In my case, I used 12VDC power supply to the motor because this voltage level is compatible with L293D Motor Arduino Shield. If you want to use a 24VDC power supply, the motor control module must ...

We set the potentiometer pin as 0 (A0 on the Arduino Uno board), the CONTROL variable is the voltage that is used to cotrol the led brightness of the speed of the fan. In the setup() function the ...