In comparison to the two UPS’s above, the inverter of an online UPS is always running and feeding the load. The inverter supplies a sine wave output. The main electricity supply feeds the battery which keeps them charged and the inverter running. During an outage, the inverter continues running, being powered by batteries, This UPS system provides excellent regulation with the output isolated from the UPS input. This is the best option of UPS’s to provide power to critical

Unlike the 2 types of UPS above, the inverter of this UPS is always running and feeding the load. The output of the inverter is a sine wave. The utility mains feed the battery which keeps the batteries charged and the inverter running. In the event of an outage, the inverter keeps running, being powered by the batteries. The regulation of this type of UPS is excellent and the output is isolated from the UPS input. This is the ideal type of UPS to provide power to critical electronic equipment.