air conditioner fuse keeps tripping_mini cooper fuse box factory

04 2024-09

　　Working principle of fuse

　　1、 Working principle of fuse

　　When the fuse is powered on, the heat converted from electrical energy increases the temperature of the fusible item. When passing through normal operating current or allowable overload current, the heat generated is radiated to the surrounding environment through the melt and shell, and the heat generated by convection, conduction, etc. gradually balances with the generated heat. If the generated heat is greater than the dissipated heat, the excess heat will gradually accumulate on the meltable object, causing its temperature to rise; When the temperature reaches and exceeds the melting point of the meltable material, it will melt, melt, and cut off the current, playing a role in protecting the circuit.

　　2、 Terminology of fuses

　　Rated current: The nominal operating current of the fuse tube (the maximum current that the fuse can maintain normal operation for a long time under normal conditions).

　　Rated voltage: The nominal operating voltage of the fuse (the maximum voltage that the fuse can safely withstand when disconnected). When selecting a fuse, the rated voltage of the selected fuse should be greater than the input voltage of the protected circuit.

　　• Breaking ability: When there is a large overload current (such as a strong short circuit) in the circuit, the fuse can safely cut off (break) the maximum current of the circuit. It is the most important safety indicator for fuses. Safe disconnection refers to something that splashes, burns, or endangers surrounding components, electronic components, and even personal safety, and will not explode in the disconnection circuit.

　　Overload capacity (load carrying capacity): The maximum overload current that a fuse can maintain for a specified period of time. When the current flowing through the fuse exceeds the rated current, the temperature of the fusible item will gradually increase after a period of time and eventually melt.

　　The UL standard stipulates that the fuse should remain in operation for more than 4 hours, with a maximum unfused current of 110% of the rated current (100% for miniature fuse tubes)