Shelly Plus 1 Wiring Problem

    Hi guys, this should be simple but I'm a complete novice with this sort of thing. I have a HTZSafe driveway alarm that connects to an intercom-type unit. On the intercom unit it has dry contact outputs for when the alarm triggers and I want to connect these to a Shelly Plus 1 but I can't get it working. I have 12v power going into 12V and L. And I've connected the outputs from the intercom to I and O. The Shelly is set for Button > Momentary > Restore Last but I get nothing when the driveway alarm is triggered. Any help appreciated.

    Welcome to the forum!

    To your issue: If I understand you correctly, you want to detect a contact closure at the intercom unit? Thus, you’ll have to connect the contact of the intercom unit to pin SW and L of the Shelly plus 1! Pins I and O are the contacts of the internal relay of Shelly…

    „Habt Geduld. Alle Dinge sind schwierig, bevor sie einfach werden!“ (aus Frankreich)

    „Nothing in life is to be feared, it is only to be understood.“ (Marie Curie, 1867-1934)

    „Es reicht nicht“, rief Schiller, „Gedankenfreiheit zu fordern, man muß auch denken können, sonst fordert man Gedankenlosigkeitsfreiheit und die ist die Freiheit zur Dummheit, welche wiederum die schlimmste Unfreiheit überhaupt ist!“
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