Zigbee Outdoor motion sensor - false alerts

Looking for an outdoor motion sensor, or something that detects a human at the front door.
I currently have a hue outdoor motion but it’s generating far too many false triggers due to changing light conditions, the sun coming in and out from behind clouds.
Suggestions for an alternative device or a means of eliminating the false alerts would be appreciated.

This has been discussed many times over the last nine years, and it’s always the same answer. It’s not the protocol, it’s the sensor type. All PIR motion sensors, whether they are zigbee, Z wave, Wi-Fi, thread, or whatever are going to have the same issues.

The best solution for most home automation cases is simply to narrow the field, typically using a tube over the sensor itself. That’s hard to do with the Hue because the attached light is so big, but it’s easy on a number of the others. Here’s one photo from a community member from back in 2017:


And here’s the discussion thread that goes with it. That specific brand is no longer available, but again, the brand doesn’t matter. It’s a tube idea that reduces the number of false alerts.

Peq motion detector for outdoor, a good idea? - #13 by eric182

People have also done something similar with the rectangular sensors by using tape to block off the top and bottom of the lens, which helps avoid sky and ground false triggers.


And here’s the discussion thread on that. Again, many of those brands are no longer available, and the notification methods would be different with the current architecture, but the problem and the tape solution are common to many brands.

The other alternative is to create a zone with multiple motion sensors, and only recognize an alert when you get reports from multiple sensors at once. That’s doable, but obviously costs a lot more money since you typically need three or four sensors to cover a zone.

Camera-based sensors, particularly those that can detect people, tend to have far fewer false alerts. But again, cost more.

I have successfully used the tape method on the Hue sensors, together with considered positioning (aimed away from plain walls for example) it has worked pretty well :+1:

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Thanks for this.
In my scenario the sensor is placed under a pitched roof of the porch, it’s effectively pointing toward the front door. There’s no foliage or even sky in its field of view.
I think the issue is basically the changes in sunlight hitting the front door. I don’t think narrowing the field of view with a tube would work in this instance since the entire area has the sunlight changes.
It’s fine on an overcast or even a clear sunny day. It’s the cloudy sunny day with the clouds on the move which causes the problem.
I don’t think multiple sensors would help much either as they would all suffer from changing light patterns in a relatively small area. I remember in days of old there used to be senors that were light beam based with a transmitter and a mirror reflecting back, I think elevator doors used to use that type. Something that works on that principle that triggered when the beam was broken would be idea, but I suspect no such device exists

These exist, they are called Trip beams. Most garage doors use them to determine that the space is clear. They are also used in people counter devices. They’ve been discussed in the past a couple of times, Dakota make some which are used for driveway alerts. Integration with smartthings is usually a little goofy, but can be done.

I’m pretty sure they were discussed in one of the two threads I just linked to.

OK, yes, trip beams were mentioned, but only briefly in previous link. The following thread discusses them in detail.

Some people call them “laser beams“ probably because they look like laser beams in movies, but they aren’t, they are almost all IR, and a few are sonar.

The following thread is a detailed discussion. Of course specific devices and any Groovy code will be out of date, but the basic idea still applies, and some of the brands, like Dakota, are certainly still available. Then you connect that to something that can communicate with smartthings, typically a dry contact device.

Here’s discussion of a version that’s still available:

Looking to Connect IR Beam Sensor to Flood Lights - #4 by krlaframboise

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Thanks for this, I’ll investigate further. I was hoping for something zigbee and seamless. I think all the dry contact sensors appear to be z wave. I looked at the guard line driveway sensor which as 12v outputs so that adds complexity too. Food for thought

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