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单选题
Prior to starting an AC generator prime mover, the voltage regulator cutout switch should be placed in the （）
A
manual position
B
bus neutral position
C
raise voltage position
D
transfer position
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考题
单选题（） is provided to alternators, in the event of prime mover failure to ensure that the alternator does not act as a motor.A
Reverse current protectionB
Reverse power protectionC
Synchronising deviceD
Frequency meter
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单选题The main purpose of an electric space heater installed in a large AC generator is to （）A
prevent the windings from becoming brittleB
prevent moisture from condensing in the windings during shutdownC
prevent acidic pitting of the slip ringsD
keep the lube oil warm for quick starting
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单选题A DC generator is used to supply direct current in order to maintain an AC generator field and is known as a/an （）A
rotorB
statorC
exciterD
armature
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单选题The voltage output of an AC generator is controlled by（）A
varying the DC exciter voltageB
varying the reluctance of the air gapC
regulating the speed of the prime moverD
shorting out part of the armature windings
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单选题The instantaneous reduction in voltage of an AC generator, resulting from an increase in load, and prior to the automatic voltage regulator correcting the situation, is called voltage （）.A
droopB
dropC
dipD
regulation
考题
单选题The power factor of an AC generator operating singularly is determined by the （）A
connected loadB
prime mover speedC
field excitationD
generators rated voltage
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单选题Diesel engine cylinder head test cocks are used to（）A
check cylinder lubrication prior to starting engineB
connect exhaust gas analyzers to determine engine efficiencyC
pressure test cylinder heads to check for leaksD
remove moisture accumulations from cylinder prior to starting
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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单选题To increase the frequency of an operating AC generator, you should （）A
increase the field excitationB
decrease the field excitationC
increase the number of magnetic polesD
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单选题Mooring winches are often combined with （） units so that one prime mover drives both.A
craneB
hatch coverC
windlassD
steering gear
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单选题The star-delta starter is an effective method of （） voltage starting of a motor.A
increasedB
reducedC
unchangedD
None of the above
考题
单选题The frequency of an AC generator is adjusted by means of the （）A
main alternator field rheostatB
exciter field rheostatC
prime mover governor controlD
equalizing reactor
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单选题Reduced voltage applied to a motor during the starting period will （）.A
result in decreased acceleration time onlyB
lower the starting current and increase accelerating timeC
cause a greater starting torqueD
increase the starting current and pump capacity
考题
单选题The alternating current generator supplying a load has a voltage drop resulted from the loadWhen the load has a lagging power factor this voltage drop （）.A
is smallB
may be neglectedC
is usefulD
is considerable
考题
单选题The output voltage of a 440 volt, 60 hertz, AC generator is controlled by the （）.A
prime mover speedB
exciter output voltageC
load on the alternatorD
number of poles
考题
单选题The initial voltage of self-excitation generator set up by（）A
residual magnetismB
voltage regulatorC
electrical current for excitationD
the other running generator
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单选题Propulsion of the vast majority of contemporary merchant ships (especially containerships and VLCCs) utilizes（） as prime mover.A
gas turbineB
diesel engineC
steam engineD
gasoline engine
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单选题The overspeeding of the diesel engine driving an electric generator could cause （）.A
low voltage trip to tripB
reverse power trip to tripC
damage to windingsD
excessive exhaust temperatures
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单选题Overspeed of the diesel engine driving an electric generator could cause（）.A
low voltage tripB
reverse power tripC
damage to windingsD
excessive exhaust temperatures
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单选题On a vessel making a voyage more than 48 hours long，regulations require that（）.A
a lifeboat drill be held within 12 hours prior to departureB
fire pumps be tested by starting within 12 hours prior to departureC
the emergency generator and lighting system be tested by starting and operating within 12 hours prior to departureD
the entire steering gear be tested within 12 hours prior to departure
考题
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
考题
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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