PWM Speed Controller 5A (8A peak) 6-30V DC with LCD Display

This controller has now been replaced by an improved larger-sized version, please click here for more information.

This controller with integral LCD display allows you to adjust the current reaching a DC motor (or linear actuator) and hence the rotation (or extension) speed of it. You simply need to provide a DC current of between 6-30V to the lead marked 'INPUT' (ensure correct polarity here) and then attach your device to be driven to the second lead which provides the output. 

The included potentiometer control dial can be turned clockwise to increase the output or anti-clockwise to decrease it, the three-digit LCD display will show the percentage of the output current relative to the input. A green on/off push-button allows you to switch on and off the LCD and the output from the controller.

The input and output connectors are of a female DC 2.1 x 5.5mm type, two matching male screw terminal connector adapters are included with each controller (not pictured).


The controller is rated to handle a constant load of up to 5A, and 8A for short periods. A fuse or circuit breaker should be added if there is a risk of the current exceeding the rated maximum. If the input voltage falls below 6V the controller may not operate, if it exceeds 30V it will damage the controller. 

Like most DC motor controllers this device regulates the current via pulse width modulation (PWM), switching the supplied current on and off at high frequency to simulate a lower voltage. For example when the controller is set to half-speed it will be switching the output on for 50% of the time and off for the other 50% but at such a fast rate that a 12V supply would effectively read 6V at the output. Practically speaking it can be easier to think of the device as a variable voltage controller, changing the voltage that's available to the connected device.

If you want to change the direction of the output (particularly if using the controller with linear actuators) you should connect the polarity switching device at the output of the speed controller, this is because the input must be of a fixed polarity (positive to red and negative to black) for the controller to operate. 

The plastic body features a lip around the edge of the LCD and two side clips, allowing it to be panel-mounted in a rectangular slot of approximately 72 x 40mm.

See the technical details tab for a list of specifications.


Input Range: 6V - 30V DC

Output Current: up to 5A continuous, 8A peak burst (<0.5s)

Display Range: '000' - '100'

PWM Output: 0 - 100%

PWM Frequency: 16,000Hz

Controller Body Size: 80 x 43 x 27mm

Lead Lengths: 200mm each

Connectors: 2.1 x 5.5mm DC (female on leads, male on screw terminal adapters)

Weight: 95g (with connectors)

Case material: Plastic

Related Products

GLA750 12V DC Small Linear Actuator

GLA750 12V DC Small Linear Actuator

from £60.60 £72.72 inc VAT

Great value compact 12V linear actuators stocked and sold in the UK by Gimson Robotics. Up to 750N/76kg of force and low noise operation.