what are check points to be checked while charging switchyard?(CT,PT,BREAKER,P

what are check points to be checked while charging
switchyard?(CT,PT,BREAKER,POWER TRANSFORMER)

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what are check points to be checked while charging switchyard?(CT,PT,BREAKER,POWER TRANSFORMER)..

Answer / arun 9865576777

Transformer Commissioning Work

Preliminary Test

1. HT Switchgear End

 HT BKR IR Value

Open Condition Closed
Condition
R-RI= R-Y=
R-E=
Y-YI= Y-B=
Y-E=
B-BI= B-R=
B-E=

2. Transformer end

 TRF IR Value
Note: - Neutral earth should be open
LV line PT fuse& earth link open
15sec 60sec 600sec PI
HV-E
LV-E
HV-LV
After the above tests put back neutral earth line pt fuse&
earth link Connection properly.

3. LV Panel End

 LT BKR IR Value

Open Condition
Closed Condition
R-RI= R-Y=
R-E=
Y-YI= Y-B=
Y-E=
B-BI= B-R=
B-E=

Preliminary Checks

1. HT Switchgear End

 Check Relay Setting
 Check Tightness Of CT TB
 HT Cable Connection
 Interlock Trial
 Stability Check
 BKR Trial In Test Mode
 Check Fuse
 Check MTR Operation
 Reset The All Relay
 Check Control Supply
 Reset Max Value On Relay

2. Transformer End

 TRF Body Earth
 TRF Neutral Earth
 HT Cable Connection
 Check Tightness Of CT TB
 Check WTI,OTI (or) Door Inter Lock Trial
 Check OTI,WTI Setting
 LV Side Flexible Tightness
 Check Marshalling Box Control Supply

3. LV Panel End

 Check Relay Setting
 Check Tightness Of CT TB
 LV Side Flexible Tightness
 Check Line PT Fuse
 BKR Trial In Test Mode
 Check Control Fuse
 Check MTR Operation
 Check U/V Trip Throw Line PT
 Reset The All Relay
 Check Control Supply

Before Charging
 Line PT should be in service
 LV BKR should be open condition
After TRF Charging
 Note Down Electrical Parameter In HT Side & LT Side
 Phase Sequence In LT Side