Can shelly uni be used as a switch like shelly 1?

    I want to use a shelly uni to do two things :

    1) Sense the buzzer has been pressed on my intercom.

    2) Act as a switch to connect two 9v dc wires to open the door

    It seems the sensing function can be achieved by connecting the two wires to Shelly uni pins 3 and 6.

    However I am not sure if the Uni can act as a switch to close a contact between two wires.

    Could anyone enlighten me if this is possible and if so what would the wiring be for the two wires to be connected?

    Many thanks

    Hi, yeah. You can use each of the two outputs for that; in the Shelly Uni the ESP8266 Wi-Fi chip controls two TLP172GM photorelays that can be open and closed, "shorting" both leads and closing any circuit you attach it to.

    Check out this thread for some diagrams and ideas, should be more or less the same: Retrofiting a 5-wire (4+N) 12 VAC analog intercom/entryphone with a Shelly UNI. Tegui Horizon N. Tasmota. Diagram and help.


    The only thing you need to keep in mind is the type of load these outputs support, the current going through it can't surpass 100 milliamps, which is enough for smaller signals but not for activating something big and mechanical like some AC electric door strike. So it may not do anything, not getting enough current through. To do that you will need to use one of the Shelly Uni outputs to control a mechanical or solid-state relay, acting like a middleman between the two.

    This page is interesting: https://toshiba.semicon-storage.com/us/semiconduct…photorelay.html

    There are small preassembled relay board kits out there, but check out the supported input voltage of the relay. Some of them only work at 12v AC, and keep in mind that SSRs are usually chunky and you can use them as-is, but they can generally only switch either AC or DC load, not both.

    Mechanical ones don't care, but you can hear them click.

    In some cases, if you have something like a regulated v12 DC power line to feed your project you might save time by using a different all-in-one ESP board with an included relay. They might be chunkier than a Shelly Uni + some SSR tucked into some wall hole, though.

    And it won't have the Shelly firmware, which is user friendly and lets you install alternative firmwares like Tasmota over the air, from your computer.

    Zitat

    Hi, yeah. You can use each of the two outputs for that; in the Shelly Uni the ESP8266 Wi-Fi chip controls two TLP172GM photorelays that can be open and closed, "shorting" both leads and closing any circuit you attach it to.

    Thanks so much. I checked and the current required is 14mv. I connected it up as you said and it works perfectly.

    One question though. When I press the door open button (on the intercom itself) just for a second the door unlocks a stays open for 20 seconds. The button is spring loaded so turns off immediately as you lift your finger.

    When I tap the button on the Shelly app it stays on (the circuit is switched on) until I turn it off. Is there a way for it to turn off automatically after say 1-2 seconds? Or only staying active while being pressed?

    I tried setting the button to “momentary” but the button still stays on after taking your finger off it.