What is the difference between an online 3kVA and a line interactive 3kVA UPS?

Online UPS provide a superior output than line interactive and have an automatic bypass. Online 3kVA UPS provide a break free supply whether running on mains power or inverter power. The transfer is seamless and the load sees a continuous sinewave output. With a line interactive 3kVA UPS, the main power is conditioned by a built-in automatic voltage stabiliser. When the mains power fails or fluctuates, the inverter section provides power to the critical load from the battery supply. The transfer from and to inverter and battery power can see a small disruption in the output waveform which is covered by the capacitance inherent within a critical load’s switch mode power supply.