An online UPS takes the AC utility power into the input of the UPS. This AC power is rectified into DC using power electronics. This DC charges batteries and also supplies power to an inverter. The inverter turns the DC back into AC power. This inverted AC power then feeds the output loads. If the utility AC power fails at any time, the battery takes over (just like if you unplug the power from a laptop). The time that the UPS can continue to supply power is down to the size of the battery. For more information please visit http://www.calibrepower.co.uk

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