单选题The purpose of a main switchboard circuit breakers reverse-power trip is to （）.Aprevent main circuit overloadBprotect the circuit breaker blowout coilCprevent alternator motorizationDprevent low voltage tripout
单选题
The purpose of a main switchboard circuit breakers reverse-power trip is to （）.
A
prevent main circuit overload
B
protect the circuit breaker blowout coil
C
prevent alternator motorization
D
prevent low voltage tripout
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