Linearized output to degrees celsius

[mitachky]

Hello,

I was wondering what would be the best way to convert my thermocouple reading into degrees celsius. I am using a UID-W1616R and a UIA-0402N. Right now I am using the Linearize function (X1 & Y1 = 0, X2 = 8191 and Y2 8191), which gives me a linearized output of 148 for 19.5 degrees C and 345 for 42 degrees C. And its a linear relationship. The problem I am facing for low temperature readings such as room temperature, is that the linearized output from my thermocouple varies by about +- 10. 

Any suggestions would be appreciated! 

P.S. I am a beginner in PLC programming

Thanks 

[Ausman]

If you have a thermocouple into the 0402N, I'm assuming you have sort of transducer involved.  What are it's specs?

cheers, Aus