A.are less expensive
B.require less maintenance
C.can be started across the line
D.offer a more effective means of controlling speed
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A.Alternators
B.Wave guides
C.Exciters
D.Amplidynes
A.quartered
B.unchanged
C.doubled
D.quadrupled
A.both generate alternating voltages
B.both rectify the voltage before delivery
C.are constructed at the same physical size for the same kilowatt rating
D.both supply three-phase power
A.increase the field excitation
B.decrease the field excitation
C.increase the number of magnetic poles
D.increase the speed of the prime mover
A.in series with the power source and load
B.in parallel with the power source and load
C.insuring correct polarity
D.using the lowest range possible to prevent instrument damage
最新試題
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（） is not installed on the main switchboar.
The Port State Control officer may witness a fire drill carried out by the crew assigned to these duties on the（）
The shipboard oil pollution emergency plan will be invalid after （）
Which of the following items don’t belong to dock repair works?（）
（）are used to digest the sewage to produce innocuous sludge in a biological sewage treatment plant.
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Which of the diesel engine components listed increase air density and helps to improve engine operating efficiency?（）