單項(xiàng)選擇題The correct phase rotation of a three-phase alternator can be checked with a()

A.dynamometer
B.power factor meter
C.three-phase motor
D.polyphase voltmeter


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1.單項(xiàng)選擇題A probable cause for a turbo generator tripping out on overspeed is a sudden()

A.loss of field excitation
B.total loss of load
C.large increase in load
D.loss of steam pressure

2.單項(xiàng)選擇題All of the following operating characteristics are listed on the name-plates of motors used aboard ship except the()

A.temperature rise
B.input kilowatts
C.horsepower
D.operating voltage

3.單項(xiàng)選擇題When would you ground an electric hand tool?()

A.When it is a DC machine
B.When it is an AC machine
C.Any machine that operates on over 100 volts
D.Only when working on wet steel plates

4.單項(xiàng)選擇題The load between two steam-driven alternators operating in parallel may be adjusted by varying ()

A.the speed of the alternators
B.the field strength of the machines
C.the power factor of the alternators
D.steam supply to the prime movers

5.單項(xiàng)選擇題The purpose of the commutator and brushes on a DC generator is to()

A.change AC to DCcurrent
B.change DC to AC current
C.neutralize a armature reaction
D.carry current to the outside circuit

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The flash point of a residual fuel oil should be used to determine the highest temperature to which oil may be heated()

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The additional mark ()in the Classification Certificate for Machinery means propulsion apparatus is remotely controlled on the navigating bridge control station, and engine assembly control station is unmanned periodically.

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One of the reasons that cause oil flowed from sludge outlet of a self-cleaning separator is()

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Diesel engine air start system check valves are opened by ()

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To shut down a diesel engine after it exceeds the set maximum speed,which type of device listed should be used?()

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The shipboard oil pollution emergency plan will be invalid after ()

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As soon as a diesel engine has started, which of the listed engine operating parameters should be checked FIRST?()

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For a given exhaust gas boiler, what is the quantity of its evaporation mainly determined?()

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