The multi speed induction motors offers two or more outputs and speeds from a single frame. In general, two speed motors are made up of either one or two windings in one stator.
They can be divided into two different winding types ;
Dahlander, pole changing or tap and wound :Comprises a single winding with two stator winding polarities which gives the ability to change motor speeds at ratios of 2:1 by varying the connections. The 4/2 and 8/4 pole motors stipulated at .Ratings and performance. pages are dahlander wound motors.
Two separate windings or dual wound :The motor has two distinctly different windings of different polarities within the same stator with each having its own power rating. This design is mostly used for those applications where the polarity ratios of pole change are inappropriate. The 6/4 and 12/4 pole motors stipulated at .Ratings and performance. pages are dual wound motors.