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You are attempting to parallel two AC generators and the synchroscope pointer is revolving in the slow directionThis indicates that the frequency of the incoming machine is _____.

A.higher than the bus frequency
B.lower than the bus freouencv
C.the same as the bus frequency but out of phase with it
D.the same as the bus frequency, and the circuit breaker may be closed at any pointer position

试题出自试卷《海船船员适任证书三管轮模拟试题2(轮机英语)》

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