technical parameter: 1 Working voltage: DC5V~30V, input anti-reverse connection protection 2 Power: 150W 3 Working frequency: 1KHz~99KHz adjustable, 1KHz step, the default frequency is 20KHz, the accuracy is about 1% 4 Duty cycle: 0-1% step 5 Product size: 79mm*43mm*26mm Digital encoder knob operation Under the default interface: (the duty cycle is displayed by default) Short press - switch the motor on and off Long press - enter the setting interface Counterclockwise rotation - reduced duty cycle Clockwise rotation - increased duty cycle Under the settings interface: Short press - select the setting parameter, and the setting parameter switches between the lower limit of the duty cycle, the upper limit of the duty cycle and the operating frequency. The display form of the lower limit of duty cycle is "L" + two digits, the display form of the upper limit of duty cycle is "H" + two digits or "100", and the display form of working frequency is "F" + two digits. Long press - exit the settings interface Rotate counter-clockwise - the corresponding setting parameter decreases Rotate clockwise - the corresponding setting parameter increases STOP port on the back An external switch button or 3.3V level can be connected, the button is closed or the 3.3V level is pulled down to switch the start/stop state of the motor. Package includes: 1pcs x PWM DC 5V 12V 24V 150W Motor Speed ??Controller