Curtis launches motor speed controllers

Edited by the Engineeringtalk editorial team May 4, 2009

Curtis Instruments has introduced Models 1225/1235 programmable, microprocessor-based motor speed controllers housed in a rugged, sealed, aluminium enclosure.

They are designed for permanent magnet motors, such as those used in mobility aids, scrubbers, personnel carriers and small walkies.

Four quadrant, full bridge power output stages provide solid state motor reversing and full regenerative braking power.

They offer smooth, silent, cost-effective control of motor speed and torque.

provides extensive standard features.

provides additional features (euroeuro) for special industrial applications.

Model 1225 features: full-bridge power Mosfet design for infinitely variable forward, reverse, drive and brake control; silent high-frequency and high-efficiency operation; programming through the Curtis PMC 1311 or 1314 handheld programmer, an optional universal unit used for programming, testing and diagnostics; complete diagnostics also available through the PowerOn LED; full compliance with all applicable international standards and TUV requirements; available for wig-wag (centre-off) and single- ended (speed pot and direction switch) throttles for standard full-stroke and restricted-range 5k1 and 2 potentiometers; 0-5V throttle signal acceptance; throttle calibration mode for mechanical centring of the throttle, using the 1311 programmer to enter the mode; horn sound and status LED off, whenever the throttle is outside the neutral band; Multimode input, selecting between two operating modes - Multimode allows changes in speed, acceleration, deceleration, current limit and IR compensation, allowing optimisation of vehicle characteristics in each mode, for example indoor/outdoor; speed limit input, providing additional variable-speed limiting, in both mode ranges, with an external pot; linear acceleration and deceleration with softened response for smooth operation; current limited in both driving and regenerative braking; load compensation stabilises speed on ramps and over obstacles - compensates for battery voltage, voltage drops and motor resistance.

Model 1235 features: high pedal disable (HPD) function, monitoring status of the throttle during turn-on and preventing operation until the throttle has been returned to neutral; power-off deceleration, providing a controlled deceleration if the key switch is turned off while driving; comprehensive fault-detect function, monitoring main contactor, output stage, and throttle demand versus output; throttle fault circuitry that shuts off controller if throttle signal goes out of range; missing brake detector that forces neutral in the event of an open brake circuit (programmable); anti-rollback/roll forward circuitry, setting brake delay according to speed and direction, for improved braking response and minimised rollback on hills; over-current-protected brake driver, protecting the controller from shorts in the brake or its wiring - this low-side output driver can also be programmed for side broom or brush contactor, hourmeter and BDI-enable; brake PWM, allowing the brake driver to be programmed to a reduced holding voltage; reverse output, driving a piezo beeper (customer supplied) in reverse; Push Too Fast feature, allowing motor to coast with controller off and brake released - pushing too fast automatically and safely shorts the motor to limit maximum coasting speed; push input that electrically releases brake for key-on pushing (requires the vehicle to be stopped first); inhibit input that disables the controller and puts the vehicle in a safe state during charging; power saver that deactivates the main relay after 25s and entire controller after 25 minutes of non-operation; under-voltage cutback function, protecting against low battery voltage; thermal protection and compensation, for stable output and over-temperature protection; reverse polarity protection (battery input).