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单选题
One factor that determines the frequency of an alternator is the（）.
A
number of turns of wire in the armature coil
B
number of magnetic poles
C
strength of the magnets used
D
output voltage
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单选题With No~1 and No~2 alternators running in parallel and the KW loads equally shared, one alternator is drawing much higher current than the other.What does this indicate?（）A
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单选题The frequency of an alternator is controlled from the main switchboard by adjusting the（）A
frequency meterB
voltage regulatorC
governor controlD
sychroscope switch
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单选题The frequency output of an operating alternator is controlled by the （）.A
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number of turns of wire in the armature coilC
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The quantity of dirt to be removed from the fuel
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the space of one holdC
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how much cargo can be stowed
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resistanceC
combinedD
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单选题An alternator switchboard has a synchroscope and synchronizing lamps, if the synchroscope is broken, which of the steps listed is the most essential before an alternator can be paralleled with the bus （）A
The breaker should be closed when one synchronizing lamp is dark and the other is brightB
The breaker should be closed when both synchronizing lamps are brightC
The frequency meter should be used to determine that the incoming alternator frequency is slightly higher than the busD
A portable phase sequence indicator must be used to verify the information from the lamps
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单选题（）is a function of the reactive / resistive characteristics of the load items and cannot be adjusted by manipulating the alternator control devices.A
Power factorB
Power ratioC
compression ratioD
Compression factor
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单选题The frequency of an alternator at a given RPM is determined by the （）.A
number of turns of wire in the armature coilB
number of magnetic polesC
strength of the magnets usedD
output voltage
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单选题The correct phase rotation of a three-phase alternator can be checked with a（）A
dynamometerB
power factor meterC
three-phase motorD
polyphase voltmeter
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