Home alarm SmartThings integration

After having a conservatory fitted, and at the time not extending my home alarm to cover the door, I wanted to use a battery powered door switch to save disrupting my home decoration by running additional cables etc. (My alarm panel is in the garage at the front of the house and the conservatory at the back.)
Initially I looked at trying to add a commercial wireless door sensor to my home alarm, but these don’t have the reputation of being very reliable and are difficult to find in the UK

Then I got to thinking about using a z-wave door sensor and integrating my home alarm into SmartThings.

I want to set some ground rules here first and make a few statements.

  1. I don’t think SmartThings is reliable enough to use as the sole provider of intrusion security in my home – It’s just not good enough to replace the brain of my current, hardwired, alarm

  2. If the internet in my home goes out (unlikely as everything is on UPS) it’s still gotta work
    (with the exception of the conservatory door)

  3. Control for the system must remain with the wired alarm
    (Use of existing keypad entry/exit to facilitate Wife Approval Factor)

  4. If I get a bunch of false alarms then I’ll be in trouble with the wife!

  5. The existing alarm has a 12v dc battery backup so will still work for a while through a total power outage and might, with the relevant voltage regulator & circuit, be able to power the z-wave integration too.

My conservatory backs onto my lounge which is covered by the existing wired PIR so even if SmartThings is inactive the most an intruder could do without setting off the alarm is steal my conservatory coffee table & chairs! (this is the current setup without SmartThings)

Two main functional requirements:

• If SmartThings says a door is open or a motion sensor has tripped I want it to set off my home alarm (if this has been ‘armed’ with the keypad)

• If my home alarm goes off then I want SmartThings to tell me via some kind of notify app

Recently my existing alarm has been playing up a bit. (it is 12 years old now and is used daily)
After a few diagnostics it seems the panel needs replacing, though the PIRs and door switches appear to be ok.
So… the ideal time to replace the panel and integrate SmartThings!
If I work this out correctly then anyone can do it to ANY alarm panel

Phase 1 – Getting the alarm to tell SmartThings that something has tripped the alarm

Originally I thought to use Fibaro Door Sensors but at £40 per unit they are quite expensive
@NAVET604 replied to a different topic saying that he had used ‘wet’ sensors to interface a relay with SmartThings and since these are quite a bit cheaper in the UK than the door sensors at around £30 per unit, I am going use one of these

My thoughts on this changed after some consideration - What do I really want to know?


I can look at the panel to see which zone has been tripped, when I return home, so when I’m not at home all I want is to know that my alarm has been tripped and the siren is going off.

I have a good friend who is retired and lives 5 minutes away. He will check things out if I’m not at home.

So I just need to know when the siren is screaming… . This is easy, the siren is triggered by a 12v supply from the panel. So, connecting something to this supply will tell me when the panel has activated the siren.

Connecting a small relay to this supply can activate the water sensor to enable SmartThings alerts etc.
I powered the water sensor directly from the alarm panel via a little Chinese adjustable voltage regulator and connected this to a 12v relay, triggered by the supply to the siren

Phase 2 – Getting SmartThings to trip the alarm
Most wired house alarms use a continuous loop, per zone, which if broken will tell the alarm to scream until reset or the panel bell timer kicks in (about 20 mins in the UK)
The easiest way to interface SmartThings into the alarm is to use a separate zone loop and use a relay to break the loop via a SmartThings command.
Here I’m thinking to use an Aeon z-wave relay to break the loop (purely because I have a spare one lying around)
As the Aeon is on 240v ac and the loop contains 12v dc I will use an additional 240v relay to break the loop.
All mounted into a small project box:

This is my new panel - All ready to wire up!

During testing the alarm responded to the Aeon instantly and when the siren went off, the water sensor also responded almost instantly.
I’ll find or write a smartapp to tell me what is going on and I’ll probably just use ‘smart lighting’ to trigger the zone and tweak a couple of DTH to make it look right in SmartThings

I have No idea why all my pics are upside down!

I did something very similar with a standard Texacom alarm but used a zwave relay to trigger the panic button input, this sets the alarm off instantly. Now whenever I add a sensor or blink camera I just set them up to trigger the same relay and they are instantly integrated.

@jarm69 I thought about using the panic circuit loop, but wanted to be able to program delays etc. which I can for any zone on this panel
The instant integration is exactly what I am looking for!
As we have a couple of dogs, using smartthings motion sensors which I can switch on when we walk the dogs is an added benefit. (Can’t use the standard PIRs when they are around :slight_smile: )

you may know, using ST motion sensors to trigger your burglar alarm, is not good:

…1 Single-tech,
…2. they stop reporting for no apparent reason (for Gen2 / CR2045, I think it’s mostly battery quality and contacts corrosion),
…3 no supervision (unless you count on Device Health to work), and
…4 false motions for no discernable reason - seems to be 100% cloud ghosts. Maybe it’s extreme latency. Either way not reliable.

Still, it’s a nice trick for a non-critical zone to notify you, just not for triggering a siren.

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