Material Effect on Glowing Contact Properties

Properties of glowing connections for a variety of electrically conductive materials are presented. The properties investigated include voltage waveforms, rms voltage with current and the propensity to initiate glowing. This was done using materials that may be used in residential electrical wiring. The materials and combinations of materials investigated were copper, brass, phosphorous bronze, steel, and stainless steel. It is found that material type has a pronounced effect on the voltage wave-shape of the glowing contact and the associated rms voltage. It is also shown that the number of make/break operations to get the connection glowing is greatly influenced by the material with steel materials being the easiest to initiate glowing. Waveforms and voltage values over a current range of 0.5 A_rms to 11 A_rms are presented and there is discussion on the influence of oxide resistivity and material parameters on glow voltage.