Meenakshi Electrical Works

Variac is the trademark name of a variable autotransformer. A variable autotransformer is a single-coil transformer in which two portions of the same coil are used as the primary and the secondary. Variable autotransformers are used for the same purposes as regular transformers, but handle lower voltages. They also differ from regular autotransformers in that they are equipped with automatic switchgear in order to automatically step a voltage up or down, depending on preset conditions.