main source of electric power

• 主电源

main source of electric power的用法和样例：

例句

1. Turn on the main source switch, and the Control Unit is now put in work.
   打开主电源开关时控制部件将开始工作。
2. Three-phase UPS systems are used in most large data centers for power conditioning and battery back-up in the event of mains power failure.
   当数据中心一旦发生主电源掉电的时候，三相不间断电源系统是应用最广泛的后备电池和供电条件。