Tony Olsen on sat 2 aug 03
------------------------------------------------
That is, I print out the document, buy the multimeter from Radio Shack =
and plug in/ connect my new thermocouple off of old analog pyrometer and =
I can use the chart to tell me the temperature ?? That sounds too =
straightforward, so I suspect I have missed something.
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MarjB,
Yes, it is a bit more complicated than that. A "Junction" will be =
formed at your meter when you plug in the TC (thermocouple.) This =
junction will introduce an error roughly proportional to the temperature =
of the connection at the meter. There is a device known as a cold =
junction compensator that can be plugged in to correct this error.
Here's a bit of theory on TC measuring:
http://www.omega.com/techref/thermoref.html
Some actual cold junction devices:
http://www.ectron.com/prods/tcmate.htm
http://www.isotechna.com/Files/40/FROSTY.pdf
Here's a TC meter I bought on ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=3D4678&item=3D2535=
248024
There are cheaper ones out there, but be sure that it covers the range =
you need and will accept the TC type you are using.
Hope this helps..
Tony Olsen, (Galveston TX)
neslot@houston.rr.com
http://tonyolsen.com/up/
MarjB on sat 2 aug 03
Morning Steve Harrison
I did a quick "google search" and this site (below), appears to provide =
the charts you referred to: Millivolts to temperature conversions.
Please have a look and tell me if I am on the right track. That is, I =
print out the document, buy the multimeter from Radio Shack and plug in/ =
connect my new thermocouple off of old analog pyrometer and I can use =
the chart to tell me the temperature ?? That sounds too =
straightforward, so I suspect I have missed something.
Thank you. MarjB
www.rosemount.com/document/tds/3061b00Q.pdf
steve harrison on sun 3 aug 03
Hi Marg B
Yes it is that simple,
the only complication is that it doesn't allow for room temperature,
you have to add that on for accuracy.
but most potters who use this system also use cones, so just use the
t/c as a guide.
regards
Steve Harrison
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