Direct Current (DC) Motor

 Direct Current (DC) Motor 

Another commonly used motor in industrial applications is the direct current motor. It is often used in applications where adjustable speed control is required.

Permanent magnet DC designs are generally used for motors that produce less than 5 HP. Larger horsepower applications use shunt-wound direct current motors.

DC motors can be operated from rectified alternating current of from low-voltage battery or generator source. This is a low-voltage design, which includes external connection lugs for the input power. With the rear endshield removed,as in this view, the brush assemblies and commutator that form a DC motor’s electrical heart are clearly visible.

Both designs have linear speedtorque characteristics over the entire speed range. SCR rated motors – those designed for use with common solid-state speed controls – feature high starting torque for heavy load applications and reversing capabilities, and complementary active material to compensate for the additional heating caused by the rectified AC input. Designs are also available for use on generated low-voltage DC power or remote applications requiring battery power.