240V 10A Motor Speed Controller Kit with Soft Start

via Jaycar

Refer: Silicon Chip Magazine February/March, 2014.
A significant improvement on our successful KC-5478 10A Motor Controller Kit. Designed for controlling the speed of power tools such as electric drills, lawn edgers, circular saws, routers or any other appliance with a universal (brush-type) motor, rated up to 10A. The new design is easier to build, has a smoother control, more "grunt" at low speed, features soft start to avoid dangerous kick-back, and improved overload protection. The case has the tricky cut-outs pre-machined, but a little bit of  fine tuning may be required to complete the project. Kit includes screen printed machined case, double-sided PCB, GPO, programmed micro and electronic components.


- Extremely smooth and precise motor speed control
- Speed can be controlled from zero to maximum
- Superb speed regulation under load
- Adjustable speed regulation with feedback control
- Excellent low-speed motor operation
- 2300W (10A) rating
- Cycle-by-cycle current overload protection
- Over-current limiting
- Soft starting
- NTC Thermistor for initial surge current limiting
- Fused protection
- Rugged case with interference suppression included
- For 230VAC brush (universal) motors
- Speed adjustment: Zero to motor’s maximum
- PWM frequency: 980Hz
- Cycle-by-cycle current limiting: 23A peak
- Average current limiting: 15A
- Soft start rate: Up to 2.54s from zero to full speed
- NTC thermistor: 10-ohm at 20°C, <0.1-ohm@10A

Note: Not suitable for inducted or shaded-pole motors

Assembly required
Output terminals 3 Pin AU/NZ Mains Plug / Socket
Output voltage selection Potentiometer
Kit Form Full Form (circuit and enclosure)
Kit Group General Projects
Difficulty Complex
Contains High Voltage Components
Instructions Included
Application Field Motor Speed Controller
Estimated Construction Time 4hr
Tools required Soldering Iron,Long Nose Pliers,Flat Head Screwdriver
Recommended Minimum Age 18Yr
AC Voltage rating 240V
AC current rating 10A