The NCC is now surface-mount. It has been re-christened the VTX. Apart from being built differently, the VTX is slightly shorter but operation is identical. See Vtx controllers page. Be warned therefore that if you order an NCC - you will receive a VTX.
NCC Mark 2 controllers build on the success of the NCC controller. The circuits of these are so well proven and successful that no major design was possible, but the board has been re-laid using sub-miniature resistors to give room for more features. Features that have changed are indicated in red. This page is present only for historical reference.
4QD's 'NCC' series are full feature Four Quadrant (acceleration and regenerative braking, forward and reverse) motor speed controllers for 12v, 24v and 36v battery operation. A 48v version is possible, for quantity orders only. The range is economical enough for toy cars, yet powerful enough for use in golf buggies so it provides a very cost-effective solution for virtually every application which requires a reversing motor controller in the current range up to 200 amps.
Some possible applications are:- Robots, invalid 'scooters', golf buggies, miniature railways, kiddiecars, floor cleaners, caravan shifters and vehicle loaders.
The NCC-35 is the baby of the range, covering currents up to 50 amps for short periods. For more demanding applications the NCC-70 will give currents up to 100 amps. For 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 200 amps. This feature is also popular with miniature railways where two engines are 'double headed'. All models are available in 12v or 24v versions.
The NCC series are technically advanced and packed with useful features without the 'high tech overkill' which is often used as a sales gimmick. The controllers have been extensively 'value engineered' to give the best possible ratio of performance to cost. Of special 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, reversing at zero demand speed and automatic reverse speed reduction.
The controllers are open card, for installation in your own housing.
| Supply voltage | 12v, 24v, 36v, 48v | depends on model more information. | |
| Supply current | 25mA (at zero speed) | ||
| Output voltage | 0 to 100% full speed | adjustable) | |
| Output current | NCC-35 | 55A (50 amps regen) | Limit, typical |
| NCC-70 | 110A (100 amps regen) | Limit, typical | |
| Overheat current | 20 amps typical | NCC-70, current when sensor has activated | |
| mV drop at 20 amps | NCC-70 | 120mV | typical |
| NCC-35 | 240mV | typical | |
| Switching frequency | 20kHz | approximately | |
| Size | 172mm x 81mm x 40mm | ||
| Weight | 260g | ||
| Input | 2k to 20k pot or 0-3v | adjustable | |
| Pot fault detect | greater than 25k | ||
| Acceleration time | 330mSec to 7 Sec | adjustable | |
| Deceleration time | 330mSec to 7 Sec | adjustable | |
| MST # | 0mV to 650mV | Modulation Start Threshold | |
| RAT # | 0mV to 100mV | Relay Activate Threshold | |
There are several wiring diagrams available:
The diagram shows the features of the controllers which are assembled, fully tested and guaranteed. They are varnish coated to resist humidity and moisture.
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).
NCC-35 and NCC 70-24 controllers are now sold out: VTX will be supplied instead!
You can download the instruction manual, in PDF format, via our manuals and catalogues page.