primary power supply的用法和樣例：
例句
- The integrated battery guarantees an operation independent from mains supply.
內置電池保證顯示不依賴主電源操作。 - 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.
當數據中心一旦發生主電源掉電的時候，三相不間斷電源系統是應用最廣泛的後備電池和供電條件。
