stage wise contactor是什么意思

用法例句

The selection of the design of the original three-phase five-wire dual power supply,the power switch of the total four-phase leakage protection switching,power conversion using three-level contacts,switch on power,with a total power trip switch can not supply.

原设计选用三相五线制双电源供电,总电源开关采用四级漏电保护开关,电源转换采用三级接触器,合闸送电,总电源开关跳闸,不能供电。