Uninterrupted power supply is mainly use for short time. Means according to ups VA it gives backup. Ups is also two types: on line
and offline. Online ups having high volt and amp for long time backup with high dc voltage. But ups start with 12v dc with 7 amps. but inverter
is start with 12v,24,dc to 36v dc and 120amp to 180amp battery with long time backup