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Universal AC DC Motor Speed Controllers

These motors can become speedy if they operate without any load. This write-up will address the methods of universal ac dc motor speed control.

A motor that functions in either AC (alternating current) or DC (direct current) mode are a universal motor. When operated in both ways (AC and DC) the resultant speed has close similarity. They regularly run at increasing speeds if they lack load. It indicates that the speed of the motor will be low with the total weight. The motor speed will increase with a decrease in the mass. If not loaded, the engine runs at extreme speed, and it becomes hard to regulate the rate to less than 2000rpm. Variation in the momentum for the universal motor relates to the DC series motor. Due to its wounding series, this motor displays high kick start torque in addition to variation in the speed traits. With the high torque, high speeds are attained efficiently as a result of no load. You should not start this universal ac dc motor speed control if it has no weight.

RPM (revolution per minute) adjustments of this universal motor

Inventors employ different techniques to regulate speed and as well prevent the motor from operating at disastrous speed. Building the engine into a controller if one way of preventing it from running at no load. These motors are for medium duties that allow direct connection of the motor the system which it drives. There are other methods of setting the motor’s RPM, i.e., using a gear train in minimizing the exact load speed. In addition to using the training gear, these other motor speed control methods can work;

1.  Speed control through field tapping
2.  Speed control through resistance

Universal ac dc motor speed control through field tapping

Field poles become tapped at specific points to vary the motor speed through strength. Increased tapping’s from that field allows you to obtain different motor speeds. For needs of setting speed, wounding of the field poles in unique sections and diverse series of wires is necessary plus taps come from different parts. Nichrome wire being resistant gets wrapped on a single field pole and taps obtained from the wire connection.

Universal ac dc motor speed control through resistance

Electric motor speed control is through connecting a variable resistance in line with this motor. There is a motor current reduction in initial resistance placement. Sewing machine motors use this type of speed controls. The motor power circuit resistance is adjustable using a foot pedal. Food and drink mixers us these kinds of engines.


This motor can run at disastrous speed if it lacks a load. The two universal ac dc motor speed control methods are relevant in operating universal motors.

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