Thread: RTDs suck!
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Unread 07-20-2004, 08:14 PM   #1
bigben2k
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Join Date: May 2002
Location: Texas, U.S.A.
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RTDs suck!

RTDs suck!

I was set on using RTDs for my testbench, and I'm finding out that thermocouples would be more appropriate, for a number of reasons:

1-the response slope of an RTD is almost flat, making it virtually impossible to detect temperatures with a resolution of 0.01 or smaller. Thermocouples have a nice slope, but it's not quite linear. Omega does however carry "linear response" TCs...

2-Going over Omega.com 's PRTD elements, class A or class B, the response time is really poor, compared to thermocouples.

PRTDs have an advantage where their linearity varies very little, over a very wide temperature range. Useless to me, I'll be measuring temps within a very narrow range, and response time is actually important!!!

I might get one PRTD, but just for the sake of getting an accurate reference point, checking temps alongside thermocouples. BTW, a class A PRTD has an accuracy of +/- 0.15 deg C (element alone, not counting the temp reader).


Anyone want links to the PRTD info from Omega?
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