PT100 temperature sensor, also known as platinum thermistor
Thermal resistance is the most commonly used temperature detector in the medium to low temperature range. Its main characteristics are high measurement accuracy and stable performance. The measurement accuracy of platinum thermistor is the highest among them. It is not only widely used in industrial temperature measurement, but also made into a standard reference instrument. The temperature sensing elements of the metal thermistor have a cross framework structure of quartz sleeve, a rod structure of Fried Dough Twists framework structure, etc. There are many types of temperature sensing materials commonly used in metal thermistors, with platinum wire being the most commonly used. In addition to platinum wire, metal thermal resistance materials used in industrial measurement also include copper, nickel, iron, iron-nickel, tungsten, silver, etc. Thin film thermistors are manufactured using the method of electron cathode sputtering, which can achieve industrial large-scale production. The skeleton is made of ceramics, and the lead wire is made of platinum palladium alloy.
The temperature measurement principle of thermal resistance is different from that of thermocouple. Thermal resistance is based on the thermal effect of resistance for temperature measurement, that is, the characteristic of the resistance value of the resistance body changing with temperature. Therefore, as long as the resistance change of the temperature sensing thermal resistance is measured, the temperature can be measured. At present, there are mainly two types of metal thermistors and semiconductor thermistors.
The most widely used thermoelectric materials currently are platinum and copper: platinum has high resistance accuracy, is suitable for neutral and oxidizing media, has good stability, and has a certain degree of nonlinearity. The higher the temperature, the smaller the rate of resistance change; Copper resistance has a linear relationship with temperature within the temperature measurement range, with a large number of temperature lines. It is suitable for non corrosive media, and is prone to oxidation if it exceeds 150. The most commonly used ones in China include R0=10 Ω, R0=100 Ω, and R0=1000 Ω, with graduation numbers of Pt10, Pt100, and Pt1000, respectively; There are two types of copper resistors, R0=50 Ω and R0=100 Ω, with their division numbers Cu50 and Cu100. Among them, Pt100 and Cu50 are the most widely used.
