What is the working principle of thermocouple _ instrument1

Thermocouple is the use of the material when the temperature changes, the resistance also along with the change of characteristics to measure temperature. When resistance changes, the work shows the temperature resistance of the meter. Thermocouple is a kind of temperature sensor, it is smaller than the diameter of a prefabricated thermocouple, flexible, good vibration resistance, suitable for installation in the case of prefabricated thermocouple can't install, WZPK thermocouple series adopts imported thermocouple temperature measuring element, therefore, is accurate, sensitive, quick thermal response time, stable quality, long service life, etc. Thermocouple protective mining have stainless steel, full of high-density oxide material inside insulation, therefore, thermocouple strong pollution resistance and mechanical strength, suitable for installation in harsh environment. Thermocouple temperature measurement is based on the metal conductor resistance value increases with the increase of the temperature of the properties for temperature measurement. Thermocouple with small volume, small measurement lag, good mechanical properties, resistance to vibration, shock, can bend, easy installation, long life and other characteristics, is one of the commonly used in the low temperature zone temperature detector, and is widely used in industrial temperature measurement. In use, we found that the thermocouple type many, the application is a lot of platinum and copper. Four common types of thermocouple: master type thermocouple, thermocouple, end thermocouple, flame-proof platinum resistance 1, proficient in type thermocouple: industrial commonly used thermocouple temperature sensing element ( The resistor body) The structure and characteristics. From the thermocouple temperature measurement principle, the measured the change in temperature is directly measured by thermocouple resistance change, therefore, the wires of a thermocouple body such as a variety of wire resistance change will affect temperature measurement. As to eliminate the influence of the lead resistance with the three wire or four wire system. 2, thermocouple, thermocouple is by thermal components ( The resistor body) , wire, insulation materials, stainless steel casing combination solid body, its diameter is generally from 2 to 8 mm, achieve more xiaoke phi is 0. 25mm。 3, end thermocouple: end thermocouple temperature sensing element resistance wire winding by special processing, close to the face in the thermometer, it is compared with general axial thermocouple, can more accurately and quickly to reflect the actual temperature of end face, is suitable for measuring temperature bearing and other parts of the face. 4, flame-proof platinum resistance: flameproof thermocouple through the special structure of the junction box, its shell internal explosive mixed gas by affected by sparks or electric arc explosion limit within the junction box, that wouldn't make production field explosion. Flameproof thermocouple can be used in the bla ~ b3c zone with explosion danger place temperature measurement.