How to use thermocouples correctly?

At present, there are several types of thermocouples commonly used in industrial production, including S, K, E, N, and J. When purchasing thermocouples, one should choose thermocouples with the same scale as the measuring instrument.
Selection of Thermocouples. At present, there are several types of thermocouples commonly used in industrial production, including S, K, E, N, and J. When purchasing thermocouples, one should choose thermocouples with the same scale as the measuring instrument. When multiple temperature measuring instruments are used simultaneously while meeting the requirements of the process specifications, thermocouples with the same division number should be selected as much as possible to prevent the mixing of thermocouples with different division numbers and measuring instruments due to human factors, which may lead to quality accidents.

2. The measuring end of the thermocouple should be securely inserted into the end of the protective tube to ensure the accuracy of the measurement results. 3. The connection of the instrument must use compensation wires that are compatible with the thermocouple. The positive and negative poles of the thermocouple and compensation wires should be connected correctly. Otherwise, not only will it fail to compensate, but it will also bring greater errors to the measurement results. 4. The thermocouple in use should be protected in the junction box. The junction box of the thermocouple is used to connect the thermocouple and the measuring instrument. In order to prevent contamination of the thermocouple, the outlet and cover of the junction box are sealed with gaskets. During use, the sealing gaskets should be protected to prevent loss and damage. 5. Ensure the integrity of insulation materials. In a thermocouple circuit, if the insulation between the two hot electrodes is poor or short circuited, it will cause measurement errors or inability to measure. Therefore, it should be ensured that the two hot electrodes are always separated by insulating materials. 6. Thermocouples in use should be regularly sent to the metrology department for calibration, and thermocouples that fail the calibration should be replaced in a timely manner; Newly purchased thermocouples should be calibrated before being put into use. The calibration cycle for thermocouples is generally six months.