Re: PIR's: Why trip on two detects?

[Frank Olson <Use_the_email_links@xxxxxxxxxxxxxxxxxxxxxx>]

Jim wrote:
> Nomen Nescio wrote:
>
>>Jim said:
>>
>>
>>>>Offhand, I can't think of any dual tech that can be set to trip on either
>>>>PIR or MW, rather than both.  Which one are you thinking of?
>>>
>>>The Sentrol AR 435 for one and I think some of the Visonic dual tec's
>>>also.
>>
>>I know the AR 435 can be set for microwave-only, but that's not quite what
>>Frank was talking about originally.   He was mentioning a dual tec that
>>would go into alarm if either the PIR or the microwave was tripped.
>
>
>
> hmmm ..... Sorry ..... but I missed that.
>
>  > I don't know whether any of the Visonics do that.
>
> I don't know of any motion detector that does that.
>
>
>
>>I wouldn't think there'd be too much demand for it.  Instead of reducing
>>false alarms, such a detector would increase them, as anything that would
>>trip either technology would cause an alarm.
>
>
> Yeah, but I bet it would sell for a really low price!
>


On the Visonics, it'll do that in "test" or "set up" mode.  I came
across two installations on take-overs where the tech had left the
sensor in MW test mode (PIR off).  I wouldn't recommend leaving them
there personally.  You're not getting the "best bang for your buck" if
you do that (the benefit of using both technologies).

ISTR Racal (Chubb's parent company in the '80's) had a couple of dual
technology sensors you could set up that way thereby eliminating the
need to sell two different types of sensors.  Depending on the
environment, you could activate one, or both.  I don't remember the part
number, but I still have a some old price sheets around here somewhere.
  I'll look for 'em over the next couple of days and post the PN's.