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Digital PWM Motor Speed Controller - 50A

Replacement: None. We're not selling this controller anymore but check out the rest of our motor controllers! This page is for reference only.

This motor controller, from Cana Kit, allows you to control the speed of a DC motor without sacrificing torque. This Pulse-Width-Modulation (PWM) DC motor controller can provide up to a maximum continuous current of 50A to your DC motor or other DC load thanks to a digital microcontroller based (PIC) design and highly efficient High-Power 202A MOSFET for cooler operation.

The controller has two modes of operation: Fixed or Variable frequency. The fixed frequency mode of operation runs the controller at 100 Hz. In the variable frequency mode of operation, the frequency is adjustable from 244 Hz to 3.125 KHz. Duty cycle is fully adjustable from 0% to 100% in both modes.

The controller also offers built-in soft-start feature that greatly reduces the mechanical stress on the motor as well as the electrodynamic stress on the attached cables and battery therefore extending the life span of the whole system. When power is connected to the circuit, the duty cycle will start from 0% and go up to the preset value in about 1 to 1.5 seconds.

A 12V DC fan is included with the motor controller for robust reliable continued operation under heavy loads. Please note that DC fan is only designed to work with a supply voltage of up to 12V DC. For higher voltage operation, the DC fan will need to be replaced accordingly.

  • Supply / Load Voltage: 9 to 30V DC (12V DC Recommended)
  • Soft-Start Feature
  • 50 Amps Maximum Continuous Current (@ 100Hz)
  • Frequency: Fixed (100Hz) or Adjustable (244 Hz to 3.125 KHz)
  • PWM Duty Cycle Range: 0% - 100%
  • High efficient design using High-Power 202A MOSFET for cool operation
  • Includes large double Spade Terminals for ease of connection
  • Includes Heatsink
  • Includes 12V DC Fan
  • Includes Knobs
  • Applications: Motor Control, HHO, DC / LED Light Dimmer, Heating Control, etc.


Looking for answers to technical questions?

We welcome your comments and suggestions below. However, if you are looking for solutions to technical questions please see our Technical Assistance page.

  • Really surprised that no one has mentioned a capacitor bank to keep the motor from vibrating at the PWM frequency... 5 x 4700uf capacitors worked well for my application, just wish I would have known I would need them ahead of project time :-)

  • can this be used with arduino? how? Please answer my question customer support, then i'll buy three.

    • Out of the box, these are meant to be standalone speed controllers, with the speed determined by a knob. However we've successfully hacked them in the past to drive the MOSFET with PWM from an Arduino. If you don't need the full 50A, we have smaller motor drivers that are more Arduino-friendly.

  • Can this be used to control DC motors via and Arduino or can you only control a motor via the attached potentiometers?

  • So as a PIC-based component, is this motor controller not compatible with Arduino? It shouldn't matter, as long as you send it the correct signals, right?

  • I'm also interested in using this with my own PWM control, rather than the Pots. Anyone done this?

    • The board uses a socketed PIC microcontroller. It should be easy to program up your own PIC chip just the way you want it. The pots seem to simply provide setting inputs to the PIC chip.

  • I have used three of these controls to drive small astronomical observatory domes and they are great. And the soft start feature is awesome!

  • hey there sparkfun humans/robots.
    you always say we should let you know about our projects in emails and stuff... but you never say where!
    I have recently built a walking chair using this speed controller. and i just thought I'd let you know.
    video here: http://vimeo.com/18339183

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