DC motor


Converting a DCM Motor

We recently bought a train set made by a renowned company and just couldn’t resist looking inside the locomotive. Although it did have an electronic decoder, the DCM motor was already available 35 (!) years ago. It is most likely that this motor is used due to financial constraints, because Märklin (as you probably guessed) […]



DC Fan Controller

This circuit is ideal to control the cooling fan of heat generated electronic gadgets like power amplifiers. The circuit switches on a fan if it senses a temperature above the set level. The fan automatically turns off when the temperature returns to normal. The circuit uses an NTC (Negative Temperature Coefficient) Thermister to sense heat. […]



DC Motor Speed Control Circuit

This circuit takes advantage of the voltage drop across bridge rectifier diodes to produce a 5-position variable voltage supply to a DC fan or other small DC motor. It is not as efficient as a switch-mode circuit but it has the virtues of simplicity and no switching hash. The four full-wave bridges are connected so […]


Circuit Diagram for DC Motor Control by A. Collins

A DC motor is an electric motor that runs on direct current (DC) electricity. Every DC motor has six basic parts — axle, rotor (a.k.a., armature), stator, commutator, field magnet(s), and brushes. The geometry of the brushes, commutator contacts, and rotor windings are such that when power is applied, the polarities of the energized winding […]



Permanent Magnet DC Motor Equivalent Circuit Diagram

A permanent magnet DC (PMDC) motor consists of a permanent magnet stator and armature windings in the rotor. The armature winding is supplied with a DC voltage that causes a DC current to flow in the windings. Interaction between the magnetic field produced by the armature current and that of the permanent magnet stator causes […]


DC Motor Speed Controller Theory and Circuits

A theory related on DC Motor Speed Controller includes the speed control application circuits are described in the following document. In order to take a signal representing the demanded speed, and to drive a motor at that speed, a motor speed controller is needed. What you will find in the depth of the document are […]