Thermistor Temperature Sensor is a sensor thermometer that uses the principle that the resistance value of a conductor or semiconductor changes with temperature to measure temperature. It is widely used in industry, scientific research, medical and other fields, and has the characteristics of high measurement accuracy, good stability and high reliability. Thermistor Temperature Sensors are usually composed of sensitive elements (such as platinum, copper and other metals), connecting wires and display instruments. They can also be connected to temperature transmitters to convert temperature into standard current signal output.
The working principle of Thermistor Temperature Sensor is based on the characteristic that the resistance of metal conductors changes with temperature. When the temperature of a metal conductor rises, the vibration of atoms or molecules inside it intensifies, causing the movement of electrons in the conductor to be hindered, thereby increasing the resistance value. Conversely, when the temperature decreases, the resistance value decreases. By measuring the resistance value of the material, the corresponding temperature value can be calculated.
1. Measuring range
Temperature range -200℃ to +850℃ (some high-precision models can reach -200℃ to 1000℃)
Suitable for low temperature measurement, the lowest can reach 1K
2. Accuracy
Measurement accuracy ±0.1℃ (platinum RTD, such as PT100)
The accuracy of RTDs of different materials and designs varies, and the accuracy of copper RTDs can be ±1℃
3. Sensitive element materials
-Platinum (Pt): One of the most commonly used materials, with good temperature characteristics and stability, common models are PT10 and PT100
-Copper (Cu): Suitable for lower temperature ranges, such as -50℃ to 150℃
-Nickel (Ni): The measurement range is narrower, but the accuracy is higher, suitable for specific applications
4. Wiring method
- Two-wire system: Simple but with low accuracy, suitable for occasions with low measurement accuracy requirements
- Three-wire system: Commonly used in industrial process control, it can effectively eliminate the influence of lead resistance
- Four-wire system: The first choice for high-precision temperature detection, which can completely eliminate the influence of lead resistance
5. Output signal
- Standard current signal: Such as 4-20mA, which is convenient for long-distance transmission and integration with control systems
- Digital signal: Some high-end models provide digital interfaces (such as I2C, SPI), which is convenient for communication with computers or smart meters
6. Electrical characteristics
- Resistance value: For example, the resistance value of PT100 at 0℃ is 100Ω
- Supply voltage: Usually DC voltage, the range depends on the specific model, such as 2.7V to 5.5V
- Power consumption: Low power design, some models consume less than 1μA in standby mode
7. Environmental requirements
Working temperature range: Depends on the specific model and application environment, usually covers a wide temperature range
Waterproof, dustproof, anti-corrosion design, suitable for harsh industrial environments
8. Response time and stability
-Response time: Depends on the structure and measurement conditions of the sensor, at least 30 minutes for static gas and at least 5 minutes for liquid
-Stability: The ability to maintain measurement accuracy under long-term work, usually determined by materials and processes
9. Size and installation
-Size: Depends on the specific model and application requirements, ranging from small chips to large assembly types
-Installation requirements: It should be installed in a location with uniform temperature changes, avoid installation on valves, elbows, etc. to ensure accurate measurement
Thermistor Temperature Sensor is widely used in various industrial process control, scientific research experiments, medical equipment, food processing, HVAC systems, fire safety and other fields. In industrial production, it can be directly inserted into pipes, heat exchangers, reactors and other equipment to monitor temperature changes in real time to ensure production safety and product quality. In medical equipment, it is used in thermometers, blood analyzers, etc. to accurately measure the temperature of human bodies or biological samples.
