The resistance-temperature characteristic of a PTC component refers to the relationship between the zero-power resistance value of the component and the temperature of its resistor under the specified measurement voltage. The picture on the right is the R-T characteristic diagram. In the picture, group A is high Curie point PTC thermistor (Tc≥120℃), group B is low Curie point. Type A is generally used for temperature sensing, overheating protection, motor starters and high temperature heating elements. Type B is generally used for temperature sensing, overcurrent protection, delay components and automatic demagnetizers.