... 1.Pure sine wave. 2.Automatic Voltage Regulator. 3.Short Circuit & Overload Protection. 4.LED Indicators. Inverter Model ... 48VCharge Voltage13V / 27V / 41V / 56VCharge Current20A MaxOutputAC 220VFrequency50/60HzApperant Power 500VA / 300W, 1KVA / 600W,1.5KVA / 900W, 2KVA / 1600W, ... Battery voltage·Short Circuit & Overload Protection·LED indicators to show status of Normal, Backup & Fault·Cold ...