Does this really work?

[TheNiceGuy]

http://www.thinkgeek.com/gadgets/electronic/5d95/

I wanna know what the "+/- 2%" error means.

 

[f95toli]

Looks like a simple pyrometer so yes, it should work.

+-2% means is the error.
It means that if the device indicated 10 degress the true results is within 10+-2%, i.e. the range 9.98 - 10.02 degress

 

[PottedMeat]

Seems like a pretty common error value for contactless thermometers:

this Jameco.com Extech Pocket IR Thermometer ( $59.99 ) one says:

Accuracy: ±2.5% of reading + 3°F/2°C

Some technical info on how they work: Melexis Infrared Thermometer Module

 

[TheNiceGuy]

thx.
Are there any issues/limitations with it?
could I fire this at a mountain top or something miles away and get an accurate temp.?

 

[PottedMeat]

Heh, nope you cant measure the temperature of something miles away - According to the manual, the one I linked above has a 6:1 distance to measured region size ratio. So if you hold the sensor 6" from the target, it will give you the average temperature in a region 1" in diameter. So holding it 36" ( 3 Feet ) from a target will give you the average in a 6" diameter circle. I guess it may work pointing it to a far away location, but you'll only get the average temp in a huge area.

Manual: http://www.extech.com/instrument/products/alpha/manuals/IR201_UM.pdf

 

[TheNiceGuy]

Thank you!

 

[Bassyhead]

Yes, they're pretty common and they do work. Like PottedMeat said, the farther away the surface you measure is, the larger the area that is measured.

 

[xanis]

The +/- 2% error means that the temperature reading will be accurate with a 2% error margin, which is pretty accurate.

 

[V00D00]

They are designed for testing the temp of things that are really hot and in tight places. Not for getting the temps from the top of a mounntain. I suppose if you were to focus the beam, and if it can go long range, then yes, you theoretically could do that.

 

[Mday]

Originally posted by: TheNiceGuy
http://www.thinkgeek.com/gadgets/electronic/5d95/

I wanna know what the "+/- 2%" error means.

They work fairly well and can be calibrated for various environments. The error produced varies with the distance, most of what you see are calibrated for readings in air.

+/- 2% means, if you get a reading of 100 degrees, the actual temperature can vary from 98 to 102 degrees. A 2% error is pretty high imo.

 

[Shalmanese]

Wait, how does it make sense to say it has a +-2% in any scale but Kelvin?

 

[The Boston Dangler]

It's an infrared thermometer. Laser sight, 8:1 spot size, 500F, $99. That's what you want.

Did any one look at the last pic? He's pointing it into the AC vent of a car, and it says 95.

 

[CycloWizard]

Originally posted by: The Boston Dangler
It's an infrared thermometer. Laser sight, 8:1 spot size, 500F, $99. That's what you want.

Did any one look at the last pic? He's pointing it into the AC vent of a car, and it says 95.

Uh, maybe the heat's on? In any case, I'm not real impressed that they Photochopped in a laser beam... That just makes it look even more ghetto.