Platinum rhodium thermocouple is high temperature metal thermocouple, thermocouple are created using the principle of physics of temperature measuring instrument, the main characteristics of platinum rhodium thermocouple is high temperature resistant, platinum rhodium thermocouple application scope is very broad. Platinum rhodium thermocouple has five big performance used in various industries have a large role. Platinum-rhodium thermocouple 5 big performance: the physical and mechanical properties in general with compensation conductor insulation and sheath of physical properties and aging properties should comply with the regulations of table 5. Moisture resistant to heat with compensation conductor should be subjected to the environment temperature of 40 + 2 ℃, relative wet 95 plus or minus 3%, moistureproof performance over 24 hours after the test, the compensating conductor wire core and line between core and shielding layer between the insulation resistance of not less than 25 m Ω per meter. Heat resistance to heat with compensation conductor should be subjected to 220 + 5 ℃ for 24 hours after the thermal performance test, the sample immediately in the 5 times the diameter of the cylinder on the curved surface should be no crack after 180 degrees, compensation conductor line between the core and wire core and shielding layer between the insulation resistance of not less than 25 m Ω per meter. Low temperature performance generally use compensation conductor should be sustained - winding After 20 ℃ low temperature winding test, with visual observation winding in the specimen on the test bar insulation should be no cracks. Insulation resistance when the ambient air temperature is 15 35 ℃, relative humidity is not more than 80%, the compensating conductor wire core and wire core and shielding layer between the insulation resistance between not less than 5 m Ω every 10 metres.