Answer / sarmadahmed

UPS mainly consists of 3 things, a battery, a charge controller and a DC to AC converter (inverter). The battery gets charged by utility. When utility is out, it supplies the load with the energy stored in the battery. Battery stores DC only so it has to be converted to AC before connecting to load which is done by inverter. Since the inverter works on electronics and doesn't provide pure sinusoidal waveform, UPS output has a lot of harmonics.

Answer / k.prakashchandra

It has a battery which gets charged from the mains and
caters to the load with help of inverter during supply failure.

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