Ready now: the new, Programmable version of this controller, the Prog-150
Building on the success of 4QD's 'NCC' series is the Pro 120. It has all the features of our well tried and tested NCC series but includes a reverse polarity protection relay. The connections are all arranged at one end of the board for ease of access once the controller is boxed. The NCC-Pro-120 is a full feature Four Quadrant (acceleration and regenerative braking, forward and reverse) motor speed controller principally for 12v and 24v battery operation, but 36v and 48v versions are available. Although it is similar in size to other industry standard 110 amp controllers, the power performance is considerably enhanced with no loss of reliability.
Some possible applications are:- invalid 'scooters', golf buggies, miniature railways, kiddiecars, floor cleaners, caravan shifters and vehicle loaders. The controller is adequate for all common golf buggies but for heavier and more demanding applications such as heavy golf buggies which use two motors, two controllers can be coupled so the two motors work as one, but with independent current limiting, giving control of currents up to 240 amps. This feature is also popular with miniature railways where two engines are 'double headed'.
Available in 12v, 24v, 36v and 48v versions.
The Pro-120 is as technically advanced as is possible with an analogue controller. The controllers have been extensively 'value engineered' to give the best possible ratio of performance to cost. Of special interest is the automatic ramp down and power off so the controller always stops smoothly and safely even if the ignition is turned off at full speed. Also of interest are the independent, linear, adjustable acceleration and deceleration ramps, the 'dual ramp' automatic reversing, the thermally sensitive overcurrent limiting, the regen current limit, pot fault detection, ramp down at power off, high pedal lockout,ignition switch lockout and automatic reverse speed reduction.
Where a state-of-the-art, boxed digital controller is required, we also offer the Omega I.
| Supply voltage | 12v or 24v or 36v or 48v - depends on model | |
| Supply current | 30mA (At zero speed) | |
| Output voltage (forward) | 0 to 100% full speed, adjustable. | |
| Output current max (typ) | 155 amps (120 amps regen) | |
| 1 minute rating | 115 amps - without additional heatsink! | |
| 2 minute rating | 60 amps - without additional heatsink! | |
| continuous | 30 amps or more: ambient temp dependant | |
| voltage drop at 20a | 90mV | |
| Overheat current | 25 amps - typical | |
| Overheat temperature | 95°C - on heatsink | |
| Switching frequency | 20kHz approximately | |
| Reverse threshold | 5v approx | |
| Acceleration time | 330mSec to 7 Sec (adjustable) | |
| Deceleration time | 30mSec to 7 Sec (adjustable) | |
| Input | 5k to 25k pot or 0-3v (adjustable) into 100K nominal. | |
| Pot fault detect | greater than 30K | |
| Size | 160mm x 102mm x 40mm | |
| Weight | 325g | |

Above is a view of cased version of controller.
Additional drawings of controller, uncased and showing mounting arrangement.
There are several wiring diagrams available:
Input is suitable for a standard 10K 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.
The circuit has fully automatic regenerative braking where most of the braking energy is returned to the battery, giving greatly extended use between recharges. With a regenerative brake the motor acts as a generator during braking. At zero speed the motor isn't moving, so actual braking effect is zero, until the motor starts to turn. Regenerative braking can't therefore always replace a mechanical brake since it doesn't work well at slow speed. The circuit therefore optionally includes a driver for an electromagnetic parking brake.
You can buy with confidence as the controllers come with a detailed instruction manual and 4QD give full technical service and advice, offer a fixed price repair (when not covered by the 12 month guarantee) on return to the factory.
The Mark 2 controller will be suplied.
| Item | Price List | Add to cart |
|---|---|---|
| Pro-120-12 - board only | Add | |
| Pro-120-24 - board only | Add | |
| Pro-120-36 - board only | Add | |
| Pro-120-48/BC with Base and cover | Add |
| Item | Order code | Price List | Add to cart |
|---|---|---|---|
| Pro Base Plate | PRO-BAS | Add | |
| Cover for Pro | PRO-COV | Add | |
| Expansion connector for Double Heading, with new controller | XCP-009D | Add | |
| Expansion connector for Tacho, with new controller | XCP-009T | Add | |
| Pro Tacho Board | TFB-120 | Add | |
| Power leads (tails), 50cm | T05-069 | Add | |
| 10K potentiometer | POT-103 | Add |
You can download the instruction manual, in PDF format, via our manuals and catalogues page.