According to an article in AutoSpeed.com, an Australian website for the Auto enthusiast, entitled:
Interesting Car Uses for an Infrared Thermometer Convenient and easy – but there are some traps
by Julian Edgar, the AutoSpeed website’s Editor, the main applications for automotive are:
* Brake temps to see if brakes are dragging and to determine their work share
* Engine sump temps to see if installing an undertray increases oil temps
* Temp drop across heat exchangers – engine oil cooler, trans oil cooler, intercooler, radiator
* Power steering fluid temp
* Tyre temps to see handling set-up
* Car sound amplifier temps”
Julian also points out, quite rightly, we believe:
“However, while there are some excellent applications for infrared temp measurement, there are also some major traps. For example, if you don’t know what you are doing, infrared temp measurement can have major errors. Like the 60 degrees C that you measure is actually 90 degrees…. Or vice versa.”
He then goes on to give a simplified explanation of “Emissivity”, apparently unaware of the correct term “Spectral Emissivity” as described (along with our perennial rant about why the term ‘Spectral” is key) in a recent article in our companion website SpectralEmissivity.com.
If you’ve seen our article you will realize that Julian also goes as far as to name one of the major instrument companies (who should know better) that tries to ‘dumb down’ Spectral Emissivity to just plain “Emissivity” or even the lower case version ‘emissivity“.
(At least he and they spelled it correctly.)
Why, you might ask, is spectral emissivity the correct term?
It is a rather long story covered expertly, we think on our original website, About Temperature Sensors, in a section called The Emissivity Trail or E-Trail.
Some people will try to justify a single emissivity value as adequate and accept that spectral, while technically correct, makes it a lot harder for users to understand, buy and use infrared thermometers. (It make the selling job easier and the whitewash given spectral emissivity is the lazy marketing person’s way to better sales, in our opinion).
What it actually does, again in our opinion, is continue user and salesman’s ignorance.
The justification for the pages on emissivity on About Temperature Sensors was attending a class on infrared thermometers and applications put on by a major USA maker of the devices. It was an informative class except for the part on emissivity.
The instructor, a long time sales manager for the company, confused every student in the room with a jumbled, rambling description of what emissivity was and how a user can properly correct for it in actual real-world measurement conditions. He was obvious that he didn’t know what emissivity was and he was able only to transfer his ignorance of the subject to the students.
It is about time, we think, that those who are in the business of making and selling these exceptional devices wake up and start doing things correctly. It’s not terribly hard and the concepts are not very difficult to understand. But, they sure are easy to misunderstand and mangle.
Visit SpectralEmissivity.com regularly longer and soon you’ll see a series of brief tutorials on what Spectral Emissivity is and how one can effectively use knowledge of it in making quality temperature measurements.
Until then, we think your best bet is to set the emissivity correction to 1.0 and use what is more precisely called “Spectral Radiance Temperature”.
More on that new term later, too. That will be here in our own glossary of terms.
Anyone want to help us start it?
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