Diagnostics, Audible Alarm and Efficiency: The APC-BE800 UPS has an admirable Automatic Self-test feature that ensures detection of battery fault, if any, and prompts for replacement. Its audible alarms alert on UPS power status and fluctuating voltage conditions. On return of utility power, the APC UPS system shuts down and starts up the connected electronic equipment automatically. You don't have to worry about the overload issues, as its intelligent resettable circuit breakers restores the system instantly. The APC UPS with output power capacity of 540 Watts / 800 VA has built-in energy efficient parameters that provide consistent support during frequent load shedding situations.