Using existing Home Security System (Honeywell, Vista, etc) Sensors with Smartthings


Hey Brian,
any chance you’d be willing to give a quick tutorial on which wires to connect to in order to send the alarm output of my current wired alarm system to SmartThings via simple open/closed (door/window) sensor?

I have a Vista 15PMT monitored by Monitronics. For now, we will continue with the paid monitoring service, but I am very interested in making it SMART (to whatever degree is possible and practical at each stage of financial feasibility). So, since the budget is low-to-nothing at present, I just got a simple open/closed sensor for 20 bucks.

I connected wires to the included on-board terminals, and it triggers when shorted. So, I know how that part works.

I also took a look at the motherboard of the Vista 15PMT as well as the provided diagram.
Since I only have a single input sensor, my plan for now is to simply connect to the alarm output (So, when it triggers, I won’t know which ‘zone’ or smart monitor set it off, but I will at least know it’s been triggered; and can work on the rest as time goes on and as budget allows).

I see the two wires related to the alarm output. I’m just not quite sure how to connect. Will I be connecting the two poles of the sensor to the two wires of the alarm output and that’s it (i.e. doesn’t matter which one connects to which side, etc), or is there a particular way it needs to be done?

Of course, I could just start trying things, but I figured I’d check in here, in case it’s easy to point me in the right direction.

Do not connect your sensor to the panel’s output. The sensor’s auxiliary input is meant only for non-energized contacts, like reed switches. Panel’s output is typically 12V and will likely damage your sensor. You need to galvanically isolate the sensor from the panel using either relay or optocoupler.


Thanks. I guess I’ve seen this mentioned elsewhere, but missed it. Now I think I get it.
So, there is too much power coming off the alarm output (i.e. enough to power a siren, etc) for the smart sensor to handle, and that may burn it out/etc.

Where is the best resource to learn about exactly what is needed as far as parts and how to connect it all,etc?
Is it just a matter of going to Home Depot (or the local electronics surplus shop) and finding the right guy with this kind of knowledge, or what?

I’ve been reading a lot of threads on this, and have concerns about how well the Honeywell panels work with ST… In particular the contact closures are not properly reported to the panels, just contact opens, and therefore it’s hard to have ST stay in sync (via Evl-3)

… Or are your ST triggers only really concerned with the “open” events so you don’t really care about the “closed” events and having ST properly reflect status??

There can be a 1-2 second delay on update. The best way to understand the delay, open a door and watch how long it takes for the panel to trigger an alarm. Add about a half a second for the conversion from panel through ST card, etc.

I haven’t had any syncing issues on my setup and I’ve heard from many that the latest branch that has been written by other people in the community is far better than mine.

Noticed this in the deals thread…

I have a similar question. I have a Honeywell Alarm System and am in the midst of setting up home automation and have leaned toward Insteon products to play with Apple’s HomeKit. I am wanting to use some of Insteon’s open/close sensors with my alarm system and kinda kill two birds with one stone by adding more functionality to my alarm system and tie them in with my list of smart things. On a side note, I realize that these sensors aren’t currently compatible with Insteon’s HomeKit Hub +, but I’m hopeful that will change. I’m told by my alarm company that the sensors have to be by Honeywell to work with their wireless receiver. I’ve not seen anything that contradicts what I was told, but truth be told I’ve not seen much on this topic at all.

I have a bosh system unmonitored but we use it locally. I really jus want ST to know we armed it to trigger Goodbye routine as well as disarm for I’m Back routine. If there was some way for a non programmer to make this work I’d really appreciate the guidance. I’m willing to spend money but don’t want to replace the whole system if I don’t need to do that.

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Does your Bosch system have an output that can be configured to switch when the system is armed?

If it does, it might be possible to wire a (volt free) output into a Fibaro Door/Window sensor (they are designed to allow this type of use) which would give you z-wave reporting into SmartThings.

Alternatively if you have two outputs, such as an armed status, and an alarm status, then you could use Fibaro UBS Z-Wave and wire them both in. Then you would also have alarm status reporting in SmartThings. This sensor would need a 12v supply which you may be able to pull from your alarm panel.

As a bonus, both these sensors can have a cheap DS18B20 temperature chip wired in if that’s useful.

Thanks @djtucker, I want to make this happen and a armed status would be great as I assume I could run a rule to set security on ST. Too bad the keypad couldn’t be hacked to feed ST in addition to the visual LED message.

Here’s my security system brain:

Not sure if anyone recognizes this system enough to point me in the right direction.

Again, I think I want the ST automations and notifications running on top of the more traditional security that only triggers when a real intrusion occurs. I’m sure I’d create a monster if I started playing with rules and automations across all cameras and hard wired sensors and end up like I did when first using dropcams and ultimately turned off all notifications due to overload. It’s all a balance but getting a basic status off an existing security system would seem to me to be a critical element for a win for these platforms.

Is that a Bosch D2212B ?

David @djtucker
That looks like my system but the wiring and relays is over my head. Perhaps a primer on this type of connect with the Fibaro sensor. I’m interested in trying to figure this out but don’t want to make a mistake and short something out. Are there any guides or even paid consultants that would be a good fit for me at this juncture?

Hmm, not sure. I’m not familiar with that system personally - just found it through a google search on the main controller chip from your picture. My own (non-US) Bosch system, is user-programmable and has volt-free NC or NO output circuits that can be configured to report different items, such as the arm/disarm status, so I don’t have to go through too much manual build to get this working.

I am based in the UK, so I’m afraid I would not know what professional support might be available in US, nor the code restrictions, if any, on opening up and rewiring the alarm system. You definitely need to be confident (or find someone competent) with fiddling around inside the panel (and the necessary programming) to get the right outputs available.

What I can say, is that if you can get get volt-free (potential free) NC or NO circuit connections out of your alarm, which switch over when the system is armed/disarmed, it should be easy to get that signal into SmartThings through a Fibaro door/window sensor. If you can get two circuits, the second one switching (also volt-free) when the alarm is in the alarmed state, then you could get that into SmartThings using either a second Fibaro door/window sensor, or you can use a single Fibaro Universal Binary Sensor (UBS) to get both reporting connections into SmartThings with a single device. I really dont know how easy it would be to get/hack those connections out of your panel…probably would require some additional relays if the board does not natively support this kind of outputs.

Good luck

@sgnihttrams, your post goes back awhile. Did you ever get it working? I think I want to do what you were wanting. I want to have a few zwave door sensors wired by my security panel to a few zones and have them triggered by the already hardwired sensors. I want to still be able to use my alarm system as normal. I just want the added zwave reporting too. I know @geko was helping you a bit. But the post just stopped. This seems like it should be a simple thing to do. And relatively standard for most panels.

Unfortunately, with so many other issues to deal with at the time that didn’t take any wiring or anything, I put it on the shelf.

I did get a couple simple relays that I was going to use for doing this as well as integrating my wired-together smoke alarms, but haven’t taken the time to get back to it yet.

Someday, I will probably go through it all again, and buy whatever is needed to just integrate it directly.
However, if you get anything going, please let us know.

Just bought one of the Fibaro universal sensors, I knew this was dual input but now I have it can see it’s much more than that.
It’s pretty much designed to sit in existing wired motion sensors or at control panel, pass the alarms on to the wired alarm but also turn the wired sensor into a z-wave device. I did play about with interfacing my Honeywell Galaxy 16 alarm via ethernet before- not easy, difficult to get motion features right and has notable lag. These Fib mini pcb’s really do provide an elegant solution.
You get to use 8-30 volt power from the alarm, choose better microwave/ PIR detectors than available for z-wave, and add temperature sensors if you want. Wish I’d know before I bought the “toy” Smartthings/ Fibaro/ Aeon motion sensors!
If you have wired sensors these are really worth considering- have a look at their manual to see interface. Only downside I see is the z-wave plus version isn’t out yet- shouldn’t be too far away though going by other product timelines.

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Have you guys seen Kendrick Coleman’s Blog post on this matter?

I have bought an Arduino board and a Smarthings Shield and some day soon i am going to see about wiring to my existing Honeywell security system:

Just one quote:

One thing you may notice on the old security system is that there are resistors that limit the amount of power making a loop on each circuit. This was necessary on the old system because the sensors may have been ruined if too much current was running through them.

Obviously, the guy has no clue how sensors are wired in the “old-school” security system and what resistor are really for. Connecting sensors to digital inputs will work, but it’s a naive approach to say the least. :sunglasses:

Obviously, the guy has no clue how sensors are wired in the “old-school” security system and what resistor are really for. Connecting sensors to digital inputs will work, but it’s a naive approach to say the least. :sunglasses:

Hmm, speaking from a place of total ignorance here, what would be the better approach?

I am trying to understand how Kendrick did what he did here, I even bought a SainSmart Board and a SmartThings Shield hoping to try this myself, but its a bit intimidating since I have never monkeyed with a security panel nor an Arduino kit before.

Professional alarm systems use analog inputs that can detect three distinct states: open, close and tamper. Sure, you can wire sensors to digital inputs and forgo resistors, but your alarm won’t be able do detect tamper condition.