How to identify the quality of the thermistor.Pyroelectric infrared sensor lens

　　Thermistors have different temperature response parameters, and the temperature response curve of the thermistor under test should be obtained first. Use a resistance meter to measure the resistance of the thermistor at different ambient temperatures:

　　1. Normal temperature detection (indoor temperature is close to 25 ℃), use alligator clips instead of test leads to clamp the two pins of the PTC thermistor to measure the actual resistance value, and compare with the nominal resistance value, the difference between the two is ±2Ω Inside is normal. If the actual resistance value is too different from the nominal resistance value, it means that its performance is poor or damaged.

　　2. Heating test, on the basis of normal temperature test, the second step test - heating test can be carried out, a heat source (such as an electric soldering iron) is heated close to the thermistor, and the multimeter is observed. If you can see that the multi-function indication changes with the increase of temperature.

　　This indicates that the resistance value is changing gradually (the resistance value of NTC of the negative temperature coefficient thermistor will become smaller, and the resistance value of PTC of the positive temperature coefficient thermistor will become larger). When the resistance value changes to a certain value, the displayed data will gradually stabilize. , indicating that the thermistor is normal, if there is no change in the resistance value, indicating that its performance has deteriorated and cannot be used continuously.

　　Through the introduction of the above article, I believe that you have already understood the thermistor and the method of identifying the quality of the thermistor. The thermistor has a wide range of applications. Wherever "temperature control" is required, most of the thermistors are used. Because the thermistor has high sensitivity, and is cheap and cost-effective. For example, computer CPU, electric water heater overheating protection, etc., all use thermistor protection.

Read recommendations:

Energy storage fire protection and NTC temperature sensor.Infrared sensing module

Suitable for ultra-low temperature NTC thermistors.Small Human Body Sensor price

HW-MS07 microwave sensor module

PIR Lens 7708-1

HW-M10-2 microwave sensor module