SmartThings Community

Connected Smoke Alarms

Might need just a little more help I’m afraid. Take a look at the attached diagram.

I’m planning to wire as shown. i.e. 5G, 4H, 3B & 1F.

Is that correct?


So, 5G is blue, 4H is red, 3B is blue, 1F is yellow

Doesn’t matter which blue you use above. As I said… power it up with just 5G and 4H and get ST configured. Then touch the 2nd blue wire to the yellow wire and see if the ST sees that happening. Not sure how you test the relay in the Aico without having to first trip the fire alarm.

OK, all soldered in and I have it generating something when I short IN1 and GRD… although it’s just a debug message in the Live Logging console:

parsed 'zw device: 08, command: 9C02, payload: 08 00 00 00 00 ’ to result: [descriptionText:Smoke Alarm: SensorAlarmReport(seconds: 0, sensorState: 0, sensorType: 0, sourceNodeId: 8), isStateChange:false, displayed:false, linkText:Smoke Alarm]

I guess this points to a Device Handler / SmartApp issue now? I’m using the Stuart Buchanan’s (fuzzysb) device handler.

Nothing showing up on the device page in the smartthings app.

I bought the Kiddie Relays on Amazon but this DIY is beyond me. Ended up purchasing Nest Protects for the home

Anyone interested in purchasing the Kiddie Smoke and Carbon relays, please let me know


I’m looking at build a few of these to replace old hard wire ones in a house we just bought.

I tried going through all the pages but was looking for a “shopping list” of parts if possible. I see a lot of repurposing of existing alarms but I’m going to be starting from scratch.

If there is a suggestion of a hardwired smoke/CO2 detector, relay, switch, etc, I would really appreciate it. Also, if there a “how to pair to smart things guide”, that would be awesome since I’m still new to settling up SmartThings.


Currently the only hardwired smoke detector with an integration that I know of is the Nest Protect.

I’m thinking of working on a DTH for the brand new Lowe’s Halo (and Halo+), but they are not available in my area yet.

See the last post, works fine for them and will let it show up as a smoke sensor in the Smart Home Monitor.

Sorry to resurrect an old topic, what would stop this integration happening direct with the Radiolink module in the EI450? (and related radiolink devices).

Radiolink runs at EU ZWave frequency(868.4) so maybe there is something there? Or does it need to support specific protocols?

Not sure I follow your question. This integration is really about the smoke dectector relays that can be purchased that will report an event via normally open or closed when smoke is detected. You can then hook up the relays to a contact sensor that will report back to SmartThings. This said there are really no contact sensor, z-wave, or zigbee requirements at all. It’s a matter of selecting a contact sensor that will work with the smoke dector relay. Some have screw terminals to hook up wires internally and some people are choosing to solder wires to the board.

So the first thing needed is to see if your smoke dectors have relays and from there you can choose a contact sensor of your liking.

The detectors in my house are from a company called Aico, and they make a RadioLink module that allows you to link detectors which are difficult to cable together. The RadioLink module uses the same Z-Wave frequency (though unsure of protocol), so was hoping I could avoid the use of a contact sensor. Wondered if anybody knew a reason not to investigate?

I guess the first thing to do is see if the device shows up in SmartThings if you choose to add a new Thing…

I’m almost certain it’s proprietary. I have 5 wired aico and I intend to add another 4 radio snensors in a different part of the house. Ive always planned on adding a relay in one of them and then using a contact sensor to notify ST.

Yet to do it. If you prove me wrong please post back :slight_smile:

I will give the wireless integration a go and let you know if I get anything, though Aico are proving 100% useless so far!! Might be hard without understanding the protocol as my skills are not high enough to packet/protocol sniff and I think you are right that it is totally proprietary!
Do you know what is used on the signal wire? Is it just mains voltage high to trigger connected alarms, or far more likely is it 9v-12v in line with the battery backup? (Though that raises an interesting problem if a sparkie wires it up wrong as those voltages don’t mix well!) Also is there any signal sent down it about triggering unit or you’re of alarm? Or just high for on and low for off?

I did that same thing, works great. Had to hook up the door sensor to the relay switch provided by the alarm manufacturer.

I then created a custom smart app based on the open/close door app and changed things for smoke, along with the icon based on switch location. It all fit in the blue box, just barely, but works great on my wired sytem to send me a notification and text when smoke goes off.

Only downside is the relays only look for voltage changes on the smoke bit and not the CO or GAS, which we also have on some of these. I guess fire is most important for now!

I have universal security detectors wired in the house.

name: “Notify Me When”,
namespace: “smartthings”,
author: “SmartThings”,
description: “Get a push notification or text message when any of a variety of SmartThings is activated. Supports motion, contact, acceleration, moisture and presence sensors as well as switches.”,
category: “Convenience”,
iconUrl: “”,
iconX2Url: “

preferences {
section(“Choose one or more, when…”){
input “contact”, “capability.contactSensor”, title: “Contact Opens - No Fire”, required: false, multiple: true
input “contactClosed”, “capability.contactSensor”, title: “Contact Closes - Fire”, required: false, multiple: true

section("Send this message (optional, sends standard status message if not specified)"){
	input "messageText", "text", title: "Message Text", required: false
section("Via a push notification and/or an SMS message"){
	input "phone", "phone", title: "Phone Number (for SMS, optional)", required: false
	input "pushAndPhone", "enum", title: "Both Push and SMS?", required: false, metadata: [values: ["Yes","No"]]
section("Minimum time between messages (optional, defaults to every message)") {
	input "frequency", "decimal", title: "Minutes", required: false


def installed() {
log.debug "Installed with settings: ${settings}"

def updated() {
log.debug "Updated with settings: ${settings}"

def subscribeToEvents() {
subscribe(contact, “”, eventHandler)
subscribe(contactClosed, “contact.closed”, eventHandler)


def eventHandler(evt) {
if (frequency) {
def lastTime = state[evt.deviceId]
if (lastTime == null || now() - lastTime >= frequency * 60000) {
else {

private sendMessage(evt) {
def msg = messageText ?: defaultText(evt)
log.debug “$$evt.value, pushAndPhone:$pushAndPhone, ‘$msg’”

if (!phone || pushAndPhone != "No") {
	log.debug "sending push"
if (phone) {
	log.debug "sending SMS"
	sendSms(phone, msg)
if (frequency) {
	state[evt.deviceId] = now()


private defaultText(evt) {
if (evt.value == “Closed”) {
“Alert: Fire/CO Alarm Triggered”
else {
“Fire/CO Alarm OK”


private getInclu

1 Like

Good to know! Thanks for posting.

Anyone know if this will work with 12VDC alarm system smoke detectors, looks like it says it requires 120VAC. A little confused as it says it support up to 28VDC, but then in the instructions it says needs 120VAC to operate?

I am trying to connect an existing 12VDC wired smoke detectors to a NodeMCU 8266, but I need to supply the detectors with 12VDC and then have a way to communicate with the NodeMCU.

Edit: These are the detectors I have.

I dont see it addressed anywhere. I dont know if its assumed or if I’m missing it.

Has anyone addressed how this acts on power failure? I ran a RM4 inline with my detectors to an Ecolink sensor. Works fine with power, but the z-wave sensor does nothing once the breaker is tripped. The detectors still function properly, but the sensor does not trip.

I use the kidde sm120x, it doesn’t work when there’s no ac power. I assume the rm4 is the same. Your smoke/co detector has a battery backup, the relay that you wired in-line with it does not. Check the manual that came with it.

Any idea what it would take to make your DH work with the newest gen Monoprice Z-Wave Plus Door / Window Sensor?

I tried using your DH but it looks like per mannual the external contacts are disabled by default. The last page of the manual explains that the External Sensor is disabled by default, but it can be enabled by changing configuration parameter 0x01 to 0xFF. (0x00 is disabled).

Looks like @krlaframboise wrote a DH an update DH for the Monoprice Zwave Plus door / windows sensor here that supports enabling the external contact switch.

I was able to trip your DH to smoke using the included magnet, so it looks it still works as NO. Battery reporting also isn’t working.

Here’s a pic of the mannual with the supported z-wave command classes.

Let me know if I can provide logs or anything else.

I believe you may have me confused with someone else. I am not sure which device handler you are referring to. My posts above are just pictures of what I personally did and I didn’t include a device handler.