Pro 120 Mark 2 build on the success of the Pro controller. This itself was a development of (and includes all the features of) the NCC series controllers. 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.

The Pro 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 Pro-120 is a full feature Four Quadrant (acceleration and regenerative braking, forward and reverse) motor speed controller principally for 12v, 24v and 36v battery operation, but a 48v version is also 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 24v and 36v versions.

The Pro is 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 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.

Specifications

Above is a view of cased version of controller. This is mounted on a Base of 4mm thick aluminium with a vacuum formed cover.

Additional drawings of controller, uncased and showing mounting arrangement.

Features

• High speed circuit
• MOSFET chopper
• Half Bridge with relays for reversing.
• Fast current limit on drive and regeneration.
• Gain adjustment
• Regen braking may be turned off (on-board adjustment).
• Electronic Ignition - separate, active. Auto-switch-off available as an option.
  There are options on the configuration of the ignition system.
• Ramps on accel and decel.
• Dual Ramp Reversing may be changed to pre-select (on-board adjustment).
• Reverse speed is half or full forward speed, selectable by on board option.
• Reverse polarity protection.
• Electromagnetic parking brake driver circuit.
• Pot fault protection (resistance).
• High Pedal Lock-out (resistance) may be turned off (on-board adjustment).
• Thermal shutdown.
• Battery discharge protection (User Option) is fitted to 24v controllers.
• Overvoltage protection.
• Dead Band reduced (compared with Mark 1 Pro) and adjustable.
• Motor shorted out at zero speed for maximum braking.
• 6 pin control connector (supplied) accepts standard miniature stranded cable (7/0.2).
• Thermal design carefully engineered to maximise output current. Long term current is limited by the relays and by general heating.
• Decelerating output option: brake output is converted to a circuit to drive braking lights which illuminate whilst decelerating.
• The integral heatsink should be bolted to an additional heatsink as required. Normally this will be the main mounting to the machine's chassis. The current limit reduces automatically if the controller gets hot, reducing the danger of failure.
• Power and motor connections are by 9.5mm tabs as standard. Two sets of 9.5 tabs are fitted for the motors. A second 6.3mm connector is fitted to the battery inputs, e.g for a charger connection. The 9.5mm tabs have a 4mm hole enabling bolted connections if required.
• Pre-crimped wires can be supplied as an optional extra.
• Optional accessory board for tacho generator closed-loop feedback servo control.
• External board available for centre-zero (joystick) control of one or two motors in 'pan & tilt' or 'sum & difference' type controls.
• Available as bare board or as cased version. Base and cover available separately.
• Expansion connector option allows tandem control of two connectors or fitting of tachogenerator control board, IR compensation board or other option. This can be factory fitted or may be customer fitted.
• Some owner changing of operating voltage is possible. See Pro Series controller, Voltages.
• Note that operating with high currents from 12v batteries is problematical. See 12v systems

Wiring Diagrams

There are several wiring diagrams available:

• A typical wiring diagram.
• With Dual channel Interface as used in Robots.
• With pushbuttons for forward and reverse.
• Wiring for a model loco with horn relay board etc.

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.

Ordering information and prices.

Controllers

Accessories

Instructions

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

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