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4QD-200/300 Overview

The 4QD-200/300 are full H-bridge heavy duty PWM controllers with serious current handling capabilities. With the optional enhanced air cooled or water cooled heatsink options these speed controllers can be operated at the upper end of the performance envelope for extended periods. The 4QD-200/300 dc motor controller has been used to drive the Robot Wars house robots, larger golf buggies and electric vehicles, and a wide range of electric boats.

These controllers have been superceded by our new fully digital and configurable Pro-160 / Pro-360 models.

The key features are:

  • 4 quadrant operation
  • Gain adjustment.
  • Adjustable acceleration and deceleration ramps.
  • Input by 1k ohm to 22k ohm potentiometer, direct voltage control, or PWM control by Pi or Arduino etc.
  • Regenerative braking [can be disabled].
  • Reversing.
  • Inhibit input for interlock with mechanical brake, deadmans handle etc.
  • Parking brake driver with current limit and anti-rollback.
  • Joystick (wig-wag) or single ended modes [selected by a movable link).
  • Forward – Off – Reverse push button operation is possible [see article in knowledge base]
  • Wide operating voltage: 48v controller can be used between 18v to 66v (subject to battery discharge protection setting).
  • Fail-safe, protected circuitry for reliable, safe operation even into a shorted output: no minimum inductance for safe operation.
  • Shut down circuitry shuts drive down safely under all likely failure modes, including internal or battery over and under voltage
  • Reversing speed threshold can be adjusted for operation on hills.
  • Brake Light Driver. Factory option, replaces parking brake (subject to minimum quantity order).
  • 3 heatsink options available, standard, finned air, or water cooled.

Also on board is an adjustable torque limit, which limits the continuous motor current, to avoid overloading smaller motors.Direction switching and drive / brake switching is entirely electronic so in a vehicle equipped with a 4QD it is quite permissible to change the direction switch whilst travelling at full forward speed. The 4QD will brake, stop and reverse under full control. There are on board ramp controls to separately adjust acceleration and deceleration rates. With maximum rates the controller is very lively! The standard 4QD series uses a large aluminium plate as the primary heatsink, this has a high heat capacity and is usually sufficient for the majority of applications. However for currents at the upper end of the envelope, or for extended operating times then fitting one of our water cooled heatsinks turns the 4QD-300 into one of the few water cooled motor controllers available for brushed electric motors.

The manual provides full instructions on setting up and operating the controller. The manual is available in PDF  format:

Adobe_PDF_file_icon_32x32   4QD-200 – Read manual

Adobe_PDF_file_icon_32x32   4QD-300 – Read manual