Resistance to temperature conversion

[sujeep]

Hi,

I need to accept the resistance and convert that to temperature in Labview. Cn some one give me the formula.

Actualy I need to get the temperature below 73K. But my RTD (FP-RTD-122) has data configuration as 73k - 1123k and not below 73k.

So i hv to do this is the labview program by accepting the resistance (0-400 ohms) and convert to temperature.

Thanks in advance.

[Kenny_K]

What RTD device are you using?  That should get you started on what formula you need to use.

If the RTD has a range of 73 Kelvin to 1123 Kelvin, then you won't be able to measure under 73 Kelvin.  you will need a different RTD that can measure the range you are looking for.

[smercurio_fc]

Possible cross-post.

[sujeep]

Ok Sir, but cnt we get the resistance nd convert that to temperature. I wnt to knw hw 2 do that.

[Henrik_Volkers]

Something is wrong with your keypoard 😉

The manual of the FP-RTD-122 claims that you can measure resistance in the 0-400 or 0-4000 Ohms range. If the resistance of your sensor is in this range, just open MAX and configure the module

RTFM http://digital.ni.com/manuals.nsf/websearch/BF61417EFEE4EFCE86256CEE00691C9F

If you only have R=f(T) and need T=f(R) you can use

a lookup table (with linear or cubic interpolation ..)

the polynominal fit  (from the table above) to get a close approximation (higher order will result in an error less than 10mK, far less than the Sensor or 2 wire read)

 or Newton interation or.... or....  

Message Edited by Henrik Volkers on 06-28-2007 11:22 AM