单项选择题
Time delayed or delayed action-type fuses are designed to （）.
A.prevent grounds in branch circuits B.prevent opens in motor circuits C.permit momentary overloads without melting D.guard lighting and electronic circuits
单项选择题 Which of the following statements is true concerning all three-phase alternators?（）
单项选择题 The function of damper windings in a synchronous motor is to （）.
单项选择题 To repair a small electrical motor that has been submerged in saltwater, you should （）.
