Arc characteristics on dissymmetric contact pair of Ag based materials at slowly breaking

In this study, we newly attempt to clarify the material dependencies of arc characteristics at slowly breaking contact changing by the Ag based different material pairs. Firstly, the contact voltage, current waveforms and arc columns are measured. Secondary, the material dependencies of the arc duration, the spread and concentration of the arc column are discussed. Finally, the arc voltage fluctuation is discussed. Experimental results show that in the cases of the (+)Ag-Ag(-) and (+)AgSnO₂(-)Ag, arc durations can be shorter. The arc duration influenced by the cathode electrode material. The voltage fluctuation larger than the supply voltage is observed in the (+)Ag-(-)Ag case. The (+)AgSnO₂-(-)Ag contact pair has relatively small voltage fluctuation. The condition of dissymmetric contact pair in the case of the (+)AgSnO₂-(-)Ag is one of the solution to make shorter duration and smaller voltage fluctuation of arc discharge. This study provides the basic considerations on the short arc extinction for DC switching.