Answer Posted / s@nz
LBB as ssaid above it means LOCAL BREAKER BACK UP RELAY is a
back up protection for local breaker (CIRCUIT BREAKER) a
predefined time set in the relay and when the circut breaker
for LBB is kept does not operate ( during fault conditions)
in the pre defined time the surrounding breakers are given
trip command by the LBB relay to restriced the fault..
| Is This Answer Correct ? | 78 Yes | 13 No |
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