station Source c/o Procedure stage 1 Dadri

 

 In stage 1 we have two station transformers (ST1 and ST2). In case of planned outage or emergency tripping of one station transformer the station bus of that  station transformers can be charged via available station  transformer

 

 

 

Case 1 : Charging of  station bus SC bus via station bus SA

 

1. Open Station transformer 1 & 2 scheme in station common OWS (fig (i))
2. See which breaker among CBE 213 and CBE 217 is in closed condition. In normal condition one breaker (CBE 213 or CBE 217) must be in closed condition.
3. If CBE 213 is in closed condition  then

a)      Select Breaker CBE 216 ( SC incomer from ST#2)  in SA-SC trip selector. (fig (i))

b)      Turn the common synchronizer  switch on common electrical  vertical panel  to check mode (fig (ii))

c)      Put Synchroscope (on common electrical  vertical panel  ) in ON mode (fig (iii))

d)     Select breaker CBE 217 (SC tie from SA) and check its permissive

e)      After ensuring all the permissive are coming , close  breaker CBE 217

f)       After closing of CBE 217(SC tie from SA)  breaker CBE 216 ( SC incomer from ST#2)  will open in auto and SC bus will get charged by SA bus

 

4. If CBE 217 is in closed condition  then

a.       Select Breaker CBE 216 ( SC incomer from ST#2)  in SA-SC trip selector. (fig (i))

b.      Turn the common synchronizer  switch on common electrical  vertical panel  to check mode(fig (ii))

c.       Put Synchroscope (on common electrical  vertical panel  ) in ON mode (fig (iii))

d.      Select breaker CBE 213 (SA tie from SC) and check its permissive

e.       After ensuring all the permissive are coming , close  breaker CBE 213

f.       After closing of CBE 213 (SA tie from SC)breaker CBE 216 ( SC incomer from ST#2)  will open in auto and SC bus will get charged by SA bus

 

 

 

 

 

 

 

 

Case 2 : Charging of  station bus SD bus via station bus SB

 

1. Open Station transformer 1 & 2 scheme in station common  OWS. (fig (i))
2. See which breaker among CBE 215 and CBE 219  is in closed condition. In normal condition one breaker (CBE 215 or CBE 219) must be in closed condition.
3. If CBE 215 is in closed condition  then

a)      Select Breaker CBE 218 ( SD incomer from ST#2)  in SB-SD trip selector. (fig (i))

b)      Turn the common synchronizer  switch on common electrical  vertical panel  to check mode (fig (ii))

c)      Put Synchroscope (on common electrical  vertical panel  ) in ON mode (fig (iii))

d)     Select breaker CBE 219 (SD tie from SB) and check its permissive

e)      After ensuring all the permissive are coming , close  breaker CBE 219

f)       After closing of CBE 219(SD tie from SB)  breaker CBE 218 ( SB incomer from ST#2)  will open in auto and SD bus will get charged by SB bus

 

4.    If CBE 219 is in closed condition  then

a.       Select Breaker CBE 218 ( SC incomer from ST#2)  in SB-SD trip selector. (fig (i))

b.      Turn the common synchronizer  switch on common electrical  vertical panel  to check mode(fig (ii))

c.       Put synchroscope  (on common electrical  vertical panel  ) in ON mode (fig (iii))

d.      Select breaker CBE 215 (SB tie from SD ) and check its permissive

e.       After ensuring all the permissive are coming , close  breaker CBE 215

f.       After closing of CBE 215 (SB tie from SD)breaker CBE 218 ( SD incomer from ST#2)  will open in auto and SD bus will get charged by SB bus

 

 

Case 3 : Charging of  station bus SA bus via station bus SC

 

1. Open Station transformer 1 & 2 scheme in station common  OWS (fig (i))
2. See which breaker among CBE 213 and CBE 217 is in closed condition. In normal condition one breaker (CBE 213 or CBE 217) must be in closed condition.
3. If CBE 213 is in closed condition  then

a)      Select Breaker CBE 212 ( SA incomer from ST#1)  in SA-SC trip selector. (fig (i))

b)      Turn the common synchronizer  switch on common electrical  vertical panel  to check mode (fig (ii))

c)      Put synchroscope (on common electrical  vertical panel  ) in ON mode (fig (iii))

d)     Select breaker CBE 217 (SC tie from SA) and check its permissive

e)      After ensuring all the permissive are coming , close  breaker CBE 217

f)       After closing of CBE 217(SC tie from SA)  breaker CBE 212 ( SA incomer from ST#1)  will open in auto and SA bus will get charged by SC bus

 

      4.     If CBE 217 is in closed condition  then

a.       Select Breaker CBE 212 ( SA incomer from ST#1)  in SA-SC trip selector. (fig (i))

b.      Turn the common synchronizer  switch on common electrical  vertical panel  to check mode (fig (ii))

c.       Put Synchroscope (on common electrical  vertical panel  ) in ON mode (fig (iii))

d.      Select breaker CBE 213 (SA tie from SC) and check its permissive

e.       After ensuring all the permissive are coming , close  breaker CBE 213

f.       After closing of CBE 213 (SA tie from SC)breaker CBE 212 ( SA incomer from ST#1)  will open in auto and SA bus will get charged by SC bus

 

 

 

Case 4 : Charging of  station bus SB bus via station bus SD

 

1. Open Station transformer 1 & 2 scheme in station common  OWS. (fig (i))
2. See which breaker among CBE 215 and CBE 219  is in closed condition. In normal condition one breaker (CBE 215 or CBE 219) must be in closed condition.
3. If CBE 215 is in closed condition  then

a)      Select Breaker CBE 214 ( SB incomer from ST#1)  in SB-SD trip selector. (fig (i))

b)      Turn the common synchronizer  switch on common electrical  vertical panel  to check mode (fig (ii))

c)      Put Synchroscope (on common electrical  vertical panel  ) in ON mode (fig (iii))

d)     Select breaker CBE 219 (SD tie from SB) and check its permissive

e)      After ensuring all the permissive are coming , close  breaker CBE 219

f)       After closing of CBE 219(SD tie from SB)  breaker CBE 214 ( SB incomer from ST#1)  will open in auto and SB bus will get charged by SD bus

 

4.    If CBE 219 is in closed condition  then

a.       Select Breaker CBE 214 ( SB incomer from ST#1)  in SB-SD trip selector. (fig (i))

b.      Turn the common synchronizer  switch on common electrical  vertical panel  to check mode (fig (ii))

c.       Put synchroscope  (on common electrical  vertical panel  ) in ON mode (fig (iii))

d.      Select breaker CBE 215 (SB tie from SD ) and check its permissive

e.       After ensuring all the permissive are coming , close  breaker CBE 215

f.       After closing of CBE 215 (SB tie from SD)breaker CBE 214 ( SB incomer from ST#1)  will open in auto and SB bus will get charged by SD bus

 

Note:

After ensuring proper charging of station bus don’t forget to reset Circuit breaker using toggle switch CB reset provided in OWS and put synchronoscope in off mode and its witch in manual mode.

 

 

Prepared By:

Abhinav Chitranshu

Operation-th

Group-1