... power-on function Smart RS232 communication interface Intelligent slot available Sealed lead-acid, maintenance free battery Technical ... Automatic Transferon overload and UPS failureBefore UPS Power-onDefault NO, user adjustable to YESVoltage Range80 ... versaLED IndicatorsStatusLoad level / Battery level, Battery , Utility Power, Inverter, Bypass, Overload, FaultAudible AlarmBypass, On battery ...