company news about Internal structure of special fuse for new energy vehicles

        The fuse is a calibrated current carrying device. A typical fuse is composed of one or more melts surrounded by a filler (such as silica sand) as an arc extinguishing medium. For applications in different areas, the fuse styles and installation methods are different, but the fuse structures are basically the same

        Among them, melt material, melt notch configuration, filler and processing quality all affect the breaking performance of the fuse. At present, the fuse melt for EV/EVP in the market is mainly made of silver, and the melt shape can be divided into ribbon and filament to a certain extent. Changing the section shape can significantly change the fuse fusing characteristics.

        The main body of the fuse housing shall be made of ceramic (with good heat conduction and temperature resistance) or epoxy glass fiber tube (with high bending strength and low cost) series with certain pressure bearing and temperature resistance. Generally, quartz sand (with good and stable physical/chemical properties) is selected as the filler (effectively reducing the gas gap in Fuse) to provide effective heat transfer through the filler and absorb the arc energy during over-current breaking (different filling methods of the filler affect the arc extinguishing and breaking energy)

        Under normal conditions, the fuse carries current. When a continuous over-current occurs, the fuse generates heat at a faster rate than the filler. If the over-current persists, the melt notch will reach its melting point and be disconnected. The greater the overcurrent, the faster the melt melts, that is, the fuse has inverse time current characteristics, which is also an ideal characteristic for protecting conductors and electrical equipment.