Garage Door Opener
Installing a Garage Door Opener was fairly simple, but then I was left with one more remote control on my key ring, and I also needed to remember to turn the alarm on and off properly. I was always scared of coming home at 2am and having the alarm turn on because I forgot to turn off the alarm. To solve this problem, I decided to use my alarm system to control the garage door. I can still use the garage door remote, but now I can use the remote that came with my alarm system. The Alarm is a NESS/ELK M1(G), and has the ability to do some basic home automation. I purchased it because it came with an Ethernet interface, but that is another story.
The remote for the device is fairly simple, with four buttons. The locked and unlocked padlocks are fairly obvious, but what about the red and blue buttons. As my alarm installing friend commented, goodness only knows what their function is. In reality, with the M1(G), these buttons are programmable,
Controlling The Garage Door Opener
The Garage Door Opener I have was made by Chamberlain, and has the ability to attach a remote switch to open or close the garage door. I knew this needed to be a low voltage contact, so I wired up a switch across these two contacts and pushed it. Sure enough, the garage door opened and closed. Even though this was a low voltage, I really was not sure of the electrical properties, so I decided to conect up via a relay to provide some isolation in case something went wrong. You can see the case the relay is installed in if you examine the photo below.
My alarm system also had some spare relay outputs, so I wired one of these up so that the relay at the garage door opener was energized by 12 volts when the one in the alarm was energized.
Once this was done, it was a simple job to write a couple of rules to turn the alarm on and off as well as opening or closing the garage door when the red or blue buttons are pressed. The only thing with this is that the alarm has no idea if the garage door is open or not, so just toggles the state. A future enhacement might be to put a sensor on the garage door, only sending through the signal to the garage door if it is not in the right state.