Suggestion for relay controlled by unpowered switch

Ok so I have the feeling my google fu is just failing me, but I have two use cases here for the same basic thing. Close/open a switch/microswitch and have the device report the switch position and turn the power on. I’m trying to avoid contact sensors if I can and the location of the switch is not great for motion sensor for one.

I know about the Zooz Zen16 multi-relay, but looking for something with a smaller form factor which could maybe just go in a regular junction box behind the switch?

Would something like a Sonoff ZBmini or Tuya equivalent work for you.

See this is exactly why I knew posting here would get me there. This is what I’m looking for, but its a good example of how its sometimes difficult to come up with the exact search terms or sometimes even figure out exactly what devices do what from their own descriptions. I’ve been searching for dry contact input, low voltage input, etc for a bit and this one didn’t come up.

For those that come across this thread later this device’s listing advertises “weak current for safety” on the switch terminals. A little google searching indicates the switch terminals are logic level voltage (3.3V reported) so should be same with both small switches and more importantly small wire.

Appreciate the link and I’ll order a couple and try them out. I have some fairly small gauge taperwire and with a light dusting of texture and a paint touchup this should give a basically fully hidden install without having to have a safety concern about somebody severing the wire later and without having to do a ton of sheetrock work.

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The Zooz ZEN51 might also be an option: switch input and a dry contact relay output.

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I’ve seen the zen51 but looking at the wiring diagrams they show line voltage on the switches. That’s fine for normal lighting but not for smaller switches.

There are several straight forward options if you’ve got access to 120v wiring for the switch circuit.

Ok, so on paper the Sonoff ZBMini should have been the ticket. It should work with any switch and the switch circuit is logic level voltage so even a small microswitch should be fine. According to some videos on their site it should support 3 modes for switch behavior which allow you to switch states based on the rise or fall on the logic circuit.

But in practice, the one I got came defaulted to switch on every rise and fall. So close the switch and the light goes on then open the switch and the light goes off. Great so far. Now turn the light on from the app and then close the switch. What you’d hope is that the light would stay on but what you get is a state change and the light is now off. So basically the switch default behavior is like a 3 way switch. with the device internal relay state being the other switch in the 3 way setup.

It supposed to have a follow mode where the internal logic and the switch logic are parallel so that you can turn it on from the app and then then open the switch and the light stays on, but if you then close the switch the light goes out. However the only way to configure the switch is through the app for sonoff and since its a zigbee device you need their hub to even try and connect it so I just gave up and I’m going to return it.

I did find the latest version of the Sonoff switch the MINIR4M which seems like the current version and from what I can tell it has the same logic level switch behavior so I’m going to order one of those and try again.