Do they work through glass? I would like to find a unit that will
allow me to check temperatures in vacant stores through the
storefront.

http://shop.vendio.com/BROADSTONEPRO.../?s=1231846607

Like this.

Thanks!

Peter Wieck
Melrose Park, PA

It's not a silly question.

Regular glass supposedly reflects infrared, does it not? And these devices
measure infrared, is not so?

On Jan 14, 5:21*pm, "William Sommerwerck"
wrote:
It's not a silly question.

Regular glass supposedly reflects infrared, does it not? And these devices
measure infrared, is not so?

Actually, glass reflects or absorbs infra-red based on angle and
composition and coatings (if any). Were it to reflect (all of) it, a
lens would not be very good at starting fires in by concentrating
sunlight.

Further, these guns use a laser and some sort of sensing device - so,
I am trying to determine how good it would be at sensing say... a wall
temperature a few feet inside a building through a window.

Peter Wieck
Melrose Park, PA

"William Sommerwerck" wrote in
:

It's not a silly question.

Regular glass supposedly reflects infrared, does it not?

not all IR wavelengths.

And these
devices measure infrared, is not so?






--
Jim Yanik
jyanik
at
kua.net

wrote:
Do they work through glass? I would like to find a unit that will
allow me to check temperatures in vacant stores through the
storefront.

http://shop.vendio.com/BROADSTONEPRO.../?s=1231846607

Like this.

Thanks!

Peter Wieck
Melrose Park, PA

Based on the other answers, I think the best bet would be to get a
baseline--normal temp--and from there just look for a rise. IOW, it
might not measure actual temperature accurately, but the the consensus
seems to be that various types of glass will pass 'some' IR; so it might
be good enough to indicate a change. As long as you know what it
'should' read, you can tell if it's above normal.

Of course it will take some experimenting.

jak

wrote in message
...
On Jan 14, 5:21 pm, "William Sommerwerck"
wrote:
It's not a silly question.

Regular glass supposedly reflects infrared, does it not? And these devices
measure infrared, is not so?

Actually, glass reflects or absorbs infra-red based on angle and
composition and coatings (if any). Were it to reflect (all of) it, a
lens would not be very good at starting fires in by concentrating
sunlight.

Further, these guns use a laser and some sort of sensing device - so,
I am trying to determine how good it would be at sensing say... a wall
temperature a few feet inside a building through a window.

Peter Wieck
Melrose Park, PA



The laser is purely for aiming and is not involved in the measuement
process. Take a cup of coffey and try measuring its temp driectly and from
behind some different glass types - some glass may be tempered or laminated
which may affect readings (guessing here).

wrote in message
...
Do they work through glass? I would like to find a unit that will
allow me to check temperatures in vacant stores through the
storefront.

http://shop.vendio.com/BROADSTONEPRO.../?s=1231846607

Like this.

Thanks!

Peter Wieck
Melrose Park, PA


PIR detectors don't work through glass


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

In article
,
wrote:
Do they work through glass? I would like to find a unit that will
allow me to check temperatures in vacant stores through the
storefront.

http://shop.vendio.com/BROADSTONEPRO.../?s=1231846607

I have a similar looking one in the UK - and that does work through glass
(or at least some types). For example it gives the same reading through my
glass oven door as with it open (checking the oven thermostat). But things
*may* be different with some types of glass designed to reflect the sun's
heat.

I'd also say that looks a high price for these things - perhaps because
it's sold for automotive use. Check Radio Shack or Ebay etc for the same
thing - in the UK 25 gbp is a guide price.

--
*I used to have an open mind but my brains kept falling out *

Dave Plowman London SW
To e-mail, change noise into sound.

Actually, glass reflects or absorbs infra-red based on angle and
composition and coatings (if any). Were it to reflect (all of) it, a
lens would not be very good at starting fires in by concentrating
sunlight.

You've got to be kidding. Where did you learn "science"?

On Jan 15, 4:40*am, "Dave Plowman (News)"
wrote:

I'd also say that looks a high price for these things - perhaps because
it's sold for automotive use. Check Radio Shack or Ebay etc for the same
thing - in the UK 25 gbp is a guide price.

Yep. I just linked to that as it gave a fair description of the unit.
Very similar units may be had at eBay for less than US$30 including
shipping. I am going to check in several local supply houses as well.
I am willing to pay a premium to find something - MAYBE - made in the
USA.

Thanks for the actual answer to the actual question.

Peter Wieck
Melrose Park, PA

In article , " wrote:
Do they work through glass? I would like to find a unit that will
allow me to check temperatures in vacant stores through the
storefront.

http://shop.vendio.com/BROADSTONEPRO.../?s=1231846607

Like this.

Thanks!

Peter Wieck
Melrose Park, PA

From experiance, its not going to work well. You will get some
relative indication of a general temperature of the inside comparing
different stores.

greg

" writes:

Do they work through glass? I would like to find a unit that will
allow me to check temperatures in vacant stores through the
storefront.

http://shop.vendio.com/BROADSTONEPRO.../?s=1231846607

Like this.

Thanks!

Peter Wieck
Melrose Park, PA

I just checked with my very similar gun, and it shows the surface
temperature of the window glass. The outside temp is currently around
-5°C here, and the gun shows around +22°C on a window above a
radiator, and +15°C on a window in a door.

I get the same reading on both coated and uncoated glass. The coated
class is very effective at shielding radiowaves.

Thomas

GregS wrote in message
...
In article
,
" wrote:
Do they work through glass? I would like to find a unit that will
allow me to check temperatures in vacant stores through the
storefront.

http://shop.vendio.com/BROADSTONEPRO.../?s=1231846607

Like this.

Thanks!

Peter Wieck
Melrose Park, PA

From experiance, its not going to work well. You will get some
relative indication of a general temperature of the inside comparing
different stores.

greg


As you can be shot and killed, quite legally with no retribution to them, by
the police in the UK just for carying a table leg or just looking Brazilian,
then not advisable to do such in the UK.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

" wrote in
:

On Jan 14, 5:21*pm, "William Sommerwerck"
wrote:
It's not a silly question.

Regular glass supposedly reflects infrared, does it not? And these
device
s
measure infrared, is not so?

Actually, glass reflects or absorbs infra-red based on angle and
composition and coatings (if any). Were it to reflect (all of) it, a
lens would not be very good at starting fires in by concentrating
sunlight.

Further, these guns use a laser and some sort of sensing device - so,
I am trying to determine how good it would be at sensing say... a wall
temperature a few feet inside a building through a window.

Peter Wieck
Melrose Park, PA

I would guess that the reading will be an AVERAGE of the actual wall
temperature and the glass temperature with weighing of those temperature
depending on the exact characteristics of the glass.

The only way to 'know' if it will work for YOUR application would be to
try it in enough cases. Measure the wall temperature directly (without the
glass in the path and then through the glass.

If you need to read the temp through the SAME glass, time after time, you
should be able to develop a calibration curve that will allow you to
accurately estimate the wall temperature.













--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

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