In the normal configuration, which bus feeds the AC ESS bus?

The AC ESS bus in the A320 is powered by AC bus 1 in the normal configuration. This is important for the operational integrity of the aircraft's electrical system, as the AC ESS bus is responsible for providing power to critical flight instruments and systems essential for safe flight.

The configuration ensures that the most important systems have a reliable power source, thereby minimizing the risk of electrical failures during flight. In the event of specific failures or disconnections, other buses and backup systems can take over, but under normal operations, AC bus 1 directly supports the AC ESS bus, maintaining the desired redundancy and safety standards. This design highlights the importance of each bus in maintaining aviation safety through effective power distribution.