High-current Motor Controllers (36-84V)(400-800A)

High efficiency controller, high continuous current, low cost,minimum overshoot, nice waveform.

Features surface mount MOSFETs on an aluminum PCB for superior heat dissipation.

IP66 rated waterproof controller by default. 



Additional information

Weight 12 lbs

Enhanced cooling performance ,get continuous current higher than 60% of peak current.

ModelNominal VoltageMax Operating VoltagePeak Current
2 Minutes
Continuous Current

General functions

  • Extended fault detection and protection. The beep sound pattern indicates the fault sources. Customers can read the error code or message in PC software or Android App also.
  • Monitoring battery voltage. It will stop driving if the battery voltage is too high and it will progressively cut back motor drive power as battery voltage drops until it cuts out altogether at the preset “Low Battery Voltage” setting.
  • Built-in current loop and over current protection.
  • Configurable motor temperature protection range.
  • Current cutback at low temperature and high temperature to protect battery and controller. The current begins to ramp down at 90℃ case temperature, shutting down at 100℃.
  • The controller keeps monitoring battery recharging voltage during regenerative braking, progressively cutting back current as battery voltage rises then cutting off regen altogether when voltage goes too high.
  • Maximum reverse speed and forward speed can be configured between 20% and 100% respectively and separately.
  • A 4pin connector to RS232 converter and USB to RS232 cable allows for configuration,programming and software upgrades using tablet which should be based on Android OS. People can do the same operation and configuration on PC software by using a standard USB to RS232 cable instead.(Recommend using USB to RS232 cable from Kelly directly)
  • Provision of a +5 volt and +12V output to supply various kinds of sensors, including Hall effective throttle or pedal type.
  • 3 switch inputs which are activated by connection to +12V. Default to forward switch, brake switch and reversing switch.
  • 2 analog 0-5V inputs that default to throttle input and motor temperature input.
  • Configurable motor over-temperature detection and protection with the recommended thermistor KTY84-130/150.
  • Dual Channel A/B encoder input to support the speed control.
  • The power supply of the controller is the standard battery voltage range.
  • Bidirectional anti-slip function(Optional) , Prevent the stationary vehicle moving in the opposite direction. After the function enabled, when the controller detects that the motor turns from standstill to the opposite direction, it will drive the motor to provide some braking force, making the vehicle stops or slows down. The braking force can be set as required. Mainly used on ride-on floor sweepers and floor scrubbers.



  • Intelligence with powerful microprocessor.
  • Synchronous rectification, ultra low drop and fast SVPWM and FOC to achieve very high efficiency.
  • Electronic reversing.
  • Voltage monitoring on 3 motor phases, bus, and power supply.
  • Voltage monitoring on voltage source 12V and 5V.
  • Current sense on all 3 motor phases.
  • Current control loop.
  • Hardware over current protection.
  • Hardware over voltage protection.
  • Configurable limit for motor current and battery current.
  • Low EMC.
  • Battery protection: current cutback, warning and shutdown at configurable high and low battery voltage.
  • Friendly high current terminals, and waterproof connectors for small signal.
  • Thermal protection: current cut back, warning and shutdown at high temperature.
  • Decelerating speed according to the brake rate when brake switch is active.
  • Decelerating speed according to the brake rate at reverse. Configurable reversing accelerating function.
  • Support three braking modes: release throttle braking, brake switch braking or reversing braking, neutral braking. Configurable brake time and brake release time in configuration program.Can program the regen amount in user program for different regen modes.
  • Configurable high pedal protection: the controller will not work if high throttle is detected at power on.
  • Current multiplication: Take less current from battery, output more current to motor.
  • Easy installation: 3-wire potentiometer can work.
  • KAC-N can support Broadcast type CAN Bus function. It is 250Kbps. CAN bus is not included in KAC-N controller by default. CAN bus is only an optional function for KAC-N
  • Standard PC/Laptop computer to do programming.There is one more choice for customers to program KAC-N controller.Standard Tablet with Android OS to do programming.Need a Z-TEK USB to RS232 cable for connecting the controller to APP program in Tablet.
  • User program provided. Easy to use.User program can be downloaded from our website for free.



  • Frequency of Operation: 10KHz
  • Standby Battery Current: < 0.5mA.
  • 5V Sensor Supply Current: 40mA.
  • Configurable battery voltage range, B+.
  • Max output frequency can reach up to 250Hz.
  • Standard Throttle Input: 0-5 Volts (3-wire resistive pot), 1-4 Volts (hall active throttle).
  • Full Power Operating Temperature Range: 0℃ to 70℃ (Mosfet temperature).
  • Operating Temperature Range:-40℃ to 90℃, 100℃ shutdown (Mosfet temperature).
  • Max Motor Current : Configurable.


Kelly KAC-N User Manual

Kelly KAC Configuration Program(PC Version)

Kelly KAC Configuration Program(Android Version)