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Topic: Using thermocouples (5 msgs / 124 lines)
1) From: Kevin DuPre
Given that thermocouples are inherently non-linear
(I've designed instrumentation with them and had to
use a thermocouple compensation amplifier chip to get
a correct reading), what do all of you using
thermocouples do to interface to a digital voltmeter,
or analog meter if that's what you use?
=====
--
Kevin DuPre
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2) From: Dan Bollinger
The DVM I use has a special plug for the TC, those standard little flat
blades, and must always use the same TC.  They must have the chip built in.
Dan
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3) From: Jim Schulman
Certain Fluke and Omega multimeter models have one or two k type TC inputs with the 
linearization circuits included. The most expensive ones can be calibrated and used for 
other TC types. 
The low end, dual k-type Omega model I use ran about $100. It uses a proprietary plug for 
the TCs. Two naked TCs, with 800C fiber-glass insulation were included, extra ones cost $5 
to $50, depending on how exotic you want the probe and insulation to be. 
My only gripe with it is that the two probes short out if one is measuring two spots with a 
conductor in between. For instance, measuring the beef's center and the braising liquid at 
the same time is a no-no. Otherwise, it's best all round cooking thermometer there is.
On 19 Sep 2002 at 13:14, Kevin DuPre wrote:
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4) From: floyd burton
Jim-what is the model # of a good Fluke-one that I could use to download
time series temps into a laptop.  Gotta buy a Fluke for another product to
measure conductivity-why not spend a few more bucks and get one that will
measure temps in a series.
thanks

5) From: Jim Schulman
Hi Floyd,
There's some $150 multimeters with rs-232 inputs (serial port) here:http://www.omega.com/ppt/pptsc.asp?refM10_20_30&Nav=j06
Unfortunately, none seem to have both rs-232 and temperature input. Email them for tips. 
Afaik, you can use them for single channel applications if you do the linearization in 
software, or alternatively, use $100 precalibrated 4 - 20 ma transmitters on the TCs, the 
omega versions are here:http://www.omega.com/vh/subsectionvh.html?subsectioną1&book=vhtmJim">http://www.omega.com/toc_asp/subsectionSC.asp?subsection3&book=TemperatureThen there's some $1500 + multi-channel PC data acquisition systems here:http://www.omega.com/vh/subsectionvh.html?subsectioną1&book=vhtmJim
On 19 Sep 2002 at 15:41, floyd burton wrote:
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