单选题When paralleling two AC generators, the frequency of the machine coming on-line, immediately prior to closing its breaker, should be （）Aslightly less than the oncoming generator frequencyBthe same as the bus frequencyCslightly greater than the bus frequencyDthe same as the bus voltage
单选题
When paralleling two AC generators, the frequency of the machine coming on-line, immediately prior to closing its breaker, should be （）
A
slightly less than the oncoming generator frequency
B
the same as the bus frequency
C
slightly greater than the bus frequency
D
the same as the bus voltage
参考解析
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