Shuo PPTC self-recovery fuse is a thermistor with positive temperature coefficient polymer, which is used for overcurrent protection and can replace current fuse. When the circuit works normally, its resistance value is very small (voltage drop is very small). When the temperature of the circuit rises due to overcurrent, the resistance value increases sharply by several orders of magnitude, which reduces the current in the circuit below the safe value, thus protecting the following circuit and automatically restoring to the low resistance value after the overcurrent disappears. The effect is similar to that of the switch part, but the response speed is slow. What are the advantages of Shuokai PPTC self-recovery fuse in automobile? The following is a detailed answer for everyone.
1. protection of PPTC self-recovery fuse for automobile cigarette lighter circuit.
Automobile cigarette lighters usually need to adapt to strict application environment, so they are prone to various abnormal situations such as overcurrent. When the cigarette lighter circuit is used as the charging power of mobile phone, if it is used improperly (such as excessive load, everse connection of electrodes, short circuit of load, etc.). ), the cigarette lighter circuit may be damaged or the charging circuit may be damaged. It is difficult for ordinary users to use disposable fuses for protection, which need to be replaced after failure. If the PPTC self-recovery fuse of SOCAY Shuokai Electronics, an agent of our company Shunhai Technology, is used for over-current protection, protection will be implemented in case of failure, and automatic recovery will be performed after troubleshooting, which has the advantage of not needing frequent replacement.
Second, that PPTC self-recovery fuse protect the power supply system of automobile window.
The window power supply system needs a large current, so it needs a thick wire, otherwise, the wire may overheat or even burn. For example, connecting SOCAY Shuokai Electronics, the agent of Shunhai Technology, into the PPTC self-recovery fuse of the line can reduce the diameter of the line and ensure the safety of the line at the same time. The increase of line resistance will not affect the speed of window switch and the pressure of window. This can greatly reduce the cost of the window power supply system.
Conclusion: Circuit designers should mainly consider both static and dynamic aspects when choosing overcurrent devices to restore fuses. Static refers to voltage, current, ambient temperature, size, fault current, etc. Dynamic refers to fusing time, melting heat value, etc., which are the key points of fuse product selection and design. Secondly, after passing the theoretical calculation of fuse, it needs to be tested and verified in combination with the field, and the ideal design scheme is finally reached by means of reliability analysis. Shuokai Electronics EMC Lab supports ISO7637 5a/5b load impact test for automotive electronics.
