你可能感興趣的試題

Which of the following statements represents the main difference between a relay and a contactor?（）

A.Contactors control current and relays control voltage
B.A relay is series connected and a contactor is parallel connected
C.Contactors can handle heavier loads than relays
D.Contactors are made from silver and relays are made from copper

單項(xiàng)選擇題

Any electric motor can be constructed to be（）.

A.short proof
B.ground proof
C.explosion proof
D.overload proof