Protection bay C2 (A804,A805,A806)
Distance protection
1.Fault current enter side should be CT P1
2.If 1 1/2 scheme CT's cover both breakers and connect the CT wires parallal and given to Relay.
3. Voltage is taken from line side VT only.
4.Give trip to 94 Electric Lock Out Relay and send the trip camand( DTTR) to other end through PSE.
5. 94 will Trip TC1 and TC2 of A805,A806 breackers and initiate BF.
6. 94 trip by the following commands.
a. 21 relay
b. 67 relay
c. DTTR from next end
d.PD trip from other end
No cammands BF from other end
9.Trip cammand send to othere end.
a. DTTR (21 relay)
b.Second stage PD trip from both breakers
a. DTTR (21 relay)
b.Second stage PD trip from both breakers
c.Secound stage Breaker failure trip from both breakers.
Breaker failure Protection
CT connection
The CT on bus side and P1 should be power intering in to breaker
A806
BF initiations
1.Set-1,Set-2, 94 LOR Al-Fadhili
2.86BB-1,86 BB -2 A806
3.86 BF (A805,A809,A812)
94 LOR (stage-1)
After 62BF-1 time
1. Retrip A806 (TC-1,TC-2)
86 BF-1, 86 BF-2 Stage-2 (2 Units)
After 62BF-2 time
1. Trip- A805
2. Bus bar intiate bus-2 (A803,A806,A809,A812)
3.Trip send Other end Al Fadili
4.Close black for A 805,A809,A812
Breaker Failure for A805
Initiation
1.86-1, 2, 3, 4 (Transformer High Side)
2.86BF A609 (Transformer Low Side)
3.86BF A804,86BF A806
4.94-1,94-2 (line-1)
94 BF Stage-1
1. After 62BF-1 time Retrip A805
86 BF Stage-2 (2 Units)
After 62BF-2
2. Trip & Close black A804,A806
3. Trip & Close black A609 & A301
4. Trip & Close black other end Al fadhili through PSE
5. BF initiation A804,A806,A609
6. Trip save A805.
Breaker Failure for A804
Initiation
1.86-1, 2, 3, 4 (Transformer High Side)
2.86BF A609 (Transformer Low Side)
3.86BF A805,86BF A807, 86BF A810
4.86 BB-1,2 A804
94 BF Stage-1
7. After 62BF-1 time Retrip A804
86 BF Stage-2 (2 Units)
After 62BF-2
8. Trip & Close black A807,A810,A805
9. Trip & Close black A609 & A301
10. Bus -1 BB initiation (A807,A810)
11. BF initiation A807,A810,A805, A609
12. Trip save A804.
Initiation
1.86-1, 2, 3, 4 (Transformer High Side)
2.86BF A609 (Transformer Low Side)
3.86BF A804,86BF A806
4.94-1,94-2 (line-1)
94 BF Stage-1
1. After 62BF-1 time Retrip A805
86 BF Stage-2 (2 Units)
After 62BF-2
2. Trip & Close black A804,A806
3. Trip & Close black A609 & A301
4. Trip & Close black other end Al fadhili through PSE
5. BF initiation A804,A806,A609
6. Trip save A805.
Breaker Failure for A804
Initiation
1.86-1, 2, 3, 4 (Transformer High Side)
2.86BF A609 (Transformer Low Side)
3.86BF A805,86BF A807, 86BF A810
4.86 BB-1,2 A804
94 BF Stage-1
7. After 62BF-1 time Retrip A804
86 BF Stage-2 (2 Units)
After 62BF-2
8. Trip & Close black A807,A810,A805
9. Trip & Close black A609 & A301
10. Bus -1 BB initiation (A807,A810)
11. BF initiation A807,A810,A805, A609
12. Trip save A804.