1. Thermocouple connector
Thermocouple connector is a kind of pluggable electrical connector specially used for quick connection of temperature measuring thermocouple, generally male and female paired use. In the thermocouple connector, the positive and negative electrode inserts are made of thermoelectric alloys of the same thermocouple model to reduce the temperature measurement error caused by the introduction of the connector. It should be noted that the fixing screws of the two positive and negative inserts are the other third metal, so during the temperature measurement process, the overall temperature of the connector must be consistent, otherwise the temperature measurement error will be brought about according to the law of the middle metal of the thermocouple.
2. Thermocouple feedthrough
The thermocouple feedthrough is a special form of thermocouple connector, which is mainly used to feed through the thermocouple signals inside and outside the vacuum vessel while maintaining airtightness. Like the thermocouple connector, the feedthrough also needs to be configured with the same thermocouple alloy material according to the corresponding thermocouple model. Due to the particularity of the vacuum environment, there is almost no convective heat transfer in the vacuum environment, which makes it easy to transfer heat to the feedthrough through thermal radiation and thermocouple wires, causing temperature unevenness and causing temperature measurement errors. Therefore, the feedthrough and the feedthrough All thermocouple connectors connected by the connector are not allowed to have other third metals, and the connection between the thermocouple wire and the thermocouple connector is crimping and winding.
3. The Difference And Correct Use Of Thermocouple Connectors And Feedthroughs
The main differences between connectors and feedthroughs are as follows:
(1) The use environment is different, and they are used for atmospheric pressure and vacuum respectively.
(2) There are no other third metals.
(3) Different influences on the accuracy of thermocouple temperature measurement.
It can be seen that because there is no third metal, the feedthrough has the least influence on the thermocouple temperature measurement, especially in a vacuum environment. Therefore, special attention must be paid in practical applications. The feedthrough cannot be used in conjunction with the connector. The fixing screw in the connector is the third metal material, which will inevitably have a greater impact on the temperature measurement of the thermocouple.
