Detailed introduction of fault arc
Arc is a natural phenomenon in which an insulator is broken down by voltage, changes from non-conductive to conductive, and emits light and heat, commonly known as "arcing". Arc faults are characterized by suddenness, concealment, and randomness. Arc faults are common hazards in electrical circuits, occurring when the insulation or release of the circuit is poor. They may also occur at loose wire connections, as well as at connections between aging or damaged circuits and electrical circuits. Fault electrical arcs are generally divided into three types: series arc, parallel arc, and ground arc. In electrical short circuit fires, the risk of fire caused by grounding faults and arcing short circuits is the greatest, because the arc has a large impedance and voltage drop, which limits the fault current and prevents overcurrent protection appliances from operating or not operating in time to cut off the telephone. The local high temperature of the arcing can reach up to several amperes