Nest Protect "Wired" Integration

Hey Guys,

I would like to integrate my Nest Protect with a Arduino/Konnected/RPI/etc that can communicate with SmartThings/Hubitat. I took one of my Nest Protects apart (battery version) to determine the ideal method for physical integration.

  • Tap into the siren (EFM 290edfp)

  • Put a color sensor that can tell ST/Hubitat when the status lights turns red (indicating an emergency).

I tapped into the siren and connected a voltmeter to see what kind of behavior I get. Here is a video:

As you can see the siren turns on and off so it is hard to see what the voltage reading is.

What are you thoughts - can I integrate this with a Arduino board (like the ESP8266)?

Thought I would tag some of the experts to this post :grin: @Ryan780 @ogiewon @JDRoberts

Why don’t you just use an audio sensor made for this purpose, like the zwave Ecolink Firefighter?

You only need one for as far as it can hear. One for most homes, sometimes one for each floor for very large homes or ones made of Adobe or brick.


Thanks for sharing. Will order this

1 Like

Just in case others are reading this, I should mention that this will only work with the US format nest protects, it’s listening for a very specific audio pattern. It won’t work with nest protects or other smoke sensors in England as different countries have different smoke sensor audio patterns.

1 Like

Awesome! Hopefully it is reliable - does it also work with Hubitat.

It should work with the classical app right?

It’s officially supported, so it should work with both apps.

I don’t know about Hubitat.

1 Like

Great! Only concern now is that the Nest Protect talks between the siren alerts…hopefully that doesn’t throw it off.

I was able to integrate this with ST using a NodeMCU (on Konnected) by simply connecting the terminals going from the Nest Protect’s siren to the ESP8226 board. I had to disable the internal pullup resistor on the Konnected board.

I added a voltage sensor (as direct connection was resulting in false alerts). [RELEASE] ST_Anything v2.9.7 - Arduino/ESP8266/ESP32 to ST via ThingShield, Ethernet, or WiFi

This is a lot more stable!