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Re: Window Sensors



On Sep 25, 12:48 pm, DigitalPimp <mark.stubblefi...@xxxxxxxxx> wrote:
> Hello Everyone:
> I'm trying to figure out what sensors to get for all of my windows.
> It seems when the pre-wire was done all of the holes that were drilled
> into the window were 1/2" and have a cap that has a hook inside that
> holds the pre-wire.  The other issue is the holes are directly below
> every single window's seal that runs across the bottom of the pane
> that moves up and down.  The window seal is sort of silver looking and
> is rectangular shaped.  The seal is about 1/4" thick on the short side
> of the rectangle and about 3/8" wide on the wide side of the
> rectangle.  So I have 2 questions:
>
> 1.  Does a 3/8" sensor fit into a 1/2" hole?  Is it OK to get a button
> type magnet and somehow affix it to the seal on the bottom of the
> window with glue or the like?
>
> 2.  Should I use pressure type switches for the window?  What can you
> recommend?  I have a feeling that since the sensor will be under the
> seal, it would be easy to insert something from outside and bypass the
> sensor by holding it down when opening the window.  This part worries
> me.
>
> On a side note, all of the doors were pre-drilled at 1/2" as well.
> Most of the doors have the holes at the top of the door (inside the
> door frame) and one has it on the side where the door handle is (yet
> again inside the door frame).  All of the doors are metal but one.
> What should I do for this?  I've seen the roller ball type switches,
> but also read they are prone to clogging.  I like the wheel ones, but
> haven't read many comments about them.
>
> TIA
> -Mark

After reading this thread again, I find that there were a few things
left unsaid.

First of all, who ever did the pre-wire, didn't have a clue about what
he was doing. I don't know if you've considered it, but if you went
through a builder for the pre wire, have you contacted him and asked
him to make
good on the poor job or at least get some compensation for your
upcoming and ongoing troubles with your alarm system? What did he
say?  If you contracted it directly, have you pursued it with the
contractor and what did they say? Did you ask either of them what
their plans were for the ? inch holes in the sills? Or perhaps you
just bought the house "as is"

No one has said this, but DO NOT use any kind of push button switch in
the sills of windows. They will inevitably jam with debris, grit,
paint .... you name it.

No one has mentioned that GRI also carries 1/4 inch rare earth magnets
that may align with the ? inch recessed contacts. Even though the ?
inch switch is larger than a 3/8s inch switch does not mean that you
need a larger magnet to make it operate. Generally speaking you can
pretty much count on the fact that now days, most switches use the
same size reed contact and require the same amount of magnetic pull to
activate them. You'd have to experiment, to be absolutely sure, but
I'm betting that the 1/4 inch rare earth mags, drilled beside and on
the inside of the weather strip, would be strong enough to close the ?
switch. GRI has two sizes .... 1/4" dia by 1/8" thick and 1/4" dia by
1/4' thick. The latter being the stronger of the two. If you've got
enough meat in the bottom of the sash to drill a 1/4 inch deep hole
with a brad point bit .... to recess the magnet, then I have no doubt
it would pull in the ?" switch.

I'd have to actually see the window and how and where the holes were
drilled, but if I were looking at the job, I would try to evaluate if
the wires could be redirected so that you might be able to consider
using surface mount contacts on the inside window sill, rather than
messing with the ? contacts that are going to be at least partially
exposed to the weather. ( ie the part of the switch that's on the
outer side of the window seal.)  I'd bet there's a possibility that
with an experienced installer with a practiced dill hand, a small wire
hole could be drilled between the inner window sill or ( if the window
has a raised lower lip on it) the inside edge of the window. A small
surface contact could be used instead of an ill placed, partially
exposed contact in the outer sill. Once the wire was re-routed, hole
plugs could be used to fill the ? holes, then caulked and painted.
Now days, there are many surface mount contacts that are so small as
to be almost unnoticeable.

The wires may be able to be re-routed to another hole drilled in the
right place in the sill, that would accommodate a 3/8 inch recessed
contact also. Again .... sealing up the ? hole.

With regard to the doors, I don't use the roller ball or roller wheel
switches. Eventually they will need replacing and they will likely jam
and you'll think the door is protected .... when it isn't.

There are ? recessed magnetic contacts that are made specifically for
metal doors. Actually they are normal ? contacts with heavy duty
magnets. Some/most(?)  have the switches and or the magnets spaced so
that they are as far away from the metal as possible.





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