The photovoltaic relay arrived in the mail; Raspberry Pi fan Control circuit built and tested.


Software to control the fan not all straight forward.

  • Push-button software simply a change in the input pin; Easy-peasy.
  • Fan control change from an GPIO pin to a PWM servo output; Not so much.
  • Changing the indicator from a single on-board LED w/ controller to several LEDs on a unicorn display; We will see.


Push-button drivers working. Push and hold changes things between automatic and manual mode of operation. When in the manual mode, a short click will toggle the fan on and off.