The Chinese standards for thermocouple temperature sensors are largely consistent with international standards. Since January 1, 1988, all thermocouples and thermal resistors in China have been manufactured in accordance with IEC international standards. The specific comparison is as follows:
Standard Corresponding Relationship: The new version of China's national standard GB/T 16839.1 is equivalent to the IEC 60584 series standards. For example, GB/T 16839.1-1997 is equivalent to IEC 60584-1:1995 and IEC 60584-2:1982, while the latest version of GB/T 16839.1 is equivalent to IEC 60584-1:2013.
Thermocouple Types: China's standards cover 10 types of thermocouples, including Type R, S, B, J, T, E, K, N, C, and A, which is consistent with international standards. Among them, seven types (S, B, E, K, R, J, and T) are uniformly designed thermocouples in China.
Electromotive Force (EMF) Specifications and Tolerances: China's standard GB/T 16839.1-2018 clearly specifies the EMF specifications and tolerances for thermocouples. For instance, the tolerance of Type K thermocouples in the temperature range of 0-400℃ has been adjusted from ±1.6℃ to ±1.0℃. These provisions are in line with international standards, ensuring the measurement accuracy and consistency of thermocouples at different temperatures.
Measurement Basis: The measurement of thermocouple EMF in Chinese standards is based on the "International Temperature Scale (ITS-90)", which is consistent with international standards. The actual EMF value of the thermocouple is determined by comparing the thermocouple with a standard platinum resistance thermometer in the same temperature field.