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John Rumm John Rumm is offline
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Default Non-contact Infrared thermometer

On 09/08/2012 22:46, Tim Streater wrote:
In article ,
Dave wrote:

Tim Streater explained :
In article ,
Dave wrote:

Looking to buy an infrared thermometer without breaking the bank

and also without knowing exactly what I'm looking at - for
instance, what is "emissivity" and does it need to be adjustable?

Was there some reason you were unable to look it up?


Yes. I'm thick. Rather than read lots of confusing big words, I just
wanted someone to say yes, these are good little gadgets or no,
they're a waste of money. Or for someone to say, that's not a bad one
but this one is better.


:-)

John's explained about emissivity (but I still think you could have got
that info yourself). While he's right that a variable emissivity device
will be useful in more situations, generally you can take emissivity to
be 0.95, fixed, which is what the cheaper devices do. This covers most
surfaces except shiny ones, so you'll get a decent result off a rad
painted black or white, but not a shiny chrome one.


Worth noting that if you do want a reading of something metal and shiny,
then sticking a bit of tape on it will usually suffice to get a reading.


--
Cheers,

John.

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