1 Standard industrial-grade touch knob, one touch to enter sleep state, and then touch to restart work. 2 This speed governor is used for the use of brushed DC motors, and is not suitable for speed control of brushless DC motors; nor can it be used as a voltage regulator or regulator. 3 The motor can be positive or negative. When the running direction is inconsistent with the expectation, the direction can be changed by adjusting the line sequence. 4 The input of the DC motor speed controller is direct current, so don't connect to alternating current directly, otherwise it will burn out! Do not connect the positive and negative terminals of the DC power supply in reverse, otherwise the governor may be damaged. 5 The speed control knob realizes 0%~100% adjustment. The display of "50" means that the current speed of the motor is 50% of the maximum speed of the motor. 6