Thermocouple Calculator (NIST ITS-90)

Reference functions and inverse polynomials from NIST ITS-90 (SRD 60 / Monograph 175); the inverse is refined numerically so that t(E(t)) = t. Verified against every 10 °C point of the NIST tables. Tolerance classes of real sensors (IEC 60584-1) are not included.

Source: NIST ITS-90 Thermocouple Database (SRD 60), Version 3.0 — reference and inverse function coefficients