The Voltage across a Fuse during the Current Interruption Process

Experimental investigation of the fusion in cylindrical exploding wires using high current densities with industrial frequency

“…At some instant before the material is completely vaporized, the metallic coherence within the fuse wire is interrupted and an arc is formed. [3,7,12]. However, it is doubtful whether this phenomenon will occur in a regular way or whether the liquid cylinder will explode under the mechanical action of the vapor pressure.…”

“…However, it is doubtful whether this phenomenon will occur in a regular way or whether the liquid cylinder will explode under the mechanical action of the vapor pressure. [3,7,8,12]. According to the literature there is another action that could lead to arcs formation in fusible wires.…”

“…If the source voltage of the circuit is sufficiently high, small arcs arise between these globules. This phenomenon is referred as "multiple arcing" and it has been observed [1,2,3,7,16]. With the volatilization and interruption of the metallic coherence, electric arcs are formed (arcing period) between the remaining solid parts of the conducting material, in an environment of metal vapors.…”

“…This dynamic process gives rise to rapid increase in the electric resistance of the arc and its eventual extinction [1,2,3,6,12]. The metal vapor column, which arises during the evaporation process of a fusing wire surrounded by air, expands very rapidly due to the high pressure in this vapor, as has been made visible with cylindrical wires in the past [7]. The theoretical and experimental investigation concerning the exploding wires showed that fuse elements, after reaching the evaporation temperature under atmospheric conditions, could become highly superheated in the liquid state [9÷11,17].…”

“…The fuse resistance in these circumstances is determined by the cross-section of the metal vapor column, the length of this column and the specific resistance of the ionised metal vapor. Experiments showed that the cross-section of the metal vapor column depends on the current [1,2,7,17]. In this metal vapor column the arcs are formed.…”