Zwave or zigbee low volt relay switch / dry contact

My wife and I are both Deaf. We had a wireless doorbell system when button is pressed, it send a signal to several of my flasher receiver in the house to alert us that someone is at the door.

We recently purchased a doorbell camera and hook it up to a hub so when doorbell is pressed, an event is triggered. It works good so there are no issue with it.

But we been looking for a low voltage zwave or zigbee relay switch or dry contact so we can remove the button off the wireless transmitter and hook up the relay switch / dry contact that each time an event (doorbell camera pressed) then it will close contact on the wireless doorbell transmitter to flash our receiver lights.

There are few that we looked at in the 50 dollar range but it is an over kill for a battery powered wireless doorbell so is there any DIY small kit that is a zwave/zigbee battery power which will do a close contact on each event?

We wanted to be able to take the wireless doorbell circuity out of it housing and put it in a small project box long with the zwave or zigbee relay switch.

I have a zwave door / window sensor with an auxiliary dry contact.
But as with most things zwave, it’ll break your $50 limit

Isn’t door / windows sensor purpose is to detect when a contact is closed? I need something that will close a contact not detect it.

Hub can send a signal to the Ecolink door sensor to make a close contact (act like pressing a doorbell) ?

Oh no not in that direction sorry I misunderstood what you were looking for
You might be able to do it with a Shelly 1, if you powered it with a power adapter, it will work on 12v but you’d wanna verify it isn’t sending voltage out the switched part. If I get a chance later I’ll check one

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Shelly 1 is wifi correct? If you have one, please do check to see if it just a simple closed contact switch without any voltage sent … it might be what I am looking for but I do preferred zwave or zigbee version if it exists.

Thank you

Shelly1 does have a dry contact output between O(Output) and I(Input)
Only Shelly1 does this though, the others have a voltage output on O
I use Shelly1s this way, running on 12V with esphome (as well as using the SW connection for a binary sensor)

It may work for me then.

All I need to do it power it with a 12v adapter then connect I/O to replace the button on the wireless doorbell transmitter?

When an event occur, it’ll make a close contact acting like pressing a button on doorbell?

Yep I just checked… I was fiddling with mine as a doorbell replacement… so I had an old power supply wired up already… don’t laugh at how old it is … image


Yep, just set it up like that in epshome or use tasmota or standard firmaware and mqtt

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I have that power supply boxed up somewhere! LOL … you had to buy plug separately for it!

I am a Radio Shack fanboy when they used to sell those red boxed 2 dollars experiment kits. I was always asking for a new radio shack kits for my birthday when I was a young boy :slight_smile:

Also… I had to grind down a pair of tweezers to move the jumper… you may want to buy a pair of tiny ones…

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Yeah that the kind that has interchangeable ends for different size plugs… :slight_smile: my dad had about 6 of them I kept

Easier to just pop the lid off (be careful of the attached antenna though)

Thanks for that… now I know for the other one… it seemed like it might have been glued or something

Na, fingernail between the top and bottom and it pops right off. I broke the antenna cable on my first one so be aware of that, its quite short

So my plan was… I have old fashioned doorbell chimes with 10v transformer … I was going to put the Shelly in between the old transformer and the chime, and use the power supply for the Shelly to power the doorbell button (with light inside) … so pressing the button would close the relay and send power to the chime… didn’t look much more into it as i need new doorbell wire before I mess around as the stuff down there now is falling apart… anybody have input if that should work? (I also have front and side doorbells ) so I was thinking maybe Shelly 2.5 I think it is??

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Shelly devices for the most part require mains AC voltage for power, and all of the ones with power monitoring also require mains on the switch input pins (shelly1pm, shelly 2.5, shelly dimmer, others?).

There are many ways to read a doorbell signal. I use a hall sensor, arduino nano, and the HA serial sensor component to do it. This is great because I already use that nano for other analog readings (backup battery voltage, mains status, etc). For a simpler approach if you don’t need the extra IO, I like frenck’s method that uses the bell current to close a relay coil directly, then the relay contacts are measured by an esp:

Now operating a relay based on that doorbell signal is (or can be) totally independent of how you read that signal. All you need here is a relay device (dry contact may not even be needed). Yes most shelly’s may work, but I think the power monitoring and mains switch input are not ideal for this application (former is a waste, latter is a limitation on the install). A better choice IMHO would be a dry contact modified sonoff, or save time soldering and get a shelly 1 (not the PM kind!). Either of those can easily be installed/programmed to operate your flashing lights (via dry contacts) when the doorbell is pressed.

A side note, not sure what doorbell cam device you have or how you configured it in ha, but you might just be able to use the state change in HA to trigger the relay (no additional bell signal reading circuits required). That said, do you now have 2 buttons, the original bell and a camera/bell? If you just have the cam/bell and it’s firing events in HA, then all you really need is the shelly1 or modded sonoff (or similar dry-contact relay device).

Shelly 1 can run on 12v… as shown above… and have a switched input… which means the button press would close the relay…
I already have door sensors by the solenoid in the chime… but they sometimes move and don’t always trigger as they are very sensitive…

I have built this and that is not correct, the ESP reads the doorbell button and the ESP relay essentially replaces the old button. A power adapter is still needed for the ESP relay