On Fri, 14 Sep 2012 15:34:12 -0700, Gunner wrote:

On Fri, 14 Sep 2012 05:42:45 -0400, "Michael A. Terrell"
wrote:



PIR doesn't work well at 100 F


Sure it does. You might not get the full 100' or so range, but if the
detector is set up with a proper fresnel lens detection grid...

Not necessarily, Guns.

PIRs work via differential thermal emission.
If the room emission is close enough to the body's emission, the
PIR does not see a difference between them, so it doesn't trigger.

You might find this of interest..its one of the better pages Ive found.

http://www.ladyada.net/learn/sensors/pir.html

That is stunningly good, in relation to a lot of Web info.

--Winston