I have a bunch of outdoor motion sensors. Generally they work fine, but I've started to notice a pattern. If the ambient temperature is relatively close to a human body temperature, say 95-100°F, then they hardly work at all.
At first I was thinking it was a ZWave problem (as all my PIR sensors were originally ZWave ones). To test, I bought a bunch of Aqara motion sensors. They worked great when I installed them, but then I started noticing them occasionally reacting very slow or not at all. It wasn't until I started thinking about temperature when it all started making some sense.
Cool temperatures = instant detection
90-95°F= reduced range but still mostly works
95-100°F= reduced reliability. Often fails to detect unless you wave you hand directly in front of the device.
105+°F= working better again
Has anybody else noticed this phenomenon? Does anybody know of sensors which are less susceptible? My Aeotec Trisensor seems to work better than the Aqara ones in that 95-100°F range, but still has noticably worse performance than when the ambient temperature range is close to a human body temp.
Mmwave radar sensors shouldn’t suffer from this issue, but passive infrared sensors all rely on a temperature differential to detect motion. I don’t know that any of the mmwave sensors are truly ready for prime time, but reading through some of @kkossev’s posts may help you avoid buying a terrible one. I have one of these that averages ~800 events per hour and it’s not considered as spammy as some of the ones that are available. In comparison, my most active Hue motion sensor averages 38 events per hour.
This is the operational principle of the PIR sensors - they sense the temperature difference (the radiation in the infra-red spectrum) between the human body and the ambient temperature.
these have some additional features if you will, being that the signals aren't blocked by most construction materials, so they see through walls, stucco, glass, the lot, this can be good or annoying...
They are consistent in response irrespective of ambient and target temperatures.
The old surplus sensors they use in that device are rated to 122 degrees Fahrenheit. Ambient temperature could be lower than what the unit is experiencing. Maybe they are in direct sunlight or near a wall refracting lots of ir and heat? I had a similar sensor on a security system act up like yours has and it was resolved by putting a cover over it to shade the unit out of direct sunlight. Just a thought. Good luck with it. Let me know how it goes.
I just bought one and am using his driver. It seems to work OK. It's producing a LOT of traffic, but so far nothing seems to be affected. I think I accidentally bought one of the more terrible ones...
No all are shaded... Under the carport or an eave or something of the like. I started graphing random sensor data recently.. started noticing that when my carport motion sensors start reacting very slowly, the temp sensor in the carport is usually showing right about 97-99°, which really makes perfect sense, I just never really thought about it in depth before..
The one I’m using doesn’t look to be much chattier than my Samsung Zigbee 3.0 plug with power monitoring enabled, but a lot of laundry has been done in the past day.
Edit: I set lux threshold to 500, since I am not using it on this particular sensor. That did help cut down on some of the events.
This mmWave sensor is the device called "Test". It has generated quite a bit of traffic in the 15 hours it's been plugged in and connected to Hubitat...
Yes. unlucky you have got the short end of the stick with this TS0601 _TZE204_sxm7l9xa ...
The HE hub performance is not affected too much, as the driver tries to hide the unused spammy reports ... this way :
So this particular sensor seems to pick up a very narrow area BEHIND the sensor. I mounted it on the wall above the desk in my office. On the back side of the wall is the hallway and door to my daughter's bedroom. The sensor picks up anybody walking into my daughter's bedroom, even though it is behind the sensor and through the wall.
As soon as I saw how much debug logs were being written, I immediately disabled them. I am going to disable description logging too as this thing literally reports any 1lux difference in lighting which is crazy. I may just tape over the little hole for the light sensor..
This is also an expected 'side effect', actually a back-side effect...
The typical mmWave antenna radiation pattern is a cardioid, with the back side smashed a bit because of the PCB screening effect.
