With the earthing switch closed, insertion of the withdrawable part towards the service position must be blocked after only two clockwise turns of the crank.
如果接地开关处于合闸状态，手车向工作位置的操作必须被机械联锁锁定。
2
An ultra low insertion loss GaAs MMIC RF SPDT switch based on full-ion-implantation technology is reported.
报道了利用离子注入技术研制出一种用于手机的超低插损砷化镓单片射频单刀双掷开关。
3
The switch is characterized by simple structure, polarization-independence, low optic insertion loss and interchannel crosstalk, fast response speed, small in size and low drive voltage, etc.