Variable transformers are used in a wide variety of different applications. They are the most common electrical components found in the home and in industrial settings where the amount of voltage that a load is receiving needs to be varied. Helpful in putting out differing amounts of voltage from the same input, Variable transformers are used in voltmeter, ammeters, protective relay and power supplies. The talent of the device of deriving different voltage required by the end products and maintaining the supply time to time that too from the limited available input is worth mentioning and praise worthy.