Thermocouple cables has a pair of insulated wires with the same nominal value of the thermoelectromotive force of the matched thermocouple within a certain temperature range (including normal temperature). Use them to connect the thermocouple and the measuring device to compensate them and the thermoelectric The error caused by the temperature change at the even connection. In order to improve the anti-interference of the thermocouple connecting wire, shielded compensation wire can be used. For occasions with many on-site interference sources, the effect is better. However, the shielding layer must be strictly grounded, otherwise the shielding layer will not only not play a shielding role, but will enhance interference. The compensation wire is used to extend the cold end of the hot electrode, that is, the mobile thermocouple, and is connected with the display instrument to form a temperature measurement system. Equivalently adopts the national standard of IEC 584-3 “Thermocouple Part III-Compensation Wire”. The products are mainly used in various temperature measuring devices and have been widely used in nuclear power, petroleum, chemical, metallurgy, electric power and other sectors.