4QD controllers Motor Speed Controllers
Motor controllers Accessories Shopping cart Instruction manuals Specifications and features Questions answered Service and fault finding Wiring diagrams Application notes

The 2QD is an 'old' product: it was about our simplest 2 quadrant controller, but for general use we would recommend out Uni series.

Because of its age, we regret we can no longer offer technical support on the 2QD series.

4QD's 2QD is a simple motor speed controllers for 12v, 24v, 36v and 48v battery operation. They are 'Two Quadrant', i.e. they control acceleration and braking. The controllers are state-of-the-art MOSFET chopper drivers giving fully variable fine speed control of all motors at up to 100A intermittent.

The controllers are primarily for mobile uses such as miniature railways, model cars, golf buggies and golf caddies but may be used for other applications as well. The controller is ideal for industrial purposes and is ideally suited for use as a building block where control is from a computer of similar system. Being an open circuit board with easy accessibility, they are also ideally suited to prototype and experimental work and to small quantity applications.

And as one customer said:

they're also good for custom-designed homebrew ebike experimentation by those knowledgeable enough in controllers to wish to access theirs for repairs or modifications. (since cheap off-the-shelf ones for bikes are sometimes potted as solid bricks, making them difficult or impossible to repair or modify, and none of the OTS units I've ever seen has schematics etc. available for it, unlike the 2QD, much less pages of material explaining it's entire operation!).

Specifications

• High speed circuit
• MOSFET chopper
• Half Bridge
• Fast current limit on drive and regeneration.
• Gain adjustment
• Regen braking
• Electronic Ignition - pot
• Current limit on drive and regen
• CR type ramp
• Heatsink is adequate for normal motor use (i.e. intermittent operation at maximum output). The integral heatsink may be bolted to an additional heatsink if required. The current limit reduces automatically if the controller gets hot, reducing the danger of failure.
• Power and motor connections are by 6.3mm tabs. Pre-crimped wires can be supplied as an optional extra.
• Circuit can be used to drive loads such as lamps which will work off a chopped d.c. supply.
• Optionally the controller can be supplied with regenerative braking disabled, for use where braking is undesirable.

Reversing can be done by using two controllers back-to-back to give a full four quadrant drive. Alternately use a switch or relay to change over the armature connections. For best results, 4QD also manufacture reversing controllers (4QD, Pro and NCC series).

The diagram above shows the features of the controllers, which are un-cased circuit boards. They are assembled, fully tested and guaranteed. The diagram below is a side view, showing the mounting arrangement.

Input is suitable for a standard potentiometer. There is an on-board adjustment to alter sensitivity to suit different operating mechanisms. A connector is supplied. Various speed controls can be supplied as extras, including a spring-return-to-zero speed pot arrangement suitable for hand operation.

Ordering information and prices.

The 2QD is not now beong manufactured.

Instructions

You can download the instruction manual, in PDF format, via our manuals and catalogues page.

Page Information