Posts by Guzzi-Charlie

    That was my suggestion from the beginning,

    but again:

    In this case you need to connect everything to the breaker of your socket because the Shelly 2.5 does not have clean relais contacts!

    Another solution could be to use only th N from your socket circuit, but only if the N from the socket is the same as for the fan circuit. Anyhow this would be a case for a professional electrician to check out the correct connections because I don't know how the rules for installation in your country are and if this is possible. Maybe you have two-pole breakers which disconnects L und N together Then it's not possible/not allowed to mix N from two circuits.


    I'm not sure if you understand correct what Stefan explained.

    If you have two different breakers for the socket and the fan switch you cannot use a Shelly 1PM. The only possibility is to use one (for one speed only) or two Shelly 1 (to be able to switch both speeds on) because only Shelly 1 has clean relais contacts.

    1. You need to supply the Shelly 1 from your socket (L+N).
    2. Even the power supply for your switch has to come from the socket breaker.
    3. The output of the switch for speed 1 you have to connect to the SW of the first Shelly 1.
    4. The output of the switch for speed 2 you have to connect to the SW of the second Shelly 1.
    5. Then you connect the power supply for the switch (from fan breaker) to the Input (I) of both Shelly 1.
    6. The wire for speed 1 (to the fan) has to be connected to the Output (O) of the first Shelly 1
    7. The wire for speed 2 (to the fan) has to be connected to the Output (O) of the second Shelly 1.

    But you need to be aware that in this case you have no interlocking of the two speeds of your fan by using the APP or browser interface.


    yes you can use a Shelly 1PM for switching of one of the two speeds of your ventilation system. And yes you need a power supply for the Shelly L and N. You only need to check carefully with an multimeter if the socket and the switch are connected to the same phase/breaker. But don't forget 230V are very dangerous and if you are not familar with this please call an electrician to do this work for you.

    Nevertheless I would recommend you to use a Shelly 2.5. Then you could operate both fan speeds AND maybe could use the Shelly in roller mode with interlocking between the two speeds.