Given Cap bank -1 Cap bank -2 Cap bank -3 Cap bank -1 Cap Bank -2 Cap bank -3 Local Scada 1 Opened Racked out Racked out close Racked out Racked out Manual close 2 closed Racked out Racked out open Racked out Racked out Manual open 3 Racked out opened Racked out Racked out close Racked out Manual close 4 Racked out closed Racked out Racked out open Racked out Manual open 5 Racked out Racked out opened Racked out Racked out close Manual close 6 Racked out Racked out closed Racked out Racked out open Manual open Note: After tripping of CB 10 Min should be elapsed for further operation... FUNCTIONAL CHECKS OF ACCS: Mode of operation: Auto Closing and opening of capacitor Bank breaker is 5 Min In Auto Mode, the Closing of cap Bank Circuit Breakers should be in ascending order (i.e., cap bank -1, cap bank – 2, cap bank – 3 …..) Where as the opening of cap bank to be in descending order (i.e.,) cap bank -3,cap bank -2,cap bank -1 and so on. CASE 1: Bus coupler – 1(BC -1) and Bus coupler -2 (BC -2) are in open Position
Item Conditions checked by ACCS Initial position of CB Action taken by ACCS panel to issue to C.B of Remarks Control By Cap bank -1 Cap bank -2 Cap bank -3 Cap bank -1 Cap Bank -2 Cap bank -3 Local Scada 1 T -1 MVAR > 9 Opened Racked out Racked out Auto close Racked out Racked out Over MVAR 2 T -1 MVAR < 1 closed Racked out Racked out Auto open Racked out Racked out Under MVAR 3 T -2 + T -3 MVAR > 9 Racked out opened Opened Racked out Auto close Opened Over MVAR 4 T -2 + T -3 MVAR > 9 Racked out closed opened Racked out closed Auto close Over MVAR 5 T -2 + T -3 MVAR < 1 Racked out closed closed Racked out closed Auto open 6 T -2 + T -3 MVAR < 1 Racked out closed opened Racked out Auto open Auto open Under MVAR 7 T -2 + T -3 still MVAR < 1 Racked out Opened Opened Racked out Racked out Racked out Racked out CASE 3: Bus coupler – 1(BC -1) Close and Bus coupler -2 (BC -2) in open position Item Conditions checked initial position of cb Action taken by accs panel to issue to c.b of Remarks Control by
By accs Cap bank -1 Cap bank -2 Cap bank -3 Cap bank -1 Cap Bank -2 Cap Bank -3 Local Scada 1 T -1 + T -2 MVAR > 9 Opened Opened Racked out Auto close Opened Racked out Over MVAR 2 T -1 + T -2 MVAR > 9 Auto close Opened Racked out Auto close Auto close Racked out Over MVAR 3 T -1+ T -2 MVAR < 1 Racked out Closed Closed Racked out Closed Auto open 4 T -2 + T -3 MVAR < 1 Racked out Closed Auto open Racked out Auto open Auto open Under MVAR 5 T -3 MVAR > 9 Racked out Racked out Opened Racked out Racked out Auto close Over MVAR 6 T -3 MVAR < 1 Racked out Racked out Closed Racked out Racked out Auto open Under MVAR CASE 4: Bus coupler – 1(BC -1) and Bus coupler -2 (BC -2) in Close position Item initial position of cb Action taken by accs panel to issue to c.b of Remarks Control by
Conditions checked by accs Cap bank -1 Cap bank Cap bank -3 Cap bank -1 Cap Bank -2 Cap Bank -3 Local Scada 1 T -1 + T -2 +T -3 MVAR > 9 Opened Racked out Racked out Auto close Racked out Racked out Over MVAR 2 T -1 + T -2 + T -3 MVAR >1 & < 9 Closed Racked out Racked out Open Racked out Racked out Under MVAR 3 T -1+ T -2 + T -3 MVAR > 9 Racked out Opened Racked out Racked out Auto close Racked out Over MVAR 4 T -1 + T -2 + T- 3 MVAR >1 & < 9 Racked out Closed Racked out Racked out Open Racked out Under MVAR 5 T -1+ T -2 + T -3 MVAR > 9 Racked out Racked out Opened Racked out Racked out Auto close Over MVAR 6 T -1+ T -2 + T -3 MVAR >1&<9 Racked out Racked out Closed Racked out Racked out Open Under MVAR CASE 5 & 6: Under voltage and over voltage operations The Closing and opening of 33 kV capacitor bank breaker lies between 36 > 33 < 31 Item Initial position of CB Action taken by ACCS panel to issue to C.B of Remarks Control By -