How does it work?

[Tikiman]

I purchased a Klein infrared temperature measuring device for my Ooni pizza maker recently. You point it at a surface, squeeze the trigger, and it tells you the temperature of the surface. I have been trying it out on various surfaces like my granite countertops, the top of my woodburning stove (which maxed it out at being over 760 degrees), and other things.

My question is, how does the ****ing thing work? Anyone know?

[Torqaholic]

Infrared is a light wave. The hotter the brighter. It's basically taking a picture of the surface and comparing it to a color chart.

[Frankie the Fink]

Infrared is a light wave. The hotter the brighter. It's basically taking a picture of the surface and comparing it to a color chart.
As good an explanation as any, but then I still can't figure out how the original Etch-A-Sketch worked.

[Burro (He/Haw)]

We use those things at work to see if steam traps are blowing by. They also used them at work when Covid was at its peak to check your temperature. (Not kidding)

[Tikiman]

Infrared is a light wave. The hotter the brighter. It's basically taking a picture of the surface and comparing it to a color chart.

It doesn't seem to matter what the surface is. From rough cast iron, to smooth granite, to boiling oil. It just knows the temperature of the surface. Pretty amazing for something that costs less than $60.

[Mike Mercury]

https://i.pinimg.com/originals/97/ed/76/97ed766defe98982fe31a6126bb858e9.jpg

[Aerovette]

It doesn't seem to matter what the surface is. From rough cast iron, to smooth granite, to boiling oil. It just knows the temperature of the surface. Pretty amazing for something that costs less than $60.

Distance impacts the reading. I know this from using mine.

[Tikiman]

Distance impacts the reading. I know this from using mine.

Good to know. :yesnod: I've been using mine anywhere from 6" to 12" without any noticeable difference of temperature readings, but I imagine there is a limit to what it can do.

[Aerovette]

Good to know. :yesnod: I've been using mine anywhere from 6" to 12" without any noticeable difference of temperature readings, but I imagine there is a limit to what it can do.

You won't see any variation at those distances. I was aiming at AC vents measuring air exiting the vent. At 10 or 15 feet, it was reading warmer than at 1 or 2 feet. I found the same when using it for my grill and an engine.

[Yadkin]

My dad, a retired electrical engineer, had very little patience answering questions as how stuff worked. If an explanation took anything more than say, 20 seconds, he'd say "it's magic".

Those are indispensable diagnostic tools. Sample individual tubes on an exhaust header to determine if a cylinder isn't working as hard as the others. Brake discs to see if one is dragging, or not working as it should. Cooling/ heating circuits.

[Burro (He/Haw)]

My dad, a retired electrical engineer,
Of course he was.

:funniest:

[GTOguy]

My dad, a retired electrical engineer, had very little patience answering questions as how stuff worked. If an explanation took anything more than say, 20 seconds, he'd say "it's magic".

Those are indispensable diagnostic tools. Sample individual tubes on an exhaust header to determine if a cylinder isn't working as hard as the others. Brake discs to see if one is dragging, or not working as it should. Cooling/ heating circuits.

That explains a LOT about your personality. :seasix:

[Burro (He/Haw)]

That explains a LOT about your personality. :seasix:

There’s a significant difference between won’t explain and can’t. You know - dumb.

[DJ_Critterus]

Of course he was.

:funniest:

He was only off by 1/8th of an Ohm.... :leaving:

[Torqaholic]

... If an explanation took anything more than say, 20 seconds, he'd say "it's magic".

...

I considered it :rofl:

[Yadkin]

There’s a significant difference between won’t explain and can’t. You know - dumb.

Are you so desperate for attention that you're attacking my dad now? :spdchk:

[Yadkin]

I considered it :rofl:

Back in the early 90's I built a very large steel-framed building, corrugated steel roof, mostly open sides for a drying process that I was providing QA/QC for. It was bolted directly to H-piles, set in a grid 130' x 30' and an average depth of 260 feet. The city inspector insisted that I install lighting protection.

I had hired my dad to do the electrical design for the job. He laughed at the request, how stupid it was. But I had to toss the inspector (Barney Fife) a bone. So dad specified some weird contraption that he had used many times in the past. I asked him how it worked. "Magic."

I presented the spec to the inspector, and he asked me how it worked. I gave him my dad's answer.

Fife made me install dumb little lightning rods along the roof ridge. These we wired down to 1/2" x 10' copper clad rods driven right next to the huge H piles. Total waste of time/ money. :Jeff '79:

[Burro (He/Haw)]

Are you so desperate for attention that you're attacking my dad now? :spdchk:

I know this’ll take a level of attention you’re not accustomed to but pay attention mope;

The can’t is you.

[Mick]

We use those things at work to see if steam traps are blowing by. They also used them at work when Covid was at its peak to check your temperature. (Not kidding)

One thing most people "know" but never really think about is that you can't see water vapor in air, it is completely invisible. That is why even though there is pretty much always some water vapor in the air around you (humidity), you can't see the air. Let the air drop below the "dew point", and you get fog, which is condensed water vapor.

Back in ancient times when I was a young engineer, we didn't have fancy infra-red detectors like that. If we sprung a high pressure steam leak, you could hear it, but could not see it because it was so hot, it stayed as vapor until it cooled down. So we would hear a steam leak, and the outer portions of the building were fogging up as the steam condensed, buy you couldn't see exactly where the leak was. The common method to finding it is a guy would walk around with a broom stick, and when he saw the end of the stick disappear (because the live steam had sheared it off), that's where the leak was.

Thankfully, in my job, I never had to be the "broomstick guy".

[Yadkin]

That explains a LOT about your personality. :seasix:

Y

[Yadkin]

I know this’ll take a level of attention you’re not accustomed to but pay attention mope;

The can’t is you.

Yeah sure. :spdchk:

[ZipZap]

Good to know. :yesnod: I've been using mine anywhere from 6" to 12" without any noticeable difference of temperature readings, but I imagine there is a limit to what it can do.

You asked for it...

Actually did some design work for IR cameras back in the day.

First, the laser is just a pointer and has nothing to do with the sensor.

IR energy is produced at wavelengths just below the visible spectrum (sorry, no discussion on quantum, so I'm sticking to waves). It can be focused with silicon lenses just like visible RF. The IR spectrum is actually divided into two somewhat distinct regions, near and far. We "feel" the near IR, which is closest to visible. There are some interesting things about far IR, but I won't digress. Your tool measures in the near IR range. Once focused through a lens, the energy impinges typically on a "thermopile". Why thermopile? It is literally a pile of thermocouples, similar to the bi-metal thermocouples that you have as a flame sensor in your NG HVAC. A pile is needed to amplify the small amount of IR energy into a useful signal. The energy is measured against a reference inside the unit in a thermally stable block. The delta-T creates electricity in proportion to the delta, and is measured by electronic circuitry and processed into the display as "absolute" temperature. As far as distance from target, the lens used has a field-of-view. If the target is smaller than the FOV, then the sensor is seeing area around the target along with the target. Good sensors actually publish the FOV in the form of "Distance to Spot" ratio. It specifies how far away from the target the sensor can be to obtain an accurate reading. If the D/S is 10, a 2" diameter object needs to be read at less than 20" (10:1 x 2). Your pizza stone probably easily fills the FOV of your sensor at 12". Shooting duct work from 15 or 20 feet becomes much more problematic.

[Aerovette]

I have a black truck and have used it to measure the surface temperature on a hot summer day.

[Burro (He/Haw)]

One thing most people "know" but never really think about is that you can't see water vapor in air, it is completely invisible. That is why even though there is pretty much always some water vapor in the air around you (humidity), you can't see the air. Let the air drop below the "dew point", and you get fog, which is condensed water vapor.

Back in ancient times when I was a young engineer, we didn't have fancy infra-red detectors like that. If we sprung a high pressure steam leak, you could hear it, but could not see it because it was so hot, it stayed as vapor until it cooled down. So we would hear a steam leak, and the outer portions of the building were fogging up as the steam condensed, buy you couldn't see exactly where the leak was. The common method to finding it is a guy would walk around with a broom stick, and when he saw the end of the stick disappear (because the live steam had sheared it off), that's where the leak was.

Thankfully, in my job, I never had to be the "broomstick guy".
40 year Steamfitter. I'm familiar believe me.

[Tikiman]

You asked for it...

Actually did some design work for IR cameras back in the day.

First, the laser is just a pointer and has nothing to do with the sensor.

IR energy is produced at wavelengths just below the visible spectrum (sorry, no discussion on quantum, so I'm sticking to waves). It can be focused with silicon lenses just like visible RF. The IR spectrum is actually divided into two somewhat distinct regions, near and far. We "feel" the near IR, which is closest to visible. There are some interesting things about far IR, but I won't digress. Your tool measures in the near IR range. Once focused through a lens, the energy impinges typically on a "thermopile". Why thermopile? It is literally a pile of thermocouples, similar to the bi-metal thermocouples that you have as a flame sensor in your NG HVAC. A pile is needed to amplify the small amount of IR energy into a useful signal. The energy is measured against a reference inside the unit in a thermally stable block. The delta-T creates electricity in proportion to the delta, and is measured by electronic circuitry and processed into the display as "absolute" temperature. As far as distance from target, the lens used has a field-of-view. If the target is smaller than the FOV, then the sensor is seeing area around the target along with the target. Good sensors actually publish the FOV in the form of "Distance to Spot" ratio. It specifies how far away from the target the sensor can be to obtain an accurate reading. If the D/S is 10, a 2" area object needs to be read at less than 20" (10:1 x 2). Your pizza stone probably easily fills the FOV of your sensor at 12". Shooting duct work from 15 or 20 feet becomes much more problematic.


Thank you. :cheers:

[Mick]

40 year Steamfitter. I'm familiar believe me.

:thumbs:

I got the feeling OSHA wasn't real thrilled with the practice. :yesnod:

[Burro (He/Haw)]

:thumbs:

I got the feeling OSHA wasn't real thrilled with the practice. :yesnod:

I never actually saw that being done but I've heard of it.

I've done some actual steam blows starting up boilers. All kinds of shit get's left inside pipe. Weld rod stubs, files, gloves, you name it. When they did the steam blow at Sherco 3 it was so loud the local cows stopped producing milk. :Jeff '79:

Sherco 3 is a BIG MoFo coal fire. 900 MW.