DSC Alarm Garage Door Opener

Connecting your garage door opener to a DSC PowerSeries alarm system is pretty simple and gives you the benefit of being able to close the door from your alarm system panel. If you have an EnvisaLink module installed in your alarm system, you can also control it from your phone anywhere in the world. Unfortunately, most modern garage door controllers are more than just a contact switch. For instance my LiftMaster Security+ 2.0 opener uses a serial data connection over the low power door switch lines. Still it is not too hard. If you have a "smart" garage door opener, here is how to do it for about $20:

Parts Needed

• Another Garage Door Opener Switch that matches your existing wired switch (mine was less than $20 on eBay)
• 12V relay, high level trigger ($1-$2 on eBay)

You kind of have to sort through eBay to find ones that are cheap and do the trick. you don't need opto-isolation. The ones in the picture below work well.

Instructions

1. Take the case off the garage door switch so you just have the PCB.
2. Solder 2 pieces of wire, each about 4" long to the contact switch legs. You may need to experiment to find which are only connected to each other when the button is pressed.
3. Connect the other end of each wire to the screw-down block on the relay module. One goes on the common "COM", and one goes on the normally-open "N/O" terminal, but it doesn't matter which is which.
4. Use double-stick foam tape to attach the relay to the garage door opener switch.
5. Run 2 wires from your alarm system control box PGM terminal to the garage door opener. I ran a cat5 cable, which left me with enough wires to add a magnetic switch on the garage door, a heat sensor on the garage ceiling (smoke detectors may give false alarms due to exhaust fumes), an auxiliary buzzer so that I can hear when the keypad sounder is beeping, and the connection to the garage door opener.
6. Solder or use a molex connector to connect the wires from the alarm system to the relay input header, one on IN and VCC, and one on GND, making sure to preserve the polarity from the alarm box.
7. Unplug your garage door opener and connect two 8" long wires from the screw terminals on the opener to the garage door opener terminals. Make sure to connect to the wired switch terminals and not the sensor terminals, and make sure to preserve the polarity listed on the switch. I had to add new machine screws and nuts since the original ones went into the switch's plastic case.
8. Then, match the switch to the opener by pressing the contact switch a few times.
9. Once it is working use double-stick tape to attach it to the opener, making sure not to short out anything on the metal opener cover.