单项选择题

Which of the following types of motors is often designed for use in correcting power factor?（）

A.Polyphase
B.Wound-rotor
C.Induction
D.Synchronous

点击查看答案&解析

上一题目录下一题

相关考题

单项选择题

Power transformers are rated in （）.

A.kilowatts
B.ampere-turns
C.kilowatt-volts
D.kilovolt-amperes

单项选择题

The purpose of DC generator brushes is to （）.

A.neutralize armature reaction
B.conduct electric current to an outside circuit
C.convert DC current to AC current
D.provide excitation to a DC generator

单项选择题

Which of the listed precautions should be taken when cleaning the internals of a motor with compressed air?（）

A.Open the machine on both ends so as to allow the air and dust to escape
B.Be certain that the circuit breaker is opened and tagged on the feeder panel
C.Be certain that the air is clean and as dry as possible
D.All of the above