Thermocouple terminal block errors 1

[KenAlmon]

Can anyone advise of what the error would be on a Type K thermocouple that is measuring flame temp on a flare tower where Type K extension leads are used all the way to the host comntroller located in the control room. At this point the extension leads go through a pair of ordinary SAK type terminal blocks. My intuition says that there is very little error (couple of degrees).

Any reference sites explaining the issues?

Thanks

Ken Almon

 

[xnuke]

As long as the temperature on each side of the terminal block is the same (which I'm sure that it is), the Law of Intermediate Materials applies. This basically says that the intermediate metal of the terminal block will produce no change in the emf in the circuit, as long as the temperatures at the two new junctions formed by the insertion of the intermediate metal are equal.

http://www.scanivalve.com/pdf/info_presstemphdbk.pdf

and

http://www.athenacontrols.com/pdf/catalog/RefInfo.pdf

xnuke

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