The working principle of PT100 temperature sensor
The Working principle Of PT100 Temperature Sensor
PT100 temperature sensor is also called platinum thermal resistance.
Thermal resistance is one of the most commonly used temperature detectors in medium and low temperature regions. Its main features are high measurement accuracy and stable performance. Among them, platinum thermal resistance has the highest measurement accuracy. It is not only widely used in industrial temperature measurement, but also made into a standard benchmark. The temperature sensing element of the metal thermal resistance has a quartz sleeve cross skeleton structure, a twist skeleton structure and a rod structure. There are many types of temperature-sensing materials commonly used in metal thermal resistors, and platinum wire is the most commonly used. In addition to platinum wire, metal thermal resistance materials for industrial measurement include copper, nickel, iron, iron-nickel, tungsten, silver, etc. Thin film thermal resistance is manufactured by electronic cathode sputtering, which can realize industrialized mass production. The skeleton is made of ceramics, and the lead is made of platinum-palladium alloy.
The temperature measurement principle of the thermal resistance is different from that of the thermocouple in that the thermal resistance is based on the thermal effect of the resistance to measure the temperature, that is, the resistance of the resistor changes with the temperature. Therefore, as long as the resistance change of the thermal resistance is measured, the temperature can be measured. At present, there are mainly two types of metal thermistors and semiconductor thermistors.
At present, the most widely used thermal resistance materials are platinum and copper: platinum resistance has high precision, is suitable for neutral and oxidizing media, has good stability, and has a certain nonlinearity. The higher the temperature, the smaller the resistance change rate; In the temperature range, the resistance value and temperature are linear, and the number of temperature lines is large, which is suitable for non-corrosive media, and is easily oxidized when it exceeds 150. The most commonly used ones in China are R0=10Ω, R0=100Ω and R0=1000Ω, and their graduation numbers are Pt10, Pt100, Pt1000 respectively; copper resistors have R0=50Ω and R0=100Ω, and their graduation numbers are The numbers are Cu50 and Cu100. Among them, Pt100 and Cu50 are the most widely used.
