The main uses of platinum rhodium thermocouples

The working principle of platinum rhodium thermocouple is believed to be understood by many friends. Firstly, platinum rhodium thermocouple is mainly composed of two completely different components of conductors. When the two ends are combined into a circuit, when the temperature of these two junction points is different, thermal current will appear in the circuit. But when there is a temperature difference between the working end and the reference end of the thermocouple, the displayed instrument will indicate the temperature value corresponding to the thermoelectric potential generated by the thermocouple. If the measured temperature is normally maintained between 1000 ℃ and 1300 ℃, it is recommended to use a single platinum rhodium thermocouple. However, when the measured temperature is between 1200 ℃ and 1600 ℃, a dual platinum rhodium thermocouple can be used. This ensures that the temperature used is within the range and guarantees the final service life of the platinum rhodium thermocouple.

Platinum rhodium thermocouples have high accuracy and stable performance throughout the entire series. The main reason is that the temperature range for temperature measurement is relatively wide, resulting in a longer service life. Additionally, the upper limit for temperature measurement is relatively high, which are the main factors for selecting platinum rhodium thermocouples. Platinum rhodium thermocouples are more suitable for use in inert and oxidizing atmospheres, but can also be used for short-term use in vacuum atmospheres. However, they are not suitable for use in atmospheres containing metal, reducing, and non-metallic vapors. And the advantage of platinum rhodium thermocouples is that there is no need to use compensating wires to compensate for it, because the thermoelectric potential within the specified range will be relatively small. The disadvantage of platinum rhodium thermocouples is that their thermoelectric potential is relatively low, resulting in lower sensitivity. If they are used at high temperatures, the overall mechanical strength will decrease and they will be very sensitive to pollution. Due to the expensive materials of precious metals, the one-time investment will be relatively large.