Autotransformer or auto venture down transformer is an electrical transformer that has just a single winding. This one twisting goes about as both essential and optional. By the name "Autotransformer" it doesn't mean any sorts of programmed instrument. Here "auto" signifies "auto" (Greek for "self") – following up on itself.

Despite the fact that Autotransformer utilize one twisting however it utilize time-differing attractive fields to exchange control. They require substituting streams to work legitimately and won't work on coordinate current.

Activity of Autotransformer

In Autotransformer the essential voltage is connected in two end terminals and in optional there are a few tap point from which variable voltage can be accomplished.

Preferred standpoint of Autotransformer 

With less windings and a littler center Autotransformer is lighter, less expensive and littler than customary double winding transformer. Autotransformer is productive up to a voltage proportion of around 3:1; past that range, a two-winding transformer is normally more prudent.