automotive blade fuse manufacturers_mini cooper fuse box factory

22 2024-08

　　The protective effect of PPTC mainly relies on the following aspects

　　1. Material characteristics: The material used in PPTC is a polymer composite material that has a certain degree of conductivity and can normally allow current to pass through. However, when overheating occurs, the volume of the material rapidly expands, causing the polymer to melt and interact with the conductive filler, resulting in instantaneous high resistance. This feature enables PPTC to quickly cut off current and provide protection.

　　2. Thermal sensitivity: The material of PPTC has thermal sensitivity, and when current passes through PPTC, the material will generate heat due to resistance. When the current is too high, the temperature of the material will increase. When it reaches a certain threshold, the material will undergo a change in phase transition properties, which will quickly cause an increase in resistance. This thermal sensitive characteristic enables PPTC to respond promptly and quickly cut off the circuit in the event of current overload or short circuit.

　　3. Structural design: The structural design of PPTC is also an important factor in achieving protective effects. PPTC usually has two electrodes with a conductive path between them, which contains many conductive fillers to ensure that current can pass through. When the current is overloaded or short circuited, the conductive filler will locally melt and interact with the material to produce high resistance. At this point, due to the expansion and melting of the material volume, the conductive path is cut off and current cannot pass through. This structural design enables PPTC to quickly cut off current in the event of a fault, protecting other components.

　　4. Self recovery feature: The self recovery feature of PPTC is a very important feature. Once the fault is repaired, PPTC can automatically return to normal state and continue operation. This is because when current passes through PPTC, it will cause resistance heat, which will be transferred to the material. When the current is cut off, the material will cool down and return to a low resistance state, allowing it to resume normal operation. This self recovery feature makes PPTC highly reliable and reusable in circuits.

　　In summary, PPTC (self recovering fuse) achieves protection for circuits through its special material properties, thermal sensitivity, structural design, and self recovering characteristics. It can quickly cut off the current and protect other electronic components from damage. The use of PPTC in circuits can greatly improve the safety and reliability of the circuit, and reduce the risk of faults. PPTC plays an important role in electronic products and circuit protection, and its design and application will further promote the development of the electronics industry.