Okay, all you Arduino fans, now that you've mastered the basics of blinking LEDs, driving motors, and monitoring environmental sensors, you're ready for something a little more interesting, right ...

This machine uses a three-phase Dahlander motor, which has three operation modes: stop, half speed, and full speed. The motor uses a special mechanical switch to select the operating mode.

I used an LCD shield to display the current temperature and speed of the fan, but you can use the circuit without the LCD display. You also need to select the transistor by the type of fan that you ...