Looking for perimeter / infrared beam sensor

Hi everyone.

Last weekend some criminal decided to enter my yard in the middle of the night and tried taking out my lighting to potentially prepare a break in. Scary stuff.

Now I coupled my Hue outdoor motion sensors to my alarm, but it’s giving too many false alarms cause they detect cats/bats/birds as well. So I’m looking for solutions. I was thinking to add some perimeter sensors and hang them on like 1m height on the only entries around my perimeter. Much like garage door safety sensors aka infrared beam sensors; narrow infrared beam coming out 1 end, and detected by other end. When the receiving end does not detect it anymore (something standing in front of the lightbeam), it sends a signal. But I see there aren’t really any ready-to-use zigbee (preferred) sensors like this, at least not that i’ve found.

So I’m wondering if anybody has any tips of making something like this themselves, or maybe someone has a much better / easier solution. Feedback would be much appreciated.

It has to be weatherproof by the way, since it is about protecting entry to my yard.

Idea I had myself was maybe buy some Hue motion sensors (outdoor) and make small wooden boxes around it with on the center front a tiny hole or tube in front of the sensor, to narrow the field of view making it act like a (one way) beam sensor. But I have no clue if that would work. Anybody any ideas? Let me know. Much appreciated.

I’ve looked into this extensively some time ago (we had the same issue, some random guy walking up on the driveway to check out our cars in the middle of the night :grimacing:).

Most perimeter sensors require a fixed power supply, because they transmit an IR signal all the time, which would drain a battery too quickly. There are some sensors that can charge via built-in solar panels, but they are quite expensive and I wonder if they are able to keep the battery topped up enough during the darker parts of the year (also, cheap perimeter sensors from Aliexpress and the likes aren’t very reliable, they often miss the beam being broken if you walk through them too fast).

If a fixed power supply isn’t an issue for you, then most of these sensors have a built-in relay that gets activated when the beam is crossed. Then a common trick is to use a Zigbee contact sensor, solder some wires to it, and switch those wires with the perimeter sensor relay (see this page, for example).

Alternatively, placing a motion sensor in a confined space to limit its FoV works too, although in my experience they are more prone to false positives that way. Also be aware that insects usually like boxes like that :wink:

Eventually I settled for using a security camera with built-in person detection, which works very reliably. I still have a few motion sensors scattered around the garden, but they are mostly used to turn on the lights when we walk outside or have visitors.

I use commercial break beam sensors that I acquired at very low cost from auction sites. No false alarms, quite happy. Wired at both end for power and dry contact output. Not sure ZigBee or Z-Wave would be appropriate for this application.

There is quite a lot of differences in the DIY modelling you described the main being that they use two beams separated by a few inches. Both beams require breaking to alarm. This protects against false alarms from falling or blowing leaves etc. They use modulated IR beam(s) to avoid issues with sunlight and more determined intruders.

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What about a netatmo presence? AI assisted outdoor camera with floodlight.
I have some Netatmo welcome’s in the house, don’t have the outdoor variant yet. but the detection is pretty accurate, (facial recognition, animal, movement, person,…)
could set it to trigger only when it sees an unknown person.

Not only do you have a deterrent then but also video footage of who it is