What is the type of thermocouple _ instrument

Thermocouple is often used to measuring temperature, and it is based on the metal conductor resistance value increases with the increase of the temperature of the properties for temperature measurement. Mostly made of pure metal materials and heat resistance, 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. 1, ordinary type thermocouple: from the thermocouple temperature measurement principle, the measured temperature change 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. 2, thermocouple, thermocouple is by thermal components ( The resistor body) , wire, insulation materials, stainless steel casing combination solid body, its diameter is commonly phi - 2 Phi is 8 mm, achieve more xiaoke phi is 0. 25mm。 Compared with conventional type thermocouple, it has the following advantages: (1) small volume, no internal air gap, thermal inertia, small measuring hysteresis; (2) good mechanical properties, resistance to vibration and shock. (3) can bend, easy to install (4) long service life. 3, end thermocouple: end thermocouple temperature sensing element resistance wire winding by special processing, close to the face in the thermometer. Compared with general axial thermocouple, it can reflect more correctly and quickly end face of the actual temperature being measured, is suitable for measuring temperature bearing and other parts of the face. 4, flameproof thermocouple: 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 level zone with explosion danger place temperature measurement.