I just got an infraed thermometer

[xrunner]

No it's not a mistake, I really received a new infraed thermometer.

[kalel]

Have fun with the new meter. I wouldn't really mind typos from the products as long as the price is right.

[frozenfrogz]

infra - prefix; meaning: below, lower, "underlying"

Infraed (abreviation for infra-education) therefore translates to either lower / basic education OR learning of underlying principles.


So it is a thermometer that will teach you about the underlying principles in science and nature!

Congrats and have fun with it I have a Testo 830-T2 and it comes in very handy once in a while!

[xrunner]

I just got it to find hot or cold spots around the house. They were so cheap ($11) I ordered two so I could give my neighbor one. It works fine. The funny thing is that the manual shows a picture of the unit and the same label and it's spelled correctly. 

[frozenfrogz]

The funny thing is that the manual shows a picture of the unit and the same label and it's spelled correctly. 

Sounds like a case for Dirk Gently’s Holistic Detective Agency 

[RoGeorge]

That label must have been written by a wabbit. 

[Red Squirrel]

I was trying to figure out what's wrong with this, did not even notice the typo at first.     lol

I accidentally triggered the calibration feature on a cheap Mastercraft one and put it out of cal and I could not figure out how the cal feature actually worked so that I can fix it.  I think it required me to point it at several surfaces of specific temp, and I had no way of producing that.   Opened it up and it was a COB so GL trying to figure out any details, and I also could not get it back together, so bought another.  I kept the old one, the sensor itself may possibly come in handy at some point for something.  Custom heat or fire detector maybe?  Or maybe motion detector?

[Decoman]

I have an el cheapo IR thermometer and I only learned today that the temperature readings in my case, doesn't seem to be proper where the laser is pointing, and it doesn't seem like my el cheapo meter works properly, as there is no indication of the laser having anything other than a simple dot of focus, at ANY distance. I expected a variable dot size reading off the packaging.

Anyway, I learned today that the laser is ofc situated above the temp sensor (I think) and so, I have to remember to aim a little higher at what I am supposed to measure the temperature off.

Fun things: Measuring the temperature inside my fridge and refrigerator. And I noticed that the temp in the refrigerator was a little too high (6-7 deg C), so I made an adjustment to the knob inside the refrigerator, presumably, it should become more cool inside the refrigerator from now on.

I tried measuring the temperature of the flame off a small blow torch, but the reading only showed about 100 deg C which seemed odd, though I am not expert. Looking at the specs for a similar product on eBay, it looks like there is a limit of 500 deg C, so I guess maybe the flame was actually hotter than 500 deg C, unsure.

[xrunner]

I tried measuring the temperature of the flame off a small blow torch, but the reading only showed about 100 deg C which seemed odd, though I am not expert. Looking at the specs for a similar product on eBay, it looks like there is a limit of 500 deg C, so I guess maybe the flame was actually hotter than 500 deg C, unsure.

It may be due to emissivity issues. Different materials have different emissivties -

http://www.thermoworks.com/emissivity_table

(black body = 100%)

If you measure the tip of your soldering iron with it, it won't measure correctly, because the metal has a low emissivity. You have to use a thermocouple. I know my tip temp because I have a Hakko FG-100 tip thermometer. But when I try to read it with the infraed infrared thermometer it reads more than 100 C lower. It's the emissivity issue. I don't know what the emissivity of a flame is - check the internets ... 

[nctnico]

When using these kind of contactless thermometers you can only measure accurately on black matte materials otherwise you get large errors. A piece of masking tape made black with a thick velt pen already helps.
I've attached a picture of a big rectangular heatsink with 5 pieces of black tape stuck on it. The temperature reading is way off at the areas which are bare aluminium.

[ChrisLX200]

When using these kind of contactless thermometers you can only measure accurately on black matte materials otherwise you get large errors. A piece of masking tape made black with a thick velt pen already helps.
I've attached a picture of a big rectangular heatsink with 5 pieces of black tape stuck on it. The temperature reading is way off at the areas which are bare aluminium.

Not really true - you chose the worst case with aluminium though where emission is down to about 30%. Most other materials are up around 90-95%. My IR thermometer has the ability to define the material you are pointing at. I've reproduced the list of emmisivities below copied from the RayTek manual..

[glarsson]

Not really true - you chose the worst case with aluminium though where emission is down to about 30%. Most other materials are up around 90-95%. My IR thermometer has the ability to define the material you are pointing at. I've reproduced the list of emmisivities below copied from the RayTek manual..

Take note of the footnotes in the RayTek list. Take stainless as an example. We like to keep stainless polished, not oxidized, so it will be highly reflective and the IR thermometer will then show the temperature of whatever is reflected by the steel, not the steel itself.

[Red Squirrel]

These thermometers measure an area and not a single spot, so the laser is a bit misleading.  I do wonder if they make some that measure a given spot though, that would be handy.  The further you are from the test subject the larger area it's measuring.

[xrunner]

I gave my neighbor the other one this morning. He was not aware of such things. After I showed him what it could do he was all over the house with it measuring temps! 

[Red Squirrel]

Hahaha that was me the first time I got myself one of those.

But it's not enough, I want a FLIR now.  Must resist spending money just so I can see how terribly insulated my house is. 

[Tadas]

I gave my neighbor the other one this morning. He was not aware of such things. After I showed him what it could do he was all over the house with it measuring temps! 

Does your neighbour have a cat?

[frozenfrogz]

These thermometers measure an area and not a single spot, so the laser is a bit misleading.  I do wonder if they make some that measure a given spot though, that would be handy.  The further you are from the test subject the larger area it's measuring.

At least for the ones built for industrial applications, there is always information on the measurement area at a given distance and you can (and usually need to) set the emissivity factor according to what surface you are going to measure.

The attached screenshot is from the Testo 830 product brochure.
T1 model has one laser pointing to the middle of the measuring area, 10:1 optics
T2 model has two lasers pointing to the upper and lower boundary of the measuring area, 12:1 optics
T4 model has also two lasers as T2 model but with 30:1 optics
All specs are in here. Other manufacturers are doing it likewise.

For the correction through emissivity factor you can use the values from a table or (usually done in industrial applications) use special stickers or coating materials with high emissivity and low reflectivity. This article is a comprehensive starting point.

Keep in mind though, that these IR thermometers with wide temperature range are mainly used for checking approximate values i.e. check if a motor or circuit breaker is running hot - in these applications the absolute values do not matter much OR they are calibrated for one special purpose. There are some specialized thermometers for health and food inspection that have a much narrower working temperature range. These are used for inspection and quality control including temperature logs and paper work. However, there will usually also be an additional thermocouple probe for checking core temperatures etc.

[xrunner]

Does your neighbour have a cat?

LOL - no but I do, I will measure her tomorrow.

BTW welcome to the forum. 

[Mr. Scram]

Does your neighbour have a cat?

That's obviously not going to work. You need a infrapet thermometer for that.

[Red Squirrel]

It's actually incredible how much heat cats put off lol.  I've measured mine too.   

[beanflying]

I have had a cheapy one for a while as my local 'health inspector' suggested I 'needed one' to test food products I was preparing and selling. The guy is a first class Banker 

Same thing as below goes for his several hundred dollar 'calibrated' one 

Doesn't work on shiny or reflective products. Reads incorrect on milk in a bottle for example and chromed surfaces forget about it.

Works great on a lot of darker coloured liquids including oils, syrups, curries etc.

The same Banker tried to instruct me that I should also use it when cooking fried eggs to make sure they were cooked through. Banker has no clue on IR as they read only surface temperature and a recently flipped egg will be a lot higher than the core. So what does this have to do with electronics, before you take IR readings as gospel understand they are not core or die temperatures in IC's and unless the DUT has been on for a decent period won't be correct and some shiny cases and heatsinks may be out in results.

For testing Cat temps I always thought that is why the lifted their tails 

[Mr. Scram]

It's actually incredible how much heat cats put off lol.  I've measured mine too.   

Quick, to the patent office!

[Rick Law]

It's actually incredible how much heat cats put off lol.  I've measured mine too.   

Quick, to the patent office!

Actually, another good use is as a zombie detector.  Since they are dead, they should be operating at room temperature.  Now you can tell from a distance if they are one that eats you, or one that will just say "HI" and move on.

Make sure you use a rechargeable version.  Catch a bunch of zombies, tie them to a big wheel like like river driven mill but let it drive a generator.  Zombie doesn't need a pumping heart to walk, so that implies their cells don't need food to operate.  They can recharge your thermometer and power your house until their legs rot away.

With a bit of good electronics, it just make a post-apocalyptic world easier and safer to live in.

[Brumby]

[xrunner]

I call this - cat taking sunbath in window.