Dual Battery (Contd.) Option
DC busses powered from the battery following a loss of both generators are:
- Battery bus.
- DC standby bus.
- Hot battery bus.
- Switched hot battery bus.
The switched hot battery bus is powered whenever the battery switch is ON. The hot
battery bus is always connected to the battery. There is no switch in this circuit. The
battery must be above minimum voltage to operate units supplied by this bus. An amber
BAT DISCHARGE light comes on when excessive battery discharge is detected.
Battery Charger Transformer/Rectifier
Single Battery Option
The purpose of the battery charger is to restore and maintain the battery at full electrical
power. The battery charger is powered through AC ground service bus 2.
The battery charger provides a voltage output tailored to maximize the battery charge.
Following completion of the primary charge cycle, the battery charger reverts to a constant
voltage TR mode. In the TR mode, it powers loads connected to the hot battery bus and the
switched hot battery bus. The battery charger TR also powers the battery bus if TR3 fails.
With loss of AC transfer bus 1 or the source of power to DC bus 1, the AC and DC standby
busses are powered by the battery/battery charger.
