There are two types of unregulated power supply (UPS) are given below;
- OFF line UPS (unregulated power supply):
The OFF line unregulated power supply (UPS) is also known as standby power supply (SPS).
In this the battery is charged when AC mains are ON and as soon as AC mains are OFF, battery discharges and supplies power to the load.
Therefore, the switching is involved in OFF line UPS and power will be available till the battery discharges.
It is helpful when there is good power supply.
- ON line UPS (unregulated power supply):
The ON line unregulated power supply (UPS) is also known as main auxiliary unregulated power supply (UPS).
In this the battery is continuously charged and then the battery delivers the DC power supply to the load.
Therefore, switching is not required and so spikes not generated. It isolates AC mains from PC.