The UPS trainer is a very versatile training system, has been designed to explain a very interesting and frequently used switching based power supply - The UPS (Uninterrupted Power Supply). The product is designed keeping in mind that a student can understand each block of UPS in a very easy way. Various test points have been provided so that one can check inputs and outputs of each block contained. Being different from a conventional block diagram internal structure of blocks is also shown. AVR (Automatic Voltage Regulator) is presented in such a way that a student can readily understand its functioning and pin configuration. Since UPS is different from an inverter because its switching changeover time is less than 3 mS which is very less so a computer system doesn't get reboot. Technical Specifications Input : 190 to 260 V 10%, 50 Hz Output : 230 V Transformer specifications Input : 12 - 0 - 12 V Outputs : 0, 190, 220, 240, 260 V 18 - 0 for battery charging