Use and Properties of Extruded High-Strength Aluminum for Electric Bus Conductors [includes discussion]

Extruded and heat-treated high-strength aluminum bus conductors offered by the major suppliers of electric busses were found to be similar in all respects. Except for electrical conductivity, the new conductor alloy is similar to the extruded and heat-treated architectural alloy designated as 6063-T6 by the Aluminum Association. Current-carrying tests were made on one of the available alloys to establish 60-cycle current ratings for this new bus material. The results of these tests are applicable to the other high-strength bus materials. Short-circuit tests were also made to determine adequate spacing between bus supports for various 3-phase fault currents and also to compare the relative strengths of busses made of this new alloy and copper.