A multipole arrangement of a busbar and connector system for supplying the power for at least two electrical switching devices located alongside one another on a longitudinally extending support element, wherein the busbars system comprises - flat bars arranged in parallel alongside one another in a multi-walled box section of an insulating material, - at least one retaining element that can be applied to the support element, serving to retain the flat bars, - wherein the at least one retaining element is configured so that the flat bars are situated parallel to the longitudinally extending support element, - and the flat bars have a longitudinal extension, which corresponds to at least the sum of the widths of a plurality of switching devices (50, 52) mountable side by side on the support element, - and the flat bars are retained so that their narrow sides are freely accessible from the outside, and the connector system comprises - electrical conductor connections (19A, 19B), which serve to carry the potential from the flat bars to the switching devices (50, 52), - wherein the conductor connections (19A, 19B) are attachable from the outside to the narrow sides of the flat bars, - wherein the conductor connections (19A, 19B) in each case are housed in a housing (12A3, 12B, 12C, 12X) of an insulating material forming a plug-in module (12A3, 12B, 12C, 12X), and - the input contacts of the conductor connections (19A, 19B) are configured for making contact in the flat rails and access contacts (15', 15") of the conductor connections (19A, 19B) for making contact with the switching devices as rigid plug-in contacts (16, 15', 15"), characterised in that two retaining elements are present lying in parallel and perpendicular to the longitudinal extension of the support element and perpendicular to the longitudinal extension of the busbars system, and they are configured so that they can be slid or clipped onto the support element. - flat bars arranged in parallel alongside one another in a multi-walled box section of an insulating material, - at least one retaining element that can be applied to the support element, serving to retain the flat bars, - wherein the at least one retaining element is configured so that the flat bars are situated parallel to the longitudinally extending support element, - and the flat bars have a longitudinal extension, which corresponds to at least the sum of the widths of a plurality of switching devices (50, 52) mountable side by side on the support element, - and the flat bars are retained so that their narrow sides are freely accessible from the outside, - electrical conductor connections (19A, 19B), which serve to carry the potential from the flat bars to the switching devices (50, 52), - wherein the conductor connections (19A, 19B) are attachable from the outside to the narrow sides of the flat bars, - wherein the conductor connections (19A, 19B) in each case are housed in a housing (12A3, 12B, 12C, 12X) of an insulating material forming a plug-in module (12A3, 12B, 12C, 12X), and - the input contacts of the conductor connections (19A, 19B) are configured for making contact in the flat rails and access contacts (15', 15") of the conductor connections (19A, 19B) for making contact with the switching devices as rigid plug-in contacts (16, 15', 15"),