The main influencing factors of measurement errors in platinum rhodium thermocouples

1, Selection of temperature measurement points
The installation position of WRP-130 platinum rhodium thermocouple, that is, the selection of temperature measurement points, is important. The location of the temperature measurement point must be typical and representative for the production process, otherwise it will lose the significance of measurement and control.
2, Insertion depth
When a thermocouple is inserted into the measured location, heat flow will be generated along the length direction of the sensor. When the ambient temperature is low, it will
There is heat loss. Causing temperature discrepancies between the thermocouple and the object being measured, resulting in temperature measurement errors. In short, the error caused by thermal conduction is related to the insertion depth. The insertion depth is also related to the material of the protective tube. Metal protective tubes should be inserted deeper (about 15-20 times the diameter) due to their good thermal conductivity, while ceramic materials have good insulation properties and can be inserted shallower (about 10-15 times the diameter). For engineering temperature measurement, the insertion depth is also related to the stationary or flowing state of the measurement object. For example, the measurement of the temperature of flowing liquids or high-speed airflows will not be limited by the above. The insertion depth can be shallower, and the specific value should be determined experimentally.
3, The impact of response time
The basic principle of contact temperature measurement is that the temperature measuring element needs to reach thermal equilibrium with the measured object. Therefore, it is necessary to maintain a certain amount of time during temperature measurement in order to achieve thermal equilibrium between the two. The duration of the holding time is related to the thermal response time of the temperature measuring element. The thermal response time mainly depends on the structure and measurement conditions of the sensor, with significant differences. For gas media, especially stationary gases, it should be maintained for at least 30 minutes to reach equilibrium; For liquids, it should be faster than 5 minutes.