power off relay

例句：

1. 1. Please power off the relay before you start the machine.
   请在启动机器之前关闭继电器。
2. 2. The engineers had to power off the relay to fix the problem.
   工程师们不得不关闭继电器来解决问题。
3. 3.During maintenance, the power must be turned off to avoid damage to the equipment.
   维护期间必须切断电源，以免损坏设备。