Post Bridge Phenomena in Electrical Contacts at the Initial Stage

摘要

Consecutive stages of contact opening are described by the mathematical model. It includes phenomena in separating contacts before melting point, appearance, evolution and rupture of liquid metal bridge, the arc ignition and spreading in bridge metallic vapours until transformation of metallic arc phase into gaseous one.rnThe calculation of lifetime and energy of each stage, contact voltage, temperature and other parameters are compared with experimental data obtained by Prof. T.Takagi and Prof. R.Haug. It is shown that arc duration depends on opening velocity, contact scale roughness, energy and length of liquid bridge.