Re: Cheap and small Break Beam circuit ?

[ian.bird@xxxxxxxxxxxxxx]

As always Frank you spot the most interesting products ;-)

I may have to get some to play with as they may be the answer to the
perennial PIR problem. In my case in my kitchen where PIR's don't work
very well due to hanging washing, temperature fluctuations and an L shape.

Ian







"Frank Mc Alinden" <frankmc@xxxxxxx>
Sent by: ukha_d@xxxxxxx
12/07/2006 20:26
Please respond to ukha_d


To:     <ukha_d@xxxxxxx>
cc:     (bcc: Ian Bird/CV/Novartis)
Subject:        Re: [ukha_d] Cheap and small Break Beam circuit ?


Hi Marcus

If the break beams involve  having the tx and rx on opposite sides of the
door then maybe consider this little ultrasonic device........not as cheap

as a beam break but  onlt required on side of the door plus a serial
interface.......
http://www.maxbotix.com/

Gerry Duprey is currently developing a pic micro interface which will
handle
up to 12 of these and will do an xPL Plugin for it...........Im going to
use
2 of these to monitor my pond water level and also a water tank (when i
get
one)..
HTH
Frank


----- Original Message -----
From: "Marcus Warrington" <marcus.warrington@xxxxxxx>
To: <ukha_d@xxxxxxx>
Sent: Wednesday, July 12, 2006 11:37 PM
Subject: [ukha_d] Cheap and small Break Beam circuit ?


> Having now got all the lights (except the kitchen/Utility) on X10
> circuits I've now started to think about how to implement occupancy
> detection. Originally I was going to use ceiling mounted 360 degree
PIRs
> but having trailed them I find that they're sensitivity isn't up to
> detecting someone walk into a space in time to get the light on (not
> helped by the X10 comms latency). The only way I can get anywhere near
> is to mount them directly over the entranceway since they appear to be
> more sensitive directly underneath the sensor. So, next thought was to
> mount them centrally in the room but then use a break beam across the
> entranceway (door jam) as a primary trigger. So does anyone know a
small
> simple break beam device or circuit that I could install across a
> doorway. Needs to be small and sit relatively flush with the surface
> (the door jams are wood so I can rebate a little bit) and be easily
> connected to HomeVision.
>
> Marcus
>
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>
> Yahoo! Groups Links
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