Closing Logic
Tripping Logic
Note:-
ABTS Block
1. Transformer Timed Over current Trip ( This trip non directional some times happend for low side fault also. So its block the ABTS)
2. Lower side BB protection Operated in Unhealthy Bus
3. Over current operate in Lower side Bus Tie
4. FFR operated in Healthy Bus
ABTS Initiation
1. Low side Incomer Manual opens
2. High side instantaneous transformer protection trip
3. Transformer Mechanical protection trip
4. High side BB protection trip
General Conditions
1. All low side breakers should be in service conditions
2. One Bus should be unhealthy condition
3. One Bus should be healthy condition
4. ABTS in service position
