The Effect of Various Atmospheric Temperature on the Contact Resistance of Sliding Contact on Silver Coating Slip Ring and Silver Graphite Brush

The performance and reliability of electric motors, electric devices and electrical connections depend on the quality of their materials. One suitable material that is used in the electrical field is silver, because of its high electrical and thermal conductivities. Laboratory studies were made of the effect of temperature changes on a silver coated slip ring and silver graphite brushes. Over the past months, a study have been made on sliding contact using copper ring and natural graphite brush, as compare the copper ring and natural graphite brush, and silver coating ring and silver graphite brush. The contact voltage drop of the copper ring and natural graphite brush increased with the sliding time. However, the contact voltage drop of the silver coated ring and silver graphite brush had little change. In this study we focused on the contact voltage drop, surface film and brush wear at low temperature range -15 to 0°C under using silver material. The main rule of low current sliding contact should combine high wear resistance, low friction with stable contact voltage drop. To meet this requirement we realized that at 70 wt% silver brush, we could reach to this requirement.