The Variable Autotransformers are those transformers that enables variable amount of voltage from a given input voltage. These are most common and excessively used electrical components that find its application in homes as well as in industrial units. These are controlled with the dial that enables them to be used as a lighting dimmer and several other applications in which controlling the voltage amount is required. Further, the Variable Autotransformers are utilized in areas where low voltage is required and the devices where high voltage applications are not suitable.