11.4 Measuring tolerances for resistance thermometers
Tolerance classes
The tolerance classes of the resistance thermometers are dened as follows in accordance with
IEC 60751:
Tolerance class Precision ∆t
Class B Basic accuracy ±(0.30 °C +0.0050|t[°C]|)
±1.8x0.30 °F +0.0050x|t[°F]-32|
Class A Increased accuracy ±(0.15 °C +0.0020|t[°C]|)
±1.8x0.15 °F +0.0020x|t[°F]-32|
Class AA (1/3 B) High accuracy ±(0.10 °C +0.0017|t[°C]|)
±1.8x0.10 °F +0.0017x|t[°F]-32|
Tolerances
The following tables provide an overview of the validity ranges of these tolerances. When you
use a thermometer above the specied limits, the values of the next lower accuracy class apply.
Action Tolerance Precision Range
Basic version Class B Basic accuracy -50 ... +400 °C (-58 ... +752 °F)
Class A Increased accuracy -30 ... +300 °C (-22 ... +572 °F)
Class AA (1/3 B) High accuracy 0 ... +150 °C (+32 ... +302 °F)
With increased vibra‐
tion resistance
Class B Basic accuracy -50 ... +400 °C (-58 ... +752 °F)
Class A Increased accuracy -30 ... +300 °C (-22 ... +572 °F)
Class AA (1/3 B) High accuracy 0 ... +150 °C (+32 ... +302 °F)
With extended measur‐
ing range
Class B Basic accuracy -196 ... +600 °C (-320 ... +1112 °F)
Class A Increased accuracy -100 ... +450 °C (-148 ... +842 °F)
Class AA (1/3 B) Increased accuracy -50 ... +250 °C (-58 ... +482 °F)
If an RTD will be subjected in a higher temperature as specied in the class, the sensor will be
declassied to the referring accuracy class. For enduring operation near 400 °C we recommend
the use of an extended measuring range RTD, instead of basic and increased vibration versions.
11.5 Measuring accuracy for thermocouples
Tolerance classes
The tolerance classes of the thermocouples are dened in the following table in accordance with
IEC 584/DIN EN 60584:
Technical data
11.5 Measuring accuracy for thermocouples
SITRANS TS100/TS200/TS300/TS500/TSinsert/TSthermowell
142 Operating Instructions, 08/2020, A5E47810090-AA