Supplementary PIRs

[chris_j_hunter]

thought this might be useful for others, too ...

we're pretty open-plan, meaning absence of doors (which help Cortex decide where we are with good certainty) and a need to add some logic of our own, here & there, to decipher multiple PIR sensing ...

all of which has highlighted some blind spots, causing some confusion & missed presences ...

meaning, a need for more PIRs ...

but how to add them easily & inconspicuously ...

then noticed these :

http://www.gmelectronic.com/pir-modu...22a-1-p754-294

price seems right, and they would need just a simple drilled hole & a short cable run to a convenient Idratek module's 15V supply & digital input ...

[Paul_B]

Chris,

I maybe being a bit thick but as you started this topic could you confirm if PIRs can face one another? In addition to the problem you describe I also have an added complication of trying to avoid presence detection of the family dog.

Paul

[Andrew Millne]

Thanks Chris, good find.

[chris_j_hunter]

no problem facing each other ...

of course there'd be no point in having two that always operated identically ...

some of our blind spots are caused by field of view limitations, some by range limitations, some by doors sometimes being open in-front of them ...

logic can include time differentiation, of course, so even if two broadly see the same, order of triggering can be taken into account - with care, given lags can be a bit variable, as when Cortex is a bit busy ...

[Paul_B]

Thanks Chris, one last question and sorry for hi-jacking the thread, have you a sensor array for going up or down stairs?

Paul

[chris_j_hunter]

not as such, 'though there's provision for later addition of beam-break sensors, we're not convinced would work advantageously ...

PIR sensors cover landings, and logic decodes multiple sensor inputs (open plan again) to decide when stair lights are needed ...

not working perfectly yet - blind spots !

[Paul_B]

Thanks Chris

[toscal]

@Paul B Do you know you can get pet friendly PIR sensors.

[Paul_B]

@Toscal yes thanks I am using some to replace the Idratek PIR units where our dog causes problems. The downside is they are slower to trigger for humans and so I probably need more to overlap to trigger on humans for HA and not the dog. The units I have chosen are Visonic Next+ K9-85

Paul

[toscal]

What setting are they on, from memory there is either a wire link you can move or a dip switch, to change the triggering level. I think its either 2 counts or 3 counts. It maybe near the one for the test led on or off function.