單項(xiàng)選擇題

（） 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 protection
B.Reverse power protection
C.Synchronising device
D.Frequency meter

你可能感興趣的試題

To parallel an incoming machine to a running machine therefore it is necessary to ensure firstly that （）.

A.two frequencies must be brought into phase
B.the incoming machine accepts a small amount of load
C.the running machine must be unload
D.both voltages are equal

單項(xiàng)選擇題

The magnetic field is provided by electromagnets so arranged that adjacent poles have （）.

A.opposite polarity
B.the same polarity
C.negative polarity
D.positive polarity

无码高清视频|成人自拍视频|欧美成人午夜无码A片秀色直播|草美女视频网站|美女被操网站在线观看

（） is provided to alternators, in the event of prime mover failure to ensure that the alternator does not act as a motor.

你可能感興趣的試題

To parallel an incoming machine to a running machine therefore it is necessary to ensure firstly that （）.

The magnetic field is provided by electromagnets so arranged that adjacent poles have （）.