The following speed PWM type DC motor speed controllers are suited towards Brushed DC Motors (Permanent Magnet types). These controllers will not work with a brushless motor, which uses a completely different control method!

The purpose of a speed controller is to take a signal from an input device (Potentiometer, Hall Effect Throttle, etc) and to drive a motor at that speed.

Most controllers don't measure the speed, but if they do, it's labeled as a feedback speed controller or closed loop controller or even a constant speed controller, but if not, then it is classed as an open loop controller. Feedback speed control is better, but generally more complicated.

Speed controllers work by varying the average power supplied to the motor. This means they switch one of the motors DC power lines (either positive or negative) on and off very quickly (PWM Pulse Width Modulation). If the switching is fast enough, the motor doesn't notice the on off switching at all, it only notices the average effect.

Most Speed controllers work in the low frequency range, which is generally between 300Hz to 5Khz while more advanced models can reach ultrasonic switching speeds of 32Khz.
 

Here you'll find a varied assortment of controllers, including 12-24V DC constant speed control, 12-48V PWM Controller with hall effect throttle or Potentiometer control, High frequency Bi-Directional (Reversible) speed controllers with more being developed.
We do try and cater for as many people as we can, however it takes time for designs to be finalised and tested!