v1.0 (AI Audited, 29/7/2025). Confirm suitability before use.
About RTD Tolerance Classes
IEC 60751 defines tolerance classes for industrial platinum resistance thermometers. Each class specifies maximum permissible deviations from the standard resistance-temperature relationship. This calculator determines which tolerance class (if any) a sensor meets based on a single temperature and resistance measurement.
Measurement Input
Results
IEC 60751 Tolerance Classes
| Class | Tolerance Formula | Temperature Range |
|---|---|---|
| Class AA | ±(0.1 + 0.0017|t|) °C | -50°C to +250°C |
| Class A | ±(0.15 + 0.002|t|) °C | -100°C to +450°C |
| Class B | ±(0.3 + 0.005|t|) °C | -196°C to +600°C |
| Class C | ±(0.6 + 0.01|t|) °C | -196°C to +600°C |
Notes
- |t| represents the absolute value of temperature in °C
- Temperature ranges are for wire-wound elements
- Thin-film elements have more restricted ranges
- Class AA was formerly known as 1/3 Class B
- Class C was formerly known as 2 Class B