Shelly 1 as a dumb switch state detector (for use with home assistant?)

  • Am I able to use Shelly 1 purely to detect the on/off state of a dumb switch? I would like to detect the on/off state of the dumb switch and trigger automations through homeassistant accordingly.

    For example, I would like to change a Yeelight bulb colour to green when the dumb switch is on, and to red when the dumb switch is off, via homeassistant. This yeelight is a completely separate table lamp which has no connection to this Shelly 1.

    I do not want Shelly directly wired to any appliance.

    Would the below work?


    My plan is to connect only:

    Live wire to L

    Neutral wire to N

    Dumb one-way switch to SW

    I and O left unconnected

    Thanks in advance!

  • No, is not an issue.



    10x Shelly 2.5 ; 20x Shelly1; 3x Shelly 1L mit Bypass und Einschaltstrombegrenzer; Shelly I3; 2 x D/W2; 2 x Shelly Plug S, 1x Shelly Dimmer und 1 Shelly H&T über Cloud, APP und Alexa gesteuert.8o8o8o

    9 x Shelly 2,5 und 4 x Shelly1 fremd verbaut, inkl. Cloud und Alexa Sprachsteuerung.

    Jeder so wie er kann!  :D :D

  • I have tried to do "this" without success and it's frustrating the hell out of me!

    I have a 120v water circulating pump that is activated by a thermostat and relay. I tested connecting L to SW on the Shelly before installing and all worked as expected.

    When the thermostat relay activates it provides 120V to the pump, so I simply took a pigtail from the relay to the SW on the shelly. The thermostat relay activates, the pump runs, the SW lead goes high, but the Shelly does not recognize it and I can't figure it out.

    Clearly the pump has a voltage drop across it, but it looks like the correct voltage on the SW on the Shelly.

    What AM I missing/being stupid about?

    (Btw - I tried with and without detached button type with the same results. I have 6 other Shellies which are working perfectly, and I'm sure it's not a Shelly issue per se, it's me!!!)