Normally-closed button - alert when contacts OPEN?

I have old-skool normally-closed magnetic sensors on 2 independently-operable garage doors. Looking for a cheap button that I can solder the wires from these sensors, and get their status into Smarthings. But buttons seem to report “presses” and “long presses” (closed contacts) rather than “releases” (open contact). As these contacts could spend days or weeks “closed”, I am hoping someone knows of a cheap button that can report a “contacts open event”. I need the wired sensors, as the wires will be run a long distance to the corner of the garage (carriage house/barn) nearest the house to get the wireless sensor signal to reach the hub. A sensor at the door side of the garage cannot reach the hub, and I don’t want to have to wire the garage for electricity to have a repeater. Thanks for any specific sensor suggestions for this admittedly oddball need.

Why not just use a Door/Window Contact Sensor with External Contacts that you can wire into your standard magnetic reed switch?


You definitely do not want to use a “Button Device” for this purpose.


The FAQ should be of interest:

FAQ: List of devices with dry contact input from external sources


Just FYI - took apart an Aqara door/window sensor, removed the reed switch, and soldered wires to run to the (ADT-Branded) garage door sensors. These sensors have 4 wires, two for normally-open contacts, and two for normally closed, so one can choose which to connect to the Aqara depending on one’s application.

Another similar hack was to take a pair of spring battery contacts (the negative contact for an AA or AAA battery) and mount them on a small hunk of plastic with wires soldered to each that run through a wall to another Aqara sensor inside. The contacts are shorted together by the deadbolt whenever my gate lock (a Kaba Simplex 900) is both closed and locked, making for a “weatherproof” sensor to go with the weatherproof lock.

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Nice, simple solutions! Thanks for the follow-up message. Always nice to hear how things turned out.