I hadn’t seen this done before, so I decided to try it on my on. I knew nothing about the Honeywell Vista alarm system about three days ago, and my coding skills are garbage, so don’t let that deter you. A quick summary of what this is:
I’ve created a *very* simple way to interface an “older” alarm system with a “newer” home automation system. This could be expanded greatly, but my requirements were simple. 1) I wanted to be able to arm or disarm my alarm from anywhere in the world and 2) I wanted to be able to incorporate arm/disarm with some home automation (I.e., house arms automatically when deadbolt has been locked.)
I’m using Wink, but any home automation software/hub should work. Wink is a pretty locked down system, but I love the simplicity – it seems to always work, and I find the Wink Relays to be cool. However, if you think Wink is locked down, you haven’t met Honeywell alarm systems. You can get remote access for your panel, but expect to pay for it. I wanted to find a cheap one-time cost solution. I started by ordering a GE Outdoor Smart Switch, a Z-Wave enabled smart device. I chose this particular model because I was pretty sure the case would be big enough to house some additional electronics, and I wanted the set up to be clean. The Z-Wave switch has been modified and an Arduino (I’m actually using an ESP8266) checks the relay state on the Z-Wave switch. The ESP8266 is connected to the Arm Away and Disarm buttons on a Honeywell 5834 keyfob. So, how this works: In the home automation app of your choice, you pair this Z-Wave switch. When the switch is on, the ESP8266 reads that the relay inside of the Z-Wave switch is closed, and it outputs a simulated button press to the Honeywell 5834’s Arm Away button. When you turn the switch off from your home automation app, the opposite happens. The ESP8266 “sees” the relay open and outputs a simulated button press to the Honeywell 5834’s Disarm button. By creating a simple interface through Z-Wave, we have access to our alarms through our home automation apps.
How did I do it? Buy you a Honeywell 5834, a GE Outdoor Smart Switch, an Arduino compatible board of your choice (I’m using the ESP8266 NodeMCU so I can eventually make this a closed loop system), and a 5V USB wall charger.
Let’s begin. Start by opening up your GE Outdoor Smart Switch. It has a seam that goes all the way around – I took a pair of wire cutters and wedged them in the seam to open. Once opened, unscrew the electronics. Let’s take a look around. This design is actually pretty good. They’ve separated their high and low voltage boards, however, my cheap and dirty solution ruins that.
The easiest way that I found for interfacing reliably was checking the status of the relay. This allows us to keep the Smart Switch mostly intact – I wanted a near-foolproof way of making sure this would work reliably. I also originally tried using the 3.3V converter that’s built in to the Smart Switch, but the ESP8266’s initial power draw was too high. Instead of altering the Smart Switch’s converter, I simply used a 5V USB wall charger.