断路器和接触器应至少有一对备用触点以便向控制系统传送信号。

Breaker and contactor should have one pair of spare contacts so that signals can be sent to the control system.

youdao

断路器和接触器应至少有一对备用触点以便向控制系统传送信号。

Breaker and contactor should have one pair of spare contacts so that signals can be sent to the control system.

youdao