Integrating Kidde Smoke / CO Sensors into SmartThings Properly

I would think it does report as smoke…it definitely will with the change I just made.

Hopefully enough people will say something and they will add it separately, it really should be.

Well that’s really weird. I saw your change and was quite confused. Okay for now I guess.

I am curious if anyone has found some sort of a relay that can be powered by 120v or a step down transformer similar to the battery eliminator that can be hard wired to standard 120v not plugged into an outlet

Other then the obvious power outage disadvantages are there any other negatives to not using batteries (like having to reset the system)?

Not sure what purpose you’re looking for, but the relays mentioned in the OP are connected to the same 120V wiring as a hardwired smoke/CO detector.

I don’t think I was very clear in my previous post. I am looking for a way to power the ecolink door sensors other then using a cr123a battery, preferably I would like to power the ecolink sensor from the 120v line. I referenced the battery eliminator above because it does accomplish that goal.

Two reasons I do not like the battery eliminators are; 1 they are cost prohibitive at over $50 each, and 2 they would require wiring in a 120v outlet to plug the brick transformer into.

The other idea I think might work but I’m uncertain about how exactly it would work would be to replace the ecolink sensor with a

Then connecting the orange (normal open) wire from the kiddie sm120x relay to the aux wire from the z-wave relay. All I want the z-wave relay to do is record the event. My concern is if the z-wave relay is activated in any way I would send voltage from the z-wave relay to the kiddie sm120x relay and in turn to the smoke alarms.

You will find in the sm120x instructions that it has a 9V DC wire as well. Like you I was hoping to hardwire the contact sensor. Unfortunately that 9v doesn’t supply 9v at load and drops to 2v which isn’t enough to power the contact sensor. So I ended up following what I had done with several other sensors which I documented here:

This is much cheaper than your battery eliminators which I had looked into.


Can anyone draw up a wiring diagram. I got all the parts but I wasn’t sure which wire to connect to where.

Take a look at this thread, which is actually linked to above.

Thanks a lot for this! So I assume this isn’t possible with battery only operated detectors? I don’t have mine hardwired in series. Could I integrate into the relay with only the orange wire?
The Kidde Smoke/CO2 detectors I have are interconnected wirelessly somehow. So if one goes off they all go off. and they’re all battery operated. I could hard wire the one in the basement but that wouldn’t have the other 2 upstairs in series on the same 120 line.

The sm120x needs to be wired to your 120V house wiring.

Yeah, the only option for battery powered ones that I know of is either replace them with ones that have Z wave Built-in or they make a plugin adapter that listens for the alarm frequency and can relay the information that way.

I have two of the battery powered zcombo smoke/co detectors, a Halo, and the sm120x wired to a dumb smoke detector and the ecolink z-wave contact sensor.

I also have a Leeo and a kidde remotelync, those are the two devices that listen for smoke or CO alarm sounds.

I’m pretty satisfied with my setup overall, although I did replace one zcombo after two false alarms (it triggered for no apparent reason each time). Could have been something simple like dust or something but I didn’t want to take any chances. I also find that the leeo is prone to calling other high-frequency sounds a smoke alarm when they’re really something else. It’s not terrible, but since I setup the kidde remotelync to help offset that, it hasn’t triggered any false alerts when the leeo did.

Since I have kids and pets in the home, I like to think I’m appropriately paranoid when it comes to remote monitoring of smoke/CO alarms. :slight_smile:

Sorry, one more question:
Since mine are interlinked wirelessly, could I hardwire one and terminate the white/black/orange before on that image it says 'to additional alarms’
Therefore, if the one upstairs goes off, it will wirelessly set off the only one in the basement that’s hardwired to the relay. it should work correct?

You can wire just one detector to the sm120x as long as the smoke/co detector has an interconnect wire. That’s how mine is setup. You don’t have to have other detectors wired in series.

But you’re saying you have a wired detector that has both wired and wireless interconnects? What’s the model of smoke/co detector you’re using?

Is there a video on how to add the Kidde Smoke and Carbon detector to Smartthing app?

The only device thats being paired with the ST hub and will show up in the ST app is the z-wave contact sensor that’s wired to the kidde relay device using the contact sensor’s external inputs. All that’s required to pair the contact sensor is to pull the battery tab and put the hub into pairing mode (assuming it’s a new contact sensor).

IS there a SMARTAPP you used to set up the lights? I can not seem to get the lights setup. I have other door/window sensors that are working in this way.

Thank you for all the info. I designed mine just like yours.

Smart Home Monitor can be set to turn lights on when a security or smoke alert is triggered.

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I’m confused? So if I use both Kidde relays, will I receive alerts for smoke and CO2? Or does just the smoke work? I hooked up both and outputted to two Aeotec dry contact sensors. I’m not getting anything…

Each Kiddie relay will trip it’s respective alert (black one is smoke, blue one is CO). If everything is wired to the contact switches correctly they should trigger when you test your smoke/co detector. If you install the device type handlers from Vseven you can then use the sensors in smart home monitor.