Re: Quiet, 24VDC Motion Detector?

[Frank Olson <Use_the_email_links@xxxxxxxxxxxxxxxxxxxxxx>]

chsvideo@xxxxxxxxxxx wrote:
> Hi All,
>
> I haven't lurked around here for a while, but I now have a question
> that I think this group can help me with, so without further delay...
>
> Any suggestions for a motion detector that is
> a) Inexpensive,
> b) Operates on 24 Volts DC
> c) Is silent/very quiet?
>
> This would be used for detecting activity in a room (and due to the
> geometry of the room, I'll be using at least 3, which is why "the
> cheaper the better" is becomming my mantre here). I don't need pet
> imunity, I don't need tamper contacts, I don't need a walk test LED.
>
> Straight PIR is fine by me, and I don't need microwave. Contacts can be
> normally open or normally closed.
>
> If there isn't such a thing as a "Cheap, quiet 24 volt motion detector"
> I could make a "Cheap quiet 12 volt motion detector" work, but that
> would mean adding additional power supplies which I'd like to avoid.
> Large emphasis on QUIET. I used a old(er) FBII PIR for my
> proof-of-concept and -- this may sound wacky, but -- the sound of the
> relay clicking on and off drove me batty.
>
> Bonus points if it can be purchased at retail in the Cleveland, Ohio
> area.
>
> Thanks,
>
> Lincoln
>


The only PIR that I've used that operates at a range between 12 and 28
VDC is Securitron's "Rex" (you can source information on one here:
http://store.yahoo.com/853111/secheavdutex.html).  DSC manufactures a
unit they call the "T-REX", but I can't get my hands on the manual at
the moment and don't recall if it can handle 24 volts.  Either way
though, they're both noisy suckers (and used as a request to exit PIR on
buildings with access control).  I figure your chances of finding one to
suite your particular application are pretty slim.  I'd suggest "biting
the bullet" and using a 12 VDC power supply and source a quiet PIR like
the Paradox DG-75 from a Dealer in your area.

Good luck!