-200 °C − 0 °C:
$$R_t = R_0 [1 + At + Bt^2 + Ct^3 (t-100)]$$
0 °C − 850 °C:
$$R_t = R_0 [1 + At + Bt^2]$$
$A = 3.9083 × 10^{-3}$ °C-1
$B = -5.775 × 10^-7$ °C-2
$C = -4.183 × 10^-12$ °C-4
$α = (R_100 - R_0) = 0.00385055$ °C
PT1000 = PT100 × 10
PT500 = PT100 × 5