUTGOING FEEDERS
3240 KW Cooling Water Pumps 1 & 2
2450 KW Primary Air fan A (Unit #1)
16MVA Unit Aux. Transformer A (1CAT01)
16MVA Misc. service Transformer(MST-A)
2MVA Unit service transformer A(1DAT01)
3MVA VFD transformer (ID Fan 1A Channel 1&2)
1.25MVA Bunker area service transformer(CHT-4A)
1.6 MVA ESP Service transformer (1DCT01,1DDT01, 1DET01,1DFT01).
1.25 MVA CHP transformer 1A(CHT-1A)
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0.75 MVA Track Hopper Service Transformer(CHT-2A)
1.6MVA Fuel oil service transformer (0DCT01).
7.5 MVA Station aux. Transformer. (0CAT01).
2 MVA Station Service Transformer(0DAT01)
6.3 MVA CHP Aux. TFE
5. Spare feeders
3240 KW Motor feeder
2 MVA Transformer feeder
II.The 2BA Board consists of the following HT Panels :
1. INCOMER PANEL
INCOMER FROM UT A(Unit #2)
2. PT PANELS
LINE/FEEDER PT
BUS PT
3. TIE BREAKER FROM STANDBY SWITCHBOARD(0BA)
4. OUTGOING FEEDERS
3240 KW Cooling Water Pump 4
2450 KW Primary Air fan A (Unit # 2)
16MVA Unit Aux. Transformer A (2CAT01)
16MVA Misc. service Transformer(MST-B)
2MVA Unit service transformer A(2DAT01)
3MVA VFD transformer (ID Fan 2A Channel 1&2)
1.25MVA Bunker area service transformer(CHT-4B)
1.6 MVA ESP Service transformer (2DCT01,2DDT01, 2DET01,2DFT01).
1.25 MVA CHP transformer 1B(CHT-1B)
0.75 MVA Track Hopper Service Transformer(CHT-2B)
1.6MVA Fuel oil service transformer (0DCT02).
7.5 MVA Station aux. Transformer. (0CAT02).
2 MVA Station Service Transformer(0DAT02)
6.3 MVA CHP Aux. TFE
5. Spare feeders
3240 KW Motor feeder
2 MVA Transformer feeder
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III. The 1BB Board consists of the following HT Panels :
1. INCOMER PANEL
INCOMER FROM UT B (Unit #1)
2. PT PANELS
LINE/FEEDER PT
BUS PT
3. TIE BREAKER FROM STANDBY SWITCHBOARD(0BA)
4. OUTGOING FEEDERS
10000 KW MD BFP (Unit # 1)
3240 KW Cooling Water Pump 3
2450 KW Primary Air fan B (Unit # 1)
16MVA Unit Aux. Transformer B (1CAT02)
2MVA Unit service transformer A(1DAT02)
3MVA VFD transformer (ID Fan 1B Channel 1&2)
1.6 MVA ESP Service transformer (1DCT02,1DDT02, 1DET02,1DFT02).
1 MVA Switchyard Service Transformer(0DHT01)
2 MVA Ash Sys Compressor Plant Transformer(0DDT01)
1 MVA Ash Water Power House Service Transformer(0DFT01)
2 MVA Off Side Plant Service Transformer(0DGT01)
2 MVA WTP Area Service Transformer(PT-1A)
2 MVA Station Service Transformer(0DBT01)
0.5 MVA Raw Water Pump House Service Transformer(RWT-1A)
1.6 MVA Administration Building Service Transformer(ADMT-1A)
5. Spare feeders
2450 KW Motor feeder
1 MVA Transformer feeder
IV.The 2BB Board consists of the following HT Panels :
1. INCOMER PANEL
INCOMER FROM UT B (Unit #2)
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2. PT PANELS
LINE/FEEDER PT
BUS PT
3. TIE BREAKER FROM STANDBY SWITCHBOARD(0BA)
4. OUTGOING FEEDERS
10000 KW MD BFP (Unit # 2)
3240 KW Cooling Water Pump 5
2450 KW Primary Air fan B (Unit # 2)
16MVA Unit Aux. Transformer B (2CAT02)
2MVA Unit service transformer A(2DAT02)
3MVA VFD transformer (ID Fan 2B Channel 1&2)
1.6 MVA ESP Service transformer (1DCT02,1DDT02, 1DET02,1DFT02).
1 MVA Switchyard Service Transformer(0DHT02)
2 MVA Ash Sys Compressor Plant Transformer(0DDT02)
1 MVA Ash Water Power House Service Transformer(0DFT02)
2 MVA Off Side Plant Service Transformer(0DGT02)
2 MVA WTP Area Service Transformer(PT-1B)
2 MVA Station Service Transformer(0DBT02)
0.5 MVA Raw Water Pump House Service Transformer(RWT-1B)
1.6 MVA Administration Building Service Transformer(ADMT-1B)
5. Spare feeders
2450 KW Motor feeder
1 MVA Transformer feeder
3.3 KV SWITCHGEARS
I.The 1CA board (unit #1) consists of the following
1. INCOMER PANELS
INCOMERS FROM UAT A & B(UNIT #1)
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2. PT PANELS
LINE PT – A & B
BUS PT – A & B
3. BUS COUPLER PANEL
4. BUS TRUNKING PANEL
5. OUTGOING FEEDERS
1175 KW FD Fans– A & B
900 KW CEPs– A & B
525 KW Mills – A,B,C,D,E,F,G,H,I
354 KW Boiler Circulated Water Pumps – A,B,C
355 KW DMCW Pumps – A,B,C
270 KW Insttrument Air Compressor – A & B
270 KW Plant Air Compressor
200 KW FF Spray Pump Motor
200 KW FF Hydrant Pump motor - A
6. SPARE FEEDERS
1175 KW motor feeder
900 KW motor feeder
II.The 2CA board (unit #2) consists of the following
1. INCOMER PANELS
INCOMERS FROM UAT A& B(UNIT #2)
2. PT PANELS
LINE PT – A & B
BUS PT – A & B
4. BUS COUPLER PANEL
5. BUS TRUNKING PANEL
5. OUTGOING FEEDERS
1175 KW FD Fans– A & B
900 KW CEPs– A & B
525 KW Mills – A,B,C,D,E,F,G,H,I
354 KW Boiler Circulated Water Pumps – A,B,C
355 KW DMCW Pumps – A,B,C
270 KW Insttrument Air Compressor – A
270 KW Plant Air Compressor
200 KW FF Hydrant Pump motor – A & B
6. SPARE FEEDERS
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1175 KW motor feeder
900 KW motor feeder
III.The 0CA board (unit #1) consists of the following
1. INCOMER PANELS
INCOMERS FROM SAT- A & B(UNIT #1)
2. PT PANELS
LINE PT – A & B
BUS PT – A & B
3. BUS COUPLER PANEL
4. BUS TRUNKING PANEL
5. OUTGOING FEEDERS
456 KW FA HP Water Pumps– 1,2
380 KW Transport Air Comp – 1 ,2&3
333 KW Ash Slurry Pump Motor- 1,2,3,4 (Stage – I & II)
200 KW BA Slurry Pump Motor
6. SPARE FEEDERS
456 KW Spare Motor Feeder
333 KW Spare Motor Feeder
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2.TESTING OBJECTIVE:
TO TEST THE FITNESS OF HT SWITCHGEAR PANELS AND THEIR AUXILIARIES
(MEASUREMENT,CONTROL CIRCUITS) FOR CHARGING
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3.TESTING PROPOSAL
THE FOLLOWING TESTS MUST BE CARRIED OUT IN THE PANEL
I) INSULATION RESISTANCE MEASUREMENT OF BUS
BAR(POWER,CONTROL),VCB
II) BUSBAR,CONTACT RESISTANCE MEASUREMENT
III) HIGH VOLTAGE TEST – BUS
IV) PRIMARY INJECTION TEST - VTs & CTs
V) PROTECTION, INTERLOCKS AND METERING CIRCUITS
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4.SERVICES REQUIRED
5000V INSULATION TESTER
3 PHASE 415 AC 5O Hz SYSTEM
DC CONTROL SUPPLY
HI POT AC/DC SOURCE
MEASUREMENT KIT
CURRENT INJECTION KIT
MICRO OHM METER
MILLISECONDS TIMER
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5.0 SAFETY PRECAUTIONS:
PLANT
5.1.1 Extinguisher system’s readiness
5.1.2 Load trip lever is provided
5.1.3 “11 KV/3.3 KV AC panel charged/caution” board to be fit
5.1.4 Men & materials to be kept away from switchgear panel area
5.1.5 Each test will be carefully planned so that there is no danger of mechanical or
electrical damage to the equipment under test.
PERSONNEL:
5.2.1 The Engineer-In-Charge of the testing team will inform each member of his
team as to the exact nature and extent of his contribution and
responsibilities towards the tests carried out.
5.2.2 Only nominated person will take part in the tests. All others will remain clear
Of the area.
5.2.3 All persons must acquaint themselves with the use and location of fire
extinguishers and first aid posts.
5.2.4 Adequate lighting facilities will be provided at all times.
5.2.5 Each test will be carried out under the control of the test team leader.
5.2.6 A strict and safe method of applying test leads shall be practiced. Bare wires
shall not be inserted into sockets.
5.2.7 A record of any alternation made during the test such as shorts or
disconnections, shall be made and annexed to relevant test procedures.
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5.2.8 There will be safe and easy access to all equipments under test. And test
area will be kept clean and clear of all obstructions.
5.2.9 When high voltage tests are being carried out the area will be cordoned off.
Danger/Warning Notices shall be fixed at relevant points to ensure safety.
5.2.10 Incomer shall be kept in withdrawn position.
5.2.11 The operating personnel must be kept informed of the programme of testing.
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6. EMERGENCY PROCEDURE
6.1.1 i) Transformer & control power supply should be isolated
6.1.2 ii) Emergency trip command may be given
6.3 Shock treatment chart and first aid box will be made available.
6.3 Emergency telephone numbers for Hospital and Fire Services shall be
prominently displayed.
6.4 A telephone will be available nearby.
6.5 If an abnormality is observed during charging, the TIE VCB should be
switched off immediately.
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7. STATE OF THE PLANT
7.1.1 CHECKLIST FOR THE FOLLOWING PANELS ARE CHECKED
i. INCOMER PANELS (1 & 2)
ii. OUTGOING FEEDERS
iii. BUSCOUPLER
iv. TIE BREAKER
7.1.2 ALL INCOMING AND OUTGOING CABLES TO INCOMER PANELS ARE
COMPLETED
7.1.3 INTERLOCKS FOR CLOSING AND PROTECTION FOR TRIPPING ARE TO BE
CHECKED AS PER STANDARD CHECK LIST
7.2.1 11KV Bus Duct/Cable erection from station switchgear to unit switchgear
complete in all respects.
7.2.2 The Tie Breakers at station switchgear end of tie is tested and in withdrawn
position with shutters locked.
7.2.3 All circuit breakers contained in 11KV unit switchgear in withdrawn position.
7.2.4 Clearance from Erection Department for carrying out tests on 11KV unit
switchgear and 11KV Bus duct/cable from unit to station switchgear
obtained.
7.2.5 11KV station switchgear associated with the energising of this unit switchgear
is live.
7.2.6 Safety Clearance notification issued and effective for 11KV unit switchgear
and 11KV ite bus duct/cable.
7.2.7 The associated DAS/Annunciation scheme is complete, tested and in service.
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7.2.8 The control supplies are available.
8. COMMISSIONING PROCEDURE :
8.1 Check and test all the panels of 11 KV unit switch board and associated
equipments as per their standard check list. Enter all the above details in
PICL.
8.2 Check and test the unit switchgear bus bars and the Tie bus duct/cable to the
station switchgear as per their standard check lists and enter details in PICL.
8.3 Check and test supply cables for the DC control bus and the AC heater
supplies as per their SCL and enter the details in PICL.
8.4 PRE – ENERGISING CHECKS & TESTS
i) INSPECT ANY PHYSICAL DAMAGE IN THE BUSBAR, INSULATION, PANEL
DOORS, POWER & SLIDING CONTACTS ETC. AND TO BE RECTIFIED IF
FOUND
ii) MAKING THE PANEL INSIDE DUST FREE & FREE FROM FOREIGN
MATERIALS
iii) CHECKING THE TIGHTNESS ALIGNMENT & CLEARANCE OF BUS BARS
,SMOOTHNESS IN RACKING IN & RACKING OUT OF MODULES, PROPER
MAKING OF LIMIT SWITCH CONTACTS(TEST AND SERVICE), TIGHTNESS
OF INPUT POWER CABLES AND OUTGOING POWER & CONTROL
INTERNAL WIRINGS.
iv) INSPECT ALL RELAYS AND MAKE SURE THAT ANY BLOCKING USED FOR
SHIPPING PURPOSE IS REMOVED AND THE ARMATURE MOVES
FREELY.
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v) CHECK ALL DOORS FOR PROPER MOUNTING WITH RESPECT TO THE
SWITCH HANDLE.
vi) CHECK DOOR INTERLOCK MECHANISM
vii) TEST THE PTs,CTs & RELAYS INVOLVED. KEEP THE RECOMMENDED
SETTINGS FOR THE RELAYS LIKE OVER CURRENT, UNDER VOLTAGE &
OVERLOAD PROTECTIONS, CALIBRATE THE METERS (AMMETERS,
VOLTMETERS, POWER METERS & ENERGY METERS ETC)
viii) TEST THE INSULATION OF BOARDS WITH 5000 V DC MEGGER & THE
VALUE SHOULD BE AS PER THE RELEVANT IS SPECIFICATION (MORE
THAN 50 MEGA OHMS)
ix) CHECK CLOSING & TRIPPING INTERLOCKS,OVERLOAD RELAY SETTING
OF ALL VCBs IN THE PANEL
x) MEASURE BUSBAR RESISTANCE,VCBs CONTACT RESISTANCE (SHOULD
BE LESS THAN 50 MILLI OHMS), CLOSING & TRIPPING TIME IF TEST
REPORT IS NOT AVAILABLE AT SITE.
xi) CHECK THE PROTECTION CIRCUIT WIRINGS CONNECTION BY
CONDUCTING PRIMARY INJECTION CURRENT
xii) CARRY OUT HIPOT TEST FOR 75% OF VOLTAGE MENTIONED IN THE
TEST REPORT FOR HT BUSES,100 % FOR HT INCOMING POWER
CABLES AND FIND OUT THE LEAKAGE CURRENT
xiii) CHECK THE INPUT POWER CABLE TERMINATIONS FROM
TRANSFORMER SECONDARY
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xiv) ENSURE THE PHASE SEQUENCE OF INCOMING PT WIRINGS AND
CIRCUIT CLOSING OF CTs ARE PROPER BEFORE CHARGING THE PANEL.
xv) CHECK CLOSING & TRIPPING MECHANISM OPERATES SMOOTHLY
BOTH MANUALLY AND ELECTRICALLY
xvi) SPACE HEATERS & THERMOSTAT SHALL BE IN GOOD CONDITION
8.5 Ensure all covers are provided and no conducting part is earthed.
CHARGING PROCEDURE:
8.6 Ensure tie breaker in associated station switchgear is in withdrawn position.
8.7 Ensure all feeder breakers of unit Swtichgear are in withdrawn position.
8.8 Check and record the final IR of supply cables for the DC control bus and the
AC heater supplies :
I R OF SUPPLY CABLES M Ω
FOR DC CONTROL BUS
FOR AC HEATER SUPPLIES
+ to E
- To E
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+ to E
8.9 Energise both the supply cables for DC control bus and AC heater supplies.
8.10 Put the tie breaker in Test position.
8.11 Put all control fuses for the Tie breaker in position and switch on its control
supply.
8.12 Select LOCAL/REMOTE selector switch to local and close and trip the tie
breaker once check its operation.
8.13 Check tie isolator. Interlock in closing circuit of tie breaker.
8.14 Check that tripping relays for Tie breaker and main incomer breaker are not
operated and are reset.
8.15 Select Tie breaker Local / Remote switch to REMOTE.
8.16 Give closing impulse to Tie breaker from UCB and check that the breaker
closes.
8.17 Short Terminals (tripping contact of E/F and O/C Relay) and check that
tripping relay energises and tie breaker trips.
8.18 Switch off the control supply and reset the tripping relay and remove the
shorts applied under 8.13 and 8.17.
8.19 Put the incomer breaker in Test position.
8.20 Put control fuses of Incomer breaker in position and switch on control supply.
8.21 Select Local/Remote switch of Incomer breaker to local and close and trip the
incomer breaker once to check its operation.
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8.22 Short the terminals ------------ in Incomer breaker cubicle to bypass the
“Generator Breaker closed permissive”.
8.23 Select Incomer breaker Local/Remote switch to Remote.
8.24 Give closing command by control switch in UCB and check that the breaker
closes.
8.25 Switch on the control supply to tie breaker.
8.26 Short terminals in incomer breaker and check that :
a. Incomer breaker trips
b. Tie breaker closes automatically
8.27 Reset all alarms and relays and remove shorts.
8.28 Give trip command to incomer breaker control switch in UCB to bring switch
position corresponding to breaker position.
8.29 Put check/manual switch for incomer breaker in UCB in MANUAL position.
8.30 Give closing command to incomer breaker and check that :
a. Incomer breaker closes.
b. Tie breaker trips automatically.
8.31 Reset all alarms and relays.
8.32 Give trip command to tie breaker control switch in UCB to bring switch
position corresponding to breaker position.
8.33 With incomer breaker ON and check/manual switch in manual position, give
closing command to the tie breaker and check that :
a. Tie breaker closes;
b. Incomer breaker trips.
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8.34 Reset all alarms and relays.
8.35 Trip the Tie breaker.
8.36 Switch off the control supplies to both inocmer and ite breakers.
8.37 Remove all test connections and check that any disconnections made for the
purposes of testing have been correctly reinstated in tie and incomer panels.
8.38 Keep incomer breaker in withdrawn position (It will remain in withdrawn
position till unit auxiliary transformers are commissioned).
8.39 Check ‘danger/warning notices’ are fixed at relevant points to ensure safety.
8.40 Ensure effective communications between UCB and switch board room are
established.
8.41 Check and record the final IR value of the following equipments :
a. Isolator/Tie breaker of associated station switchgear.
b. Tie breaker of Unit switchgear
c. Unit switchgear bus bar
d. Tie bus duct/cable megger used ___________ KV
IR VALUES …. M Ω
Isolator
Tie Breaker
Tie Breaker Unit Bus Bar
Tie Bus Duct /
Cable
R – YBE
Y – BRE
B – RYE
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8.42 Ensure VT is in service position with all its fuses put on.
8.43 Check all the relay settings in TIE breaker panel are as per their protection
schedule.
ENERGIZING PROCEDURE
8.44 Put the Tie breaker of associated station switchgear in service position and
close the tie breaker to charge the Tie cable.
8.45 Observe the cable for any abnormality.
8.46 Put the tie breaker in service position.
8.47 Switch on the control supply to the tie breaker.
8.48 Inform all concerned parties about the intention of charging the unit switch
board.
8.49 Put local/remote switch of tie breaker in REMOTE position.
8.50 Give closing command from the UCB to tie breaker to charge the unit switch
board.
8.51 Check and record the unit bus bar voltage for all the three phases.
8.52 Observe the unit switch board for any abnormality.
8.53 Put the synch. Check/manual selector switch to CHECK.
8.54 Check permissive contact in synchronising check relay closes.
8.55 Check the phase sequence at unit bus VT secondary terminals as detailed in
following table. (It shall be same as that of associated station board).
MEASUREMENT IN VT CUBICLE
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Voltage Measurement Phase sequence
Remarks
Phases Terminal Nos.
Volts
R - Y
Y - B
B - R
E11 - E31
E31 - E51
E51 - E11
RYB
RBY
8.56 Do the phasing out between VT secondaries of station and unit board.
8.57 Keep the board charged for 24 Hours and observe it for any abnormality.
8.58 Inspect all equipments externally for any sign of abnormality after being
charged for 24 Hrs.
8.59 It will be the duty of the testing team leader to ensure that when the system
is operating under load conditions that all equipments are externally
inspected for any sign of stress or abnormality and a copy of the results of
their inspection is attached as an appendix to this schedule.
9. COMPLETION CRITERIA
HT BUSES ARE READY FOR CHARGING. UNIT TRANSFORMERS IN CASE OF 11
KV; UATs OR SAT IN CASE OF 3.3 KV ARE CHARGED AND 11KV/3.3 KV POWER SUPPLY
MAY BE EXTENDED TO HT BUSES.
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10. APPENDICES
DRAWINGS : SLD OF ELECTRICAL SYSTEM –AUX POWER
DISTRIBUTION
KEY DIAGRAM OF 11KV SWITCHBOARDS (1BA,1BB,2BA &2BB)
KEY DIAGRAM OF 3.3 KV SWITCHBOARDS (1CA,0CA,2CA)
SCHEMATIC DIAGRAM OF 11 KV/ 3.3 KV SWITCHGEARS
LOG SHEETS : I) IR VALUES,BUS BAR RESISTANCE VALUES
OF HT SWITCHGEAR
II) TEST REPORT OF RELAYS,PTs,CTs INCLUDED IN THE
SYSTEM
III) UNDERVOLTAGE,OVERCURRENT& EARTHFAULT,
STANDBY AND RESTRICTED E/F SETTINGS
RECOMMENDED/KEPT
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I ) Insulation Resistance values of HT( KV ) Vacuum Circuit Breaker, bus
duct.
Megger details :
Rating 5KV Sl.NO. Make
Calibration Due on
Sl No Terminals
Vacuum Circuit
breaker
Busduct
1. R – E
2. Y – E
3. B – E
4. R – Y
5. Y – B
6. B – R
II) Contact(Busbar) resistance values of Circuit Breaker HT( KV)& Bus
duct.
Kelvin’s Double bridge/Micro Ohm meter details :
Sl.NO. Make
Calibration Due on
SlNo Terminals
Generator
Transformer Unit transformer
Bus duct (PH
– PH) HV
SIDE
LV SIDE HV
SIDE
LV SIDE
1. R – Y
2. Y – B