On Thu, 15 Jan 2004 21:18:09 GMT, Harry Bloomfield
wrote:

On 15/01/2004 Mortimer opined:-
What sort of alarm system should I go for, PIRs seem simple to
source and install but are there any that ignore cats and only react
to humans?

No, but you could probably site them so that they wouldn't 'see' a cat
on the ground. Even a bit of black insulation tape is enough, when
placed across the lens to restrict the field of view of a PIR.

Sorry, this is rubbish. Pet Immune sensors are readily available, from
RS for one, and they work perfectly well. I fitted several in a house
with an extremely large active cat and never had it trigger them.

Typical specs:

"1 or 2 animals up to 13.4 Kg"
"Pet immunity up to 33 Kg a dog or 4 cats"

--
Niall