Principles and Technical Exchange of Traditional, Pyrotechnic, and Smart Fuses

This document provides a comprehensive overview of traditional, pyrotechnic, and smart fuses, focusing on their principles, structures, and technical differences. It begins by defining a traditional fuse as a passive protection device that uses the thermal effect of current to melt a fuse element and interrupt fault current under specified voltage conditions. The main products include EV series fuses for electric vehicles, RS308-HB round tube bolt-connection fast-acting fuses, RS309 round tube DC fast-acting fuses, RS306 low power consumption high-speed current-limiting fuses, PV series fast-acting fuses for photovoltaic systems, RSZ307 fast-acting fuses for DC applications, and RT/NH type knife-blade contact fuses. The structure of a typical round tube fuse is detailed, including contact terminals, fuse elements with notches, arc extinguishing medium (quartz sand), and tube housing. The document explains the differences between Class g and Class a fuses, highlighting the use of low-temperature alloy melting effect points for overload protection. It also describes the complete interruption process, from pre-arcing to arcing stages, and discusses key parameters such as prospective short-circuit current, peak let-through current, and operating time. The comparison between AC and DC fuses is addressed, emphasizing the importance of fault overcurrent and prospective current in fuse selection.