The working principle of thermocouples such as WIKA ashcroft

The working principle of thermocouples such as WIKA ashcroft

The working principle of a thermocouple is that two conductors with different compositions are welded at both ends to form a circuit. The direct temperature measurement end is called the measurement end, and the wiring terminal end is called the reference end. When there is a temperature difference between the measurement end and the reference end, thermal current will be generated in the circuit. When connected to a display instrument, the instrument will indicate the temperature value of the thermocouple and the corresponding thermoelectric electromotive force

注“t”为感温元件实测温度
热响应时间
在温度出现阶跃变化时，热电偶的输出变化至相当于该变化的50%，所需要的时间称为热响应时间，用T_0.5表示。
热电偶公称压力
***般是指在室温情况下保护管所能承受的静态外压而不破裂。实际上，容许工作压力不仅与保护管材料、直径壁厚有关，还与其结构形式，安装方法、置入深度以及被测介质的流速和种类等有关。