Motion Decector False Alarms

[tmbrown97]

Ano - that's awesome! That's a new level of automation that I'm years from

 

[rleist]

Can insects trigger a PIR by crawling on the face of the unit or would they have to be on the inside right on top of the sensor?

I've had 2 false alarms in the two years I've had my system up. One was in the garage and the other was in the workshop behind the garage.

Could heat or humidity also cause issues that would generate a false alarm?

Thanks,
Rob

 

[ano]

Can insects trigger a PIR by crawling on the face of the unit or would they have to be on the inside right on top of the sensor?

I've had 2 false alarms in the two years I've had my system up. One was in the garage and the other was in the workshop behind the garage.

Could heat or humidity also cause issues that would generate a false alarm?

Thanks,
Rob

If it was me, I would only use motion detectors in your home, not in a garage or unheated area. Use door magnet switches.

I can't speak for other areas of the country, but in AZ we have spiders of all sizes, very small and very big. They love to live in spaces like motion detectors, and they move around most at night. Spiders are good, actually, so we try to get along. But once I have a motion detector false alarm, I replace. From experience, one motion detector false alarm usually leads to more. I've never been able to pin it on a spider, but it is plausible. I don't believe a spider on the outside would trip it unless it was a BIG spider, but even a very tiny spider walking across the sensor inside would definitely trip it. (Many years ago I was an engineer at a company that designed these.)

 

[Digger]

Motion detectors are sealed pretty well to minimize bugs from getting in but it is possible. A bug walking on the outside can trip it but there are ANSI/SIA standards that some detectors are designed to that won't (never tried to meet that standard myself). Another problem is drafts and that us why many detectors come with an epoxy to use to seal the wire entry hole when you install. A detector on an exterior wall can have a draft enter and false alarm. A detector that meets EN50131 (-2 or-3 I think) would also have been evaluated to minimize false alarms especially at the Grade 3 or higher level.

In a garage a beam device can work well unless a raccoon etc breaks in. Aleph makes some nice ones as do others I am sure. They are also affected less by temperature.