Reversing DC Motors

Procedure for reversing direct current motors

Direct current motors are reversed by changing the direction of current flow through the armature or through the field. In series motors, the usual procedure is to reverse the current through the armature. Figure 1 shows this method.

All that is necessary is to interchange the leads on the brush holders. Figure 2 shows the series motor reversed by changing the current in the field circuits.

Commutating Field (Interpole) of DC Motors

Nearly all shunt and compound motors of 1/2 horsepower or more have commutating fields or interpoles located between the main poles. These interpoles have one winding of heavy wire and are connected in series with the armature as shown in figure 1. The purpose of the interpole is to prevent sparking.