Armored platinum-rhodium thermocouple is mainly used to measure the temperature of gas, liquid or solid in the middle and high temperature occasions of 0~1300℃, usually with the measurement and control instrument, recorder and other supporting use. Mainly used in glass, ceramics, iron and steel metallurgy, salt bath furnace and other occasions temperature measurement. Armored platinum-rhodium thermocouple consists of thermocouple wire, protective sleeve and lead or junction box, and the protective sleeve material is made of high temperature resistant GH3030 or GH3039. The difference between armored platinum-rhodium thermocouple and platinum-rhodium thermocouple is that armored platinum-rhodium thermocouple external protection sleeve is made of metal material, its length is not limited, in the process of transportation, delivery, installation and use can be free bending and not easy to deformation and fracture; The platinum-rhodium thermocouple is usually external protective sleeve for ceramic tube and corundum tube, which is easy to break in the process of transportation, delivery, installation and use. In the applicable temperature measurement, armored platinum-rhodium thermocouple measurement temperature of 0~1300℃, and platinum-rhodium thermocouple can measure 0~1600℃. Therefore, appropriate thermocouple products should be selected according to different temperature measurement requirements on site. 1, protective tube diameter: GH3030 GH3039 2, material: GH3030 GH3039 3, accuracy grade: Ⅱ 4, suitable for thermocouple grading number: S type B type 5, armored length: > 300mm four, model and measuring temperature range