4QD - DC Motor Control
The 4QD-200 and 4QD-300 are full 4 quadrant motor speed controllers suitable for battery operated motors up to 300A and voltages between 24v and 60v. They give full control of forward and reverse acceleration and braking. They have been developed in conjunction with a top motor manufacturer and golf buggy manufacturers. Although small they are fully electronic and need no external relays. They have many failsafes built in for reliable long time use (and abuse).
|Supply voltage||18v to 66v (abs max)|
|Voltage drop at 100 amps |
(typical, full speed)
|Output voltage||on 24v||0v to +24v|
|on 36v||0v to +36v|
|on 48v||0v to +48v|
|Output current||max, cold||210A and 320A||typical|
|4 minute rating||150 amps||4QD-200-24 without additional heatsink.|
|hot||160A and 240A|
|Current limit adjustment||20% to 100% full current|
|Overheat cut-out||95°C internal temperature|
|Acceleration||0.3s to 12 sec, linear||adjustable|
|Deceleration||0.3s to 12 sec, linear||adjustable|
|'Ignition On' threshold||> 3v|
|'Reverse' threshold||3-6v||with link J2 open. Depends on issue|
|Switching frequency||20kHz approximately|
|Size (mm)||200||250 x 103 x 60|
|300||280 x 103 x 60|
|Weight||200||1300g||of which heatsink is 650gm|
|300||1685g||of which heatsink is 725gm|
|Input||from Pot or joystick (5K to 10K) or voltage following|
|Single-ended mode||0-2.5v (adjustable) for 0-25v out||separate forward reverse signal|
|Joystick mode||5.5v +/1 1.5v||speed and direction|
|Mode switch||Single ended or Joystick|
|Brake output||1A||overcurrent operates at about 1.2 amp|
Input is suitable for a joystick (center zero) or for a single ended speed pot plus separate reversing switch (mode is selected on board by a movable link). There is an on-board adjustment to alter input sensitivity. Alternatively an external pot or switch can be added to give a user top-speed control.
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!
Output devices are kept in their safe operating area so failures are rare. However 4QD have considered the possible failure mechanisms. Worst would be an output device failing short-circuit so the drive would go to full speed. Such failures normally cause the MOSFET gate to go short-circuit. This condition is normally detected by internal circuitry and shuts the controller off completely and safely. Control circuit failures could be over-ridden by the ignition switch.
Mechanical construction is such that the controller can be mounted in thermal contact with the vehicle chassis, so this acts as additional heatsinking, although this is not normally required.
Please consult the factory for variations to the above specification or for more information.
Photographs are being added: click on the thumbnail for the full version.
|4QD-300-48||4QD-300-48 without cover|
|Item||Price List||Add to cart|
You can download the instruction manual, in PDF format, via our manuals and catalogues page.