The formula for current carrying capacity of a busbar, when busbar size is given: For copper busbar: Iccc = 1. 8*busbar width*bus bar. The calculator determines the correct busbar dimensions, verifies temperature rise, calculates voltage drop, and checks short-circuit withstand capacity. “ Replaced three separate apps with Elec-Mate. Certs, quotes, and scheduling all in one place. The current rating is calculated from the conductor cross-sectional area, material (copper or aluminium), and maximum. Bus bars are the essential components in the electrical distribution systems (EDB) serving as primary conductors that carry current between 1). Note = Ampacity based on typical DIN 43671 / IEC.