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I need Type C thermocouple signal conditioning, or a VI that has the reference table employed.

14 years later and there is almost no information anywhere about C-type thermocouples, so I did similar to what Sue did. 

1. I used https://arachnoid.com/polysolve/ to get a curve fit of data from https://www.pyromation.com/Downloads/data/emfc_c.pdf 

2. Using the NI-9211 module in a NI-9147 Ethernet CompactRio Chassis 

3. Started with the NI 9211 Getting Started.lvproj project file, it's the example provided by NI (had to move some files around with assistance from David and Kevin in NI technical support)

4. Added a new case for C-type thermocouples in both the Temperature to Volts.vi and Volts to Temperature.vi files using both of the curve fit formulas below.

5. Added C type as an option in all of the necessary front panels by right clicking -> properties -> edit items -> add C in the correct position

6. It should work now! Skipping a bunch of steps, it took me a lot longer than I'm making it sound.

 

V= pow(c,0) * -2.8508982068349564E-4 +
pow(c,1) * 1.3399269198668894E-2 +
pow(c,2) * 1.2214353922012759E-5 +
pow(c,3) * -1.0439621409504520E-8 +
pow(c,4) * 3.5767945903631794E-12 +
pow(c,5) * -4.9058085554296805E-16;

 

T= pow(v,0) * (1.0296628317468555E0) +
pow(v,1) * (7.0605666587756133E1) -
pow(v,2) * (2.4379417766489446E0) +
pow(v,3) * (1.3615720688375876E-1) -
pow(v,4) * (3.4276988567046060E-3) +
pow(v,5) * (3.6848981973459947E-5);

 

Here's the data to plug into the curve fit tool to save you time (it does both forward and inverse curve fits, and is very accurate all the way from 0 to 2300 C):

0 0
10 .135
50 .699
100 1.451
150 2.251
200 3.090
250 3.963
300 4.865
350 5.789
400 6.732
450 7.689
500 8.657
550 9.631
600 10.609
650 11.585
700 12.559
750 13.529
800 14.494
850 15.451
900 16.398
950 17.335
1000 18.260
1050 19.172
1100 20.071
1150 20.955
1200 21.825
1250 22.680
1300 23.520
1350 24.345
1400 25.155
1450 25.949
1500 26.729
1550 27.493
1600 28.243
1650 28.977
1700 29.696
1750 30.399
1800 31.087
1850 31.758
1900 32.413
1950 33.050
2000 33.669
2050 34.269
2100 34.849
2150 35.406
2200 35.940
2250 36.449
2300 36.931

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Hi nateweger,

 

instead of supplying all that text you could have supplied some VIs instead…

 

Calculating coefficients from your data:

Best regards,
GerdW


using LV2020 on Win8.1+cRIO
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