HELP - Controlling ceiling fan with Shelly 2.5?

  • Hi all. As summer is getting closer and Spain is quite hot already, I am wondering if I could make a weird ceiling fan to a smart one with a Shelly, to control it via voice. I am building a house and it would be great to know if this is something that can be done. :/

    Could you please give me a hand about this?

    Thanks so much in advance!

  • If you have (or buy) ceiling fans that are speed switched by changing a capacitor, then a shelly 2.5 could be wired to switch the capacitors. Usually if there is a pull switch it switches two different capacitors in line with one of the motor windings. The small value capacitor is slow speed, bigger one is medium and both in parallel is faster, some fans switch the power directly instead of both capacitors in parallel.

    One relay would be slow capacitor, second would be medium, both would be fast.

    Or if the capacitors are not paralleled, then you have only slow with the capacitor and full speed with direct connection.

    I have two ceiling fans like this and I plan to wire the Shelly 2.5 in place of the pull switch, inside the fan. This way I use the correct capacitor values as they are the ones supplied by the manufacturer.

    You must be careful to use the correct capacitors with this type of motor, the dangerous speed is the slow one, if it's too slow the motor can overheat. Seems backwards but it's important to use the correct capacitor values for the specific fan you have.

    From here you can see how the wiring works:

    http://wiki.diyfaq.org.uk/index.php/Fan_Speed_Controller

    It would be a nice product if there was a shelly fan controller, three speeds and a dimmer integrated in the standard space for a controller. Others have one but it doesn't have a dimmer for the light.

    I will do my own because I want to be able to reverse the fan as well.