A scope for installing PIR?

I need some help from you pros. I'm staring at an assessment question that
says something like this: "when installing a motion sensor in an odd-shaped
room, scope the perimeter and eliminate obstructions."

I'm assuming there is a device that I would look through that gives me some
idea of what the PIR would see. But I can't sniff out anything on the web to
clarify this. I've given this a good try, and far too much time, but I can't
find a link to such a device. Does anyone know where I'd find one?

-John O

 

close one eye and don't move your head is a approximation of what your
PIR will 'see', unless your have a 'hallway lens' on it.

 

I need some help from you pros. I'm staring at an assessment question

Now that's what I would do, too. At one time I had a pretty good eye for
selecting the proper lens for my Canon A-1. But, does someone sell a 'scope
a room' tool?

-John O

 

Sir, there is no such device to my knowledge. Far more likely this is simply
a poorly worded statement that is trying to tell you go around the room and
make note of obstructions that would prevent the device from fully "seeing"
the room or area you are trying to cover.

Ideally, locate the motion on an interior wall that is also looking inwards
and away from heating vents, and streaming sunlight coming in from windows.
Follow the manufacturers recommendations to the letter, and it might also be
wise to set the device to the least sensitive setting, assuming your device
will allow for. You generally don't want motions set too sensitively, since
the poor ones anyway, can false alarm due to certain environmental
situations.

Think of a motion like a glass of water, full completely, with the meniscus
in a positive mode. If you literally breathe on the motion, it will spill
water (ie: alarm). With the better motions,or motions set to a less
sensitive setting, think of them as that same glass of water, but with the
meniscus in a negative mode. They will handle a little nudge without
spilling water (ie: tripping the alarm). However, any real presence of a
warm body is like smashing the glass with a hammer....

R.H.Campbell
Home Security Metal Products
Ottawa, Ontario, Canada
www.homemetal.com

 

been having knee problems?

I need a doctor to tell me what that means

 

Sir, there is no such device to my knowledge. Far more likely this is

That is entirely possible (the poorly worded part). Interestingly, I'm told
this phrase appears in a certification exam offered by one of the major
vendor-neutral organizations. Looks like I may retain my faith that I can
search down *anything* on the Internet. LOL

Thanks for the explanation.

-John O

 

Hehe...yeah, I thought that might be the wrong spelling. But your get my
drift I'm sure....)

RHC

 

You're welcome. Feel free to post any other security related questions you
have. There are a multitude of professionals on this group with the full
breadth of scope of all matters relating to security. There will always be
someone who can give you an intelligent answer (right or wrong....))

R.H.Campbell
Home Security Metal Products
Ottawa, Ontario, Canada
www.homemetal.com

 

It comes with a left handed dike and a skyhook.

 

I'd think that this means the same thing as if someone told you to go
to a job site and "scope out" the job. Meaning, go take a look and see
what needs to be done. You wouldn't take a "job scope" to do this and
neither would you need a "PIR scope" to see if a motion detector would
work in any given area.

 

If I close one eye, I see dark.


I've tried contact lenses but never "hallway" lenses.

 

I think you are right. It's too bad that jargon like this made it into this
exam.

-John O

 

Most PIRs have a built in test meter. It is called a walk test LED.

Good point. I used to work down the hall from the guys that designed all the
Heath/Zenith stuff sold in the home stores, and those lights were on a few
of the better PIRs. ( I have tons of that stuff in my garage) Most just use
the lights to which they are normally attached, but the process is the same.

-John O

 

I need some help from you pros. I'm staring at

Not really. Just use your eye. Stand where the PIR will be mounted and
look for obstructions. Each PIR model has its own unique pattern of "fields
of view" (FOV's). After using a few you will become accustomed to their
characteristics. For now, check the coverage pattern in the installation
instructions as a guide.

Remember to verify that the detector is installed at the correct height as
specified in the manual. If it's too high you may miss nearby areas. If
it's too low the area of coverage will be reduced. Also, if you are using
"pet resistant" detectors, note that most of these require very careful
placement to avoid false alarms.

When designing a system note that it's usually unnecessary to cover every
square foot of the protected premises. Protect the places where a thief is
likely to move about, especially corridors, access to stairs (not usually
the stairs themselves though) and important target locations like the master
bedroom and family room if it's a residence.

--

Regards,
Robert L Bass

=============================>
Bass Home Electronics
2291 Pine View Circle
Sarasota · Florida · 34231
877-722-8900 Sales & Tech Support
http://www.bassburglaralarms.com
=============================>

 

I think, if I remember correctly, Sentrol used to sell this giant clip on mirror you were supposed to clip on the detector body while mounted and you could "see" the coverage area. Good idea, but totally impractical---since your head was usually in the way of the mirror...I think I used it twice.