With wireless door sensors becoming inexpensive, it would be nice to have one that can work in all elements. I found one that has the ability to hook up an external dry contact sensor, but it was still only rated for indoor use. To deal with this, I built an outdoor enclosure to house the wireless receiver, and used an external magnetic reed sensor on the gate.
For the housing, Lowes has an outdoor-rated plastic box by Taymac. The box comes with three openings and a few fittings and covers. A multi-size pack of glands was from Amazon.
In my case, I didn’t want to use any of the included holes, and instead wanted to use a separate gland. The covers have slots for flathead screwdrivers, so a gland wouldn’t make a good seal. Given the Taymac boxes only come with two covers, I also needed a third cover (also found at Lowes).
I also used a piece of unopen corrugated tubing which covers the sensor wires.
I then drilled a hole to fit the gland.
Unfortunately the mounting end of the gland was pretty short and couldn’t be secured with the locking ring, so instead I used epoxy to secure it in place.
The sensor is mounted by drilling a hole through the board close to where the gate hinge is. Near the hinge, the door won’t swing much relative to the hinge so there’s no need to worry about the wind causing it to send false positives.
The magnet that activates the switch is mounted to the door. There are spacers to ensure the magnet is mounted close to the switch when it is closed.
From there, the assembly can be mounted to the fence so wiring and sealing can be completed. The box is mounted so the gland is higher than the sensor so water wouldn’t flow down into the box if any did manage to get into the tubing.
From there, I attached the sensor to the electronics. Then I used sealant to cover all the mating interfaces as an extra measure to make sure it is water-tight. This includes around the tubing/gland interface as well as in the end of the tube where the wires exit. It looks messy, but it will help seal things.
After the sealant has set, the electronics can be assembled and the door can be tested before placing the cover on the box.
Testing confirms it works well, and doesn’t falsely trigger when I shake the gate.
Final assembly. As you can see, it’s next to the wall of my house so I couldn’t hide the box around the corner easily. It will need to be accessed to change the battery occasionally. This is mounted behind the entrance, so no one should mess with it, though I might still tack down the cable so it’s not hanging out as much.