This motor speed controller is suitable for AC 220/240V 50/60HZ motor. Speed regulation range is 90-1400r/min 50Hz, 90-1700r/min 60Hz. Suitable for packaging, printing, food, electronics, instrumentation, clothing industry production for speed control drive device. The controller uses high electronic circuit and integrated components for durability. It has small size, high precision, wide speed controlling range, and long service life. of use: 1. Turn off the power, connect it according to the wiring and make the connection is . 2. Fix the controller and set the speed to the lowest "0", so as to avoid sudden current and permanent damage when starting the power supply. 3. Then turn on the power and adjust the speed knob to the position. Please turn off the power when not needed. 4. The governor is connected to the motor. If the or speed is found to be inconsistent with the requirements, please adjust the fine-tuning potentiometer on the side of the product. 5. To change the running direction of the motor, simply replace the jumper lines of "CCW" and "" on the back of the controller. 6. Select and short connection, then the motor will rotate clockwise. 7. Select and CCW short connection, then the motor do counterclockwise . Colour: black Material: ABS Contents: 1 x Motor Speed Controller Only the above content, other are not included. Note: Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.