What is the working principle of thermocouple _ instrument2

Thermocouple is usually and display meter, recording meter and electronic regulator. It can be directly measured from various production process 200 ℃ to + 600 ℃ within the scope of the liquid, steam and gas medium and the temperature of the solid surface. Thermocouple is commonly used in low temperature zone of a kind of temperature measuring element. Thermocouple resistance using material when the temperature changes itself along with the change of characteristics to measure temperature. Thermocouple heated parts ( Thermal element) Is uniform with fine wire wrapped around the insulation materials on the skeleton of measured medium in the presence of temperature gradient, temperature is measured by thermal element is located within the scope of average temperature in the medium layer. Its main characteristic is high accuracy, stable performance. The platinum thermocouple measuring accuracy is high. The structure characteristics of the thermocouple, 1) Wz series platinum thermocouple assembly: usually by the temperature sensing element, main parts, such as installing fixtures and connection box with high measuring accuracy, stable and reliable performance, etc. Practice with pt100 platinum thermocouple is most widely used. ( 2) WZPK series platinum thermocouple, thermocouple is by the thermal components, wire, insulation materials, stainless steel casing combination solid body, it has the following advantages: slender shape, heat fast response time, vibration resistance, long service life, etc. ( 3) Flameproof thermocouple: flameproof thermocouple, through the special structure of the junction box, the box inner explosive mixed gas by affected by sparks or electric arc explosion limit within the junction box, production site won't explode. ( 4) End thermocouple: end thermocouple temperature components made by special processing of the resistance wire, close to the face in the thermometer. Compared with general axial thermocouple, it can reflect more correctly and quickly measured end face of the actual temperature, suitable for measuring the surface temperature. The working principle of thermocouple core under the effect of temperature, the resistance wire resistance change and change. Can be used to measure - 200 ℃ ~ + 800 ℃ temperature range. Its advantage is minimal deviation. Because of its good electrical output performance, thermocouple can be adjusted for the display, recorder, instrument, scanner and computer to provide accurate input values. Thermocouple is the thermal resistance of core material, its measurement principle is based on the metal conductor resistance value increases with the increase of the temperature of the properties for temperature measurement. Thermocouple temperature materials are mostly made of pure metal materials, the current application is a lot of platinum and copper, in addition, now began to use the materials such as nickel, manganese and rhodium. Thermocouple temperature measurement principle is based on a conductor or semiconductor resistance changes with the temperature change and this feature to measure temperature and parameters related to the temperature. Thermocouple are mostly made of pure metal materials, the application is a lot of platinum and copper, now have begun to use the materials such as nickel, manganese and rhodium thermocouple. Thermocouple is usually need to get the resistance signal through wire transfer to the computer control device or other secondary instrument.