Abstract: A busbar (110, 120) for luminaires or other electrical devices has a plurality of busbar sections which can be connected to one another and which each have a plurality of lines (111, 121), running in a longitudinal direction, for power supply and/or signal transmission, which lines (111, 121) are arranged in grooves (113, 123), open towards a contacting side, of a line-receiving structure (112, 122) consisting of an insulating material. Electrical contacts (50) are arranged in the connecting region of two successive busbar sections, to which contacts (50) in each case the ends of two lines (111, 121) to be connected to one another can be connected and which contacts (50) form a contacting surface (51) accessible from the contacting side, wherein at least one of the electrical contacts (50) is removable in order to interrupt the connection of the corresponding line (111, 121) between two successive busbar sections.