Investigation of Conductor Packages and Contact Geometries for Stranded Copper Wires

For electrical connections, stranded copper wires are commonly used. Solid wires form one contact resistance between the conductor and the busbar. In contrast, stranded wires additionally give rise to inner cross resistances between the individual strands. The total resistance of stranded wires depends on the shape of the conductor package, which influences the number of vertical and horizontal strands. In this paper, the conductor package of stranded wires is investigated with analytical methods. A model for calculating total resistances is presented. Measurements with different conductor packages are carried out and compared to calculated values. For wide conductor packages, the lowest resistances are found. In addition, the impact of contact geometries is examined; beads with low contact radii tend to show the lowest resistances.