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单选题
Generators should have an excitation/voltage regulation system which will enable them to share the steady state reactive load （） no machine exceeds its proportional share of reactive load by more than 10% of the rated reactive load of the largest generator.
A
when
B
so as
C
such that
D
though
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更多 “单选题Generators should have an excitation/voltage regulation system which will enable them to share the steady state reactive load （） no machine exceeds its proportional share of reactive load by more than 10% of the rated reactive load of the largest generator.A whenB so asC such thatD though” 相关考题
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To cut in additional generators automatically as requiredC
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考题
单选题Generators should have an excitation/voltage regulation system which will enable them to share the steady state reactive load （） no machine exceeds its proportional share of reactive load by more than 10% of the rated reactive load of the largest generator.A
whenB
so asC
such thatD
though
考题
单选题When securing an AC generator, you should FIRST （）.A
open the generator circuit breakerB
switch the voltage regulator to “manual”C
decrease the field excitation to minimumD
reduce the load on the unit
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keep them cool when the vessel is underwayC
make them more accessible for repairsD
prevent accidental ignition of any gasoline vapors that may have accumulated in the bilges
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单选题Why is it desirable to operate paralleled AC generators at the same power factor?（）A
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Field excitation losses are kept to a minimumC
Generator rotors will have a lesser tendency to huntD
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It has current transformersC
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Its excitation system is vulnerable to voltage variations
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manual positionB
bus neutral positionC
raise voltage positionD
transfer position
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voltage regulatorC
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higher current and voltage ratingC
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low voltage batteryB
motor attenuator setC
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outboard diesel engineC
outboard gasoline engineD
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both generate alternating voltagesB
both rectify the voltage before deliveryC
are constructed at the same physical size for the same kilowatt ratingD
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means of rheostat the governor settingsB
a balance coil excitationC
adjusting the governor settingsD
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first-aid techniques for treating electrical shockC
cardiopulmonary resuscitation (CPR)D
All of the above
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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 frequencyB
the same as the bus frequencyC
slightly greater than the bus frequencyD
the same as the bus voltage
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单选题The voltage developed by an AC generator is controlled by varying the （）A
speed of the prime moverB
AC excitation to the fieldC
DC excitation to the fieldD
DC excitation of the voltage regulator
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