In general, in order to facilitate the monitoring and measuring instrument operation of instrument will be placed on basic constant temperature and facilitate set console, away from the actual temperature measuring point has a certain distance. In the distance, in general situation is more complex, passes through power supply, for example, have electromagnetic interference and so on, and may often be the role of external force. While using thermocouple wire may cause the error of measurement, use is easy to be damaged, often need to change, and so on. And thermocouple wire materials are generally more expensive, if used for long distances, the cost is very high. These, are the reasons why using thermocouple compensating conductor. To sum up, the use of compensating conductor has the following advantages: 1) Improve physical properties and mechanical properties of thermocouple temperature measurement circuit, using multi-strand wire core or small diameter flexible compensation wire line can be improved, convenient wiring, also can adjust circuit resistance or blocking interference; 2) Measuring circuit to reduce costs, distance when the thermocouple and measuring devices, and using the compensating conductor can save a lot of thermocouple material, especially when using the precious metal thermocouple. The classification of the thermocouple compensation wire thermocouple compensation conductor should be divided into two categories: 1) Extended type compensation conductor should be extended type compensation wire is also called extended type wire, the wire in the name of the chemical components and the thermoelectric emfs nominal value and the thermocouple, the same with the letter 'X' attached to the thermocouple said after graduation, such as 'KX' said K type thermocouple with compensation conductor should be extended type. 2) Compensation type compensation conductor type compensation compensation wire, also known as compensation wire, the wire in the name of the chemical composition and thermocouple are different, but the value of thermoelectric emfs, at 0 100 ℃ or 0 200 ℃ with with thermocouple thermoelectric emfs nominal values are the same, with the letter 'C' attached to the thermocouple said after graduation, such as 'KC'. Different wire can be applied to the same degree of thermocouple, and additional letters. 3, how to correctly choose thermocouple compensation wire 1) Compensation conductor index number must be consistent with the thermocouple used, such as K type thermocouple, must use the K type coupling compensation. 2) Choose according to using the environment temperature, low compensation conductor operating temperature range, 0 - general points 100 ℃ and 0 0 to 200 ℃ of two Lower the price of 100 ℃, can choose according to actual need. 3) If the interference sources, can choose anti-jamming strong compensation conductor shielding type. 4) If there are multiple temperature measuring points at the same time, can choose to have multiple sets of compensation wire cable.