Ok, Will do.. In reading more about this I'm thinking the Dual tech
motions might be overkill for my application.
This is for a dental/medical office. I can share with you the floorplan
and perhaps you can help me find the best location for the PIRs. I've
uploaded a copy of the floor plan. It is at
I was planning on installing 3 PIRs in this office.
(with north being up)
One PIR in the north east corner of Room 100 to cover the lobby. I
choose this location as to not aim it into the windows.
One PIR above door exiting room 120 to cover hallway 112.
One PIR above door exiting room 111 to cover other hallway 126
The one concern I have is that room 105 (to the east) is all storefront
type glass. I don't know if this will have any considerations on
selection of the PIR placed above door exiting room 120.
The two doors will have contacts, and there will be 3 glassbreaks.. One
by each door area, and one in the room 105 with the other windows. I may
also put one in room 104 as that also has large windows, but it is
a smaller room which is also opened to 105.
Those are perfectly good detectors. You might also want to look
at the Visonic K-980D. I've used tons of those in my own
installations and I've sold literally thousands of them to DIYers
over the years. They've give excellent service.
A very inexpensive model that I've used a few times and sold
hundreds of is the Paradox DG-75. It's a very reliable detector
with a small price tag.
There are lots of other good ones. The GE / Sentrol RCR series
(stands for "Range Controlled Radar") dual tech detectors have a
neat feature. You can adjust the range of the microwave sensor
to ignore stimuli outside the desired detection area.
I have a section of my website where I list motion detectors from
most of the major manufacturers. You may find it helpful.
Everything you've said up to this point is pretty much what I
would have done as well. The detector covering hallway 126
(below) can work if it's a short enough range so as not to "see"
the windows and if there's no chance of reflected sunlight,
headlights, etc., hitting the detector face.
As an alternative to the detector near 107 which protects hallway
126, have you considered installing a detector in the NE corner
of room 105. That would cover room 105 and almost half of
corridor 126 (assuming that the back of the L-shaped counter in
room 105 isn't very high. If the partition is too high, you
might consider placing a narrow angle detector on the wall above
the window near the SE corner of room 105.
According to the plans, it's ~40ft from that wall to the glass. Sunlight
isn't a possibility, but outside those windows is a parking lot, so
headlights are. Those windows will be tinted, so that could help. From
the wall to the parking spot would be over 50 feet.
Good call about the NE corner. The L shaped wall is a half wall going
about maybe 40 inches or so.
Is the ademco 998 a good all-around PIR?
Make sure you properly adjust any PIR looking towards the windows. Most
have a 40 foot range, but if the lenses are adjusted too high, they will
pick up headlights. In one installation we didn't have a choice about
where to mount the sensor. In this particular case we adjusted it for
max range and masked the upper portion of the lens that was facing the
The Ademco PIR's are certainly "good all-around". I haven't had any bad
experiences with them and we have them installed in about 20 accounts
(take-overs). I've settled on the Paradox detectors (won't install
Some folks swear by it. More folks might swear at it. :^)
I've never been particularly fond of Ademco's motion detectors.
I tried a few 998's years ago with less than stellar results --
too many unexplained falses and quit using them. I list them but
only because some people search for them. When they ask I
usually recommend something else.
You're most welcome.
Thanks. I don't think I'm going to aim it at the window afterall. Am
going to do one in the corner where the two windows come together facing
outward as Robert had suggested. This will give adequate protection to
Thanks again for the feedback.
I made it a practice to use dual tech detectors almost
everywhere, even when there were no pets around. There are a few
straight PIR's that I like though a dual tech is less likely to
false than a PIR (all other things being equal).
I may have already mentioned it but I like the Visonic K-980D for
most short to mid-range apps. If the detector needs to cover a
50-foot hallway, the Sentrol RCR-50 would be worth a look. If
for some reason you want a PIR only the Paradox DG75 does a
decent job at a reasonable cost.
Here's a URL (my website) for the GE / Sentrol RCR50
The prices on these are retail. You're in the trade so expect to
pay between 20 and 30% less at your distributor.
> > Hello,
> > Can someone please recommend a good PIR for use in an office
> > environment? No pet immunity is needed. I was looking at the DT-7450 or
> > the DT-7435.
> Those are perfectly good detectors. You might also want to look
> at the Visonic K-980D. I've used tons of those in my own
> installations and I've sold literally thousands of them to DIYers
> over the years. They've give excellent service.
Both detector are very good and reliable..
from the floor plan you provided I would put a pir in every room, that have
windows or door accessible from the outside,in know some will say its
overkill but think about it,when they are inside its much more easier to
crawl your way up to where you need then to crawl you way thru a broken
window,is you are not already detected...
and its not because there is a wall that someone already inside wont pass
through it,and then could "bypass" the protection,by accessing the main
my thinking is, protect every entry point,and then add 1 or 2 pir in
corridor,just in case
"James Russo" a écrit dans le message de news:
Be careful James.
I didn't look at your layout but if you use the RCR units in close
proximity to one another you're going to have false alarms. Microwave
units like these will set each other off. Don't let the controled Radar
adjustment fool you into thinking that the array will be contained. The
only thing that's happening is that the unit will not see a doppler
shift further out than you adust it for but that doesn't mean the
patten is being contained within that adjusted area. That is: If the
unit has a range of 50 feet and you set it for 19 feet, the array is
still reaching out to 50 feet and likely further. If it happens to
cross pattern with another unit .......... false alarms.
Also, units cannot be mounted back to back within two feet but I
wouldn't trust it even that close.