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RTD Tolerances, Classes and Comparisons

Platinum RTD Tolerance Values

Temperature °C Resistance Value Ω Tolerance DIN-IEC-751
Class A
°C (Ω)
Class B
°C (Ω)
-200
-100
0
100
200
18.52
60.26
100.00
138.51
175.86
±0.55-(±0.24)
±0.35-(±0.14)
±0.15-(±0.06)
±0.35-(±0.13)
±0.55-(±0.20)
±1.3-(±0.56)
±0.8-(±0.32)
±0.3-(±0.12)
±0.8-(±0.30)
±1.3-(±0.48)
300
400
500
600
650
212.05
247.09
280.98
313.71
329.64
±0.75-(±0.27)
±0.95-(±0.33)
±1.15-(±0.38)
±1.35-(±0.43)
±1.45-(±0.46)
±1.8-(±0.64)
±2.3-(±0.79)
±2.8-(±0.93)
±3.3-(±1.06)
±3.6-(±1.13)

RTD Tolerance Class Definitions

DIN class A: ± [ (0.15 + 0.002 | t | ] °C 
DIN class B: ± [ (0.30 + 0.005 | t | ] °C


RTD Resistance Wire Comparisons

Element Metal Temperature Range Benefits Base Resistance TCR (Ω/Ω/°C)
Platinum -260 to 850°C
(-436 to 1562°F)
Best stability, good linearity 100 Ω at 0°C 0.00385 (DIN-IEC-761), 0.003916 (JIS 1604-1981)
Copper -100 to 260°C
(-148 to 500°F)
Best linearity 10 Ω at 25°C 0.00427
Nickel -100 to 260°C
(-148 to 500°F)
Low cost, High Sensitivity 120 Ω at 0° C 0.00672