ht swbd test schedule

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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


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)


3MVA VFD transformer (ID Fan 2A Channel 1&2)

1.25MVA Bunker area service transformer(CHT-4B)


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



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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


4. OUTGOING FEEDERS

10000 KW MD BFP (Unit # 1)


2450 KW Primary Air fan B (Unit # 1)

16MVA Unit Aux. Transformer B (1CAT02)


3MVA VFD transformer (ID Fan 1B Channel 1&2)


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



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


4. OUTGOING FEEDERS

10000 KW MD BFP (Unit # 2)


2450 KW Primary Air fan B (Unit # 2)

16MVA Unit Aux. Transformer B (2CAT02)


3MVA VFD transformer (ID Fan 2B Channel 1&2)


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



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



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



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

ht swbd test schedule

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