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


您可能感興趣的試卷

你可能感興趣的試題

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

最新試題

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

題型:單項(xiàng)選擇題

Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the()

題型:單項(xiàng)選擇題

During the diesel engine running, the water level of F.W expansion tank should normally kept in the () level of glass tube.

題型:單項(xiàng)選擇題

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

題型:單項(xiàng)選擇題

When does auxiliary burner of incinerator put into operation? ()Ⅰ. start incinerator when it is coldⅡ. the sludge for dealing with is littleⅢ. the sludge for dealing with is largeⅣ. the water and impurity in sludge are too muchⅤ. the temperature in incinerator is lowⅥ. dealing with little solid rubbish

題型:單項(xiàng)選擇題

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

題型:單項(xiàng)選擇題

Flame failure in an automatically fired auxiliary boiler can from a/an ()

題型:單項(xiàng)選擇題

By comparing the exhaust gas temperature of each cylinder, the operator can determine if the load is balanced throughout the engine. The device most commonly used is a()

題型:單項(xiàng)選擇題

To proceed to the assistance of a ship in distress is()

題型:單項(xiàng)選擇題

The Port State Control officer may witness a fire drill carried out by the crew assigned to these duties on the()

題型:單項(xiàng)選擇題