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Posted By: electure IR Thermometer - 01/06/02 03:26 PM
I'm going to buy an infrared thermometer today w/ the laser pointer.
Have you guys found these very useful? Kinda useful? Useless?
I'm just curious as to how prevalent their use is.
Anybody got any tricks or suggestions?
Posted By: Elzappr Re: IR Thermometer - 01/06/02 03:50 PM
We used an IR scope to find all sorts of trouble spots. Nice tool for drumming up work. It also could possibly save your life. I was on a job in an existing plant where a bus duct elbow fiting finally went phase-to-phase and blew up. That hot spot could have been discovered months before. Now, whenever I am in an area with lots of overhead bus duct, I spook myself wondering if any of the connections were installed wrong and a short might occur. I'd feel a lot safer if I could scope my work area for hot spots.
Posted By: Tom Re: IR Thermometer - 01/06/02 04:22 PM
How hot is too hot? Many of us run our hands over the breakers anytime we are dealing with a breaker box just to see if any of them are hot. The thermometer will tell you an exact temperature that you can make a judgement on instead of taking a SWAG.

Also great for checking motors that seem to be too hot. If you don't take a measurement, you don't know. After all, a 30 degree C rise above ambient is plenty toasty & you might think it is too hot since you'll barely be able to touch the motor.

Also, try finding the one ballast in an office that is about to go bad & is giving off that distinctive aroma. With the thermometer, you can narrow it down quite quickly.
Posted By: SPARKSALOT Re: IR Thermometer - 01/06/02 07:16 PM
For residential or light commercial use they really are not needed. For heavy commercial or industrial use they are indespensible. They are a fun toy......uh, I mean tool for any electrician however. I plan to buy one but to be honest I will mainly use it in my hobby, combat robots. Lots of things get hot in those.
Don
Posted By: sparky66wv Re: IR Thermometer - 01/06/02 08:51 PM
Com-Bots... Cool!

I'd like to get a couple of those LEGO Mindstorm kits and build simple Com-Bots with 'em...

An IR Thermometer would be a neat gadjet...
Posted By: SPARKSALOT Re: IR Thermometer - 01/06/02 11:31 PM
For sparky66wv------
Combat robots are lots of fun but they are terribly expensive. They also take up a bunch of time. How much time or money?. Every waking moment and all of you money. Believe me, you would be better off with several X-wifes than one robot. My lightweight cost several thousand dollars and hundreds if not thousands of hours of my time. But then, it has been more fun than my X,and is easier to get along with.
Don
Posted By: John Snell Re: IR Thermometer - 01/07/02 04:41 PM
IR thermometers can be great tools. A couple of cautions:
1. All of them have a specific Field of View (FOV) which is basically an indication of their ability to resolve a target of a specific size. For basic maintenance equipment you should have an FOV of at least 45 to 1. This means at 45" you can measure a 1" target, at 90" a 2" target, etc. Many of the low cost units ($100) have only a 6 to 1 FOV; this means you'll have to get VERY close to measure anything.

2. The laser aiming device should define the target size rather than being a single point. Most fully featured systems ($400-800) have a rotating laser circle that really works nicely.

3. You will not be able to measure temperatures of shiney, metal surfaces (or even oxidized ones), due to the fact that they do not emitt energy efficiently. You'll get a temperature, but it will not be accurate. EVEN if the device has an emissivity correction feature (and many of the higher end systems do), expect huge inaccuracies on unpainted metals.

4. It is very difficult to "scan" a large area with a spot radiometer. If you are looking at a limited number of specific connections or pieces of equipment, then they can be useful. Good used infrared IMAGING systems can be had for $2000-5000 which will do a much better job of scanning large quantities of equipment. There are now a number of new systems on the market in the undert $20000 range too.

5. How hot is too hot? Great question!!! Despite the fact that many people say they can predict failure based on surface temperature, it is NOT easy.

If you'd like more information on temperature measurement, I have a short checklist on "Improving infrared temperature measurement" that I would be happy to send you (and other readers) at not cost. Our company is the leading training company for thermography; we do not sell equipment but have great contacts with all imaging and spot radiometer manufacturers.
I hope this response, though lenghtly, is of help.
Thermally yours,
John Snell
Snell Infrared www.snellinfrared.com
Posted By: electure Re: IR Thermometer - 01/08/02 02:17 PM
John,
Thanks very much for the info...I think.
Looks like the one I've got should be used for testing the coffee pot, or maybe the hair on the neighbors dog's back. [Linked Image]
It's already helped me to find a hot connection on an energized xfrmr, and although not totally accurate, I'll still be able to make comparative tests. (About $100, 8-1 ratio,etc).
$20K is more than my company truck's worth!
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