The temperature sensor is very accurate for the measurement of ambient temperature and is widely used in agriculture, industry, workshops, warehouses and other places. There are many types, with different temperature sensing elements and different models. The following briefly introduces the classification of temperature sensors.
 
Classification by the temperature sensing element can be roughly divided into three categories: platinum resistance temperature sensor, thermocouple temperature sensor, and thermistor temperature sensor.
 
1: Platinum thermal resistance temperature sensor
 
Platinum thermal resistance is designed and manufactured using the basic principle of platinum wire's resistance value changing with temperature. According to the resistance value R (℃) at 0℃, it can be divided into 10 ohms (graduation number Pt10) and 100 ohms (graduation number Pt100), etc. The temperature measurement range is -200~850℃. The models that use PT100 platinum thermal resistance as the temperature sensing element include armored, assembled, socket, and end thermal resistance, and the measurable range is -200 degrees Celsius to 150 degrees Celsius, and -50 degrees Celsius to 850 degrees Celsius. It is mainly used in industries that require small temperature errors or precision instruments.



2: Thermocouple temperature sensor
 
The thermocouple temperature sensor is mainly welded together by two different metal materials. When the main temperature changes, different electric potentials will be generated at the two ends. The corresponding temperature changes are obtained through the change of electric potential. Measurable temperature: up to 2300 degrees, K-type positive stage is more acceptable in high temperature section.
 
3: Thermistor
 
Composed of metal oxide ceramics, it is a low-cost, most sensitive temperature sensor. Temperature measurement range: small temperature range -50 to 200 degrees, small size, fast response time. Because of its low price, it has been applied to many household appliances.