Thermocouple reading

Hi,
I am working with a type K thermocouple and I use a LM 35 temperature sensor to get an accurate CJC. I have got an external serial device were I do the voltage measurement of both (K and LM35), that means I get the voltage value as string using VISA in Labview.
I would like to use the thermocouple reading vi for the linearization. My questions are:
Which option should I choose on the CJC sensor input of the thermocouple reading vi?
Can I connect the value that I get from the lm 35 to the CJC voltage input of the thermocouple vi?
Thanks

Hi Navarro,
thank you for your answer.
The first thing you have to define, is the Temperature Unit you want to get as the output of the Converter VI. Please refer to the LabVIEW help for the options:
Convert Thermocouple Reading VI - LabVIEW 2014 Help - National Instruments
http://zone.ni.com/reference/en-XX/help/371361L-01/lvinstio/conv_thermcoup_read/
As you described, your serial device returns scalar singular values to you, choose the scalar option of the converter VI.
The CJC options depend on your reference sensor. You can use a voltage or current reference, depending on what signal comes from the reference. Please refer to the help and the following link for more information:
What is CJC and Why Does My Data Acquisition Board or Signal Conditioning Unit Include a CJC Sensor? - National Instruments
http://digital.ni.com/public.nsf/allkb/E332E1D829059FB5862570AE005066B3
I hope, this helps.
Best regards,
Melanie

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bkb wrote:
So AI0 is the CJC value? And I have to specify CJC Channel when I read the TC? Why is it that I got this to work when specifying Built-In source, and wired the thermocouple to AI15? And why does it not work on other channels?
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Message Edited by Otis [DE] on 01-13-2006 11:37 AM
Message Edited by Otis [DE] on 01-13-2006 11:38 AM
Otis
Training and Certification
Product Support Engineer
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How to measure thermocouple in lab view and save the data..

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