How to Wire a Door Alarm

Select an alarm kit that has at least one door alarm sensor assembly. Attach the door sensor assembly on the door and door frame, using the screws that come with the unit. The typical assembly consists of two parts: a magnet that goes on the door and a magnetic sensor that goes on the door frame. If the back of the door can be seen, such as through a window or sidelight, place the sensor at the bottom of the door to better hide it from view.

Place the magnet part on the door itself, directly opposite the sensor and facing it. Drill corresponding holes and insert the screws for both door alarm units. The magnet itself needs no wiring, just the sensor. Plug the alarm wire into the side of the door alarm sensor, there is only one port on the sensor and the plug just pushes in.

Run the wire under a rug or in the seam of a carpet. Use a flat head screwdriver or putty knife to gently push the alarm wire down into the seam where the carpet meets the wall. Continue to run the wire until it reaches the central alarm hub, provided in the kit. Plug the wire into one of the sensor ports. The correct port should be labeled as such, and the plug goes in by hand. Install and power the hub according to the manufacturer's instructions. The alarm will ask for your security code, enter the code and follow the on-screen prompts to enable the door alarm. The door must be closed when this is done.