单项选择题
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
单项选择题 When you are making a high potential test on a piece of repaired electrical machinery, a rise in leakage current indicates （）.
单项选择题 The sub-multiple prefix "milli" (m) means （）.
单项选择题 A “dead front” switchboard is one （）.
