Uninterruptible Power supply is the first line of defense against power interruption it is sole function is to be a backup power supply for when and if power interruption becomes a reality and to ensure a continuous clean and reliable power. The uninterruptible power supply system shall be designed to supply high quality electric power to the data centre. 

The UPS consist of rectifier/battery charger, inverter, a static bypass transfer switch, an internal maintenance bypass switch and backup battery. 

The UPS shall ensure continuity of electric power to the load within the specified tolerances, without interruption upon failure or deterioration of the normal input source for a maximum protection time determined by the capacity of the back up batteries installed.