Experimental Analysis of Transient Phenomena from Metal Melting to Electric Discharge during Breaking Operations of Electric Contacts

摘要

During breaking contact, contact voltage v_c shows irregular, random, or unexpected responses after v_c=U_m until mechanical contact current shutdown or arc ignition. Dependence of these phenomena on power source voltage, energizing current, and residual inductance was confirmed. Different contact materials (Ag, Au, Ir, Pd, Pt, Zn) show similar contact currents and voltage features. Different metal contacts of Pt and Zn electrodes show phenomena that depend mainly on the negative electrode metal. Our study confirms that the so-called "initial arc" phenomenon has a close relation with arc ignition, but is independent of arc phenomena.