NOTE: The values on the Platinum 385 curve are based upon either the ITS-90 or IPTS 68 temperature scale. Older instrumentation may still be using IPTS68 values to convert resistance into a temperature value.
Refer to your instrument technical manual to determine if it is programmed to the old or current temperature scale.
Note: IEC added 0.00385055ºC to the formula. This accounts for the change between ITS-90 and IPTS68 which becomes noticeable as follows;
100ºC = 0.0269ºC, 200ºC = 0.0565ºC, 300ºC = 0.0891ºC 400ºC = 0.1540ºC, 500ºC = 0.2547ºC, 600ºC = 0.3638ºC
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