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單項選擇題

A signal derived from a controlled function and returned to the initiating point is called a/an （）.

A.monitoring signal
B.inverse signal
C.reverse signal
D.feedback signal

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單項選擇題

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

單項選擇題

When you are making a high potential test on a piece of repaired electrical machinery, a rise in leakage current indicates （）.

A.good insulation
B.bad insulation
C.high insulation power factor
D.a high slot discharge factor

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