Pet-proof PIRs - any good?

IME, no.

The PIR responds to a rapid change in temperature as a warm blooded creature goes past whilst subtending a few degrees at the sensor.

I know from experience that a bat flying too close or sometimes a spider inside the works can set one off as a false alarm.

^ This ^

We had to switch to window/door contacts in our garage, due to false triggering by bats, despite much adjusting of the the PIR.

Most of the one's I've seen are as you say just less sensative or have the detector not aimed at floor level where pets are most likely to be arriving from. On amazon I've seen detectors called human detectors.

there was a discusion on farnell forums

OMRON do a thermal sensor that can detect stationary thermal objects as opp osed to standard PIR motion sensor that only detect motion. The OMRON D6T t hermal sensor is able to detect the presence of stationary humans by detect ing body heat, and can therefore be used to automatically switch off unnece ssary lighting, air conditioning, etc. when people are not present (regardl ess of whether they move or not).

----------------------------------------------------------- Luckily I know the perfect sensor for you. Just go to adafruit. This is the best sensor I could find.

although I;m still unsure as to the differnce beween any warm blooded anima l in the sensing range of a PIR

I have had no problems with the Texe3com petwise and cats.

By that, do you mean

do they give false alarms for pets?

or

do they give false non-alarms for humans?

Try the dual technology PIR/doppler ones?

It *was* a dual technology one.

A fair cop, 'twas badly phrased. I assumed they would all detect people but may not reliably "filter out" pets.

Thanks, that's good to know.

Which model or type?

I have never found any reliable as it really depends on closeness as well as animal size and speed. If you have lots of animals I can see all sorts of issues. around here apparently from conversations overheard between neighbours, Foxes and Badgers set most of them off whatever you use. However these are strictly not pets are they. Some people down near the railway say they get bothered by small deer as well. I'm assuming wildlife use the railway line as a kind of highway to pastures new. Brian

Isn't this getting a little OTT? Maybe the answer sis infra red light and a camera that is triggered, then the flood only set to come on after a couple of minutes but with your own over ride switch if you need light. at least that way you can tell if somebody is really going to burgle you first.. :-) Brian

These are internal PIRs, linked to the alarm.