In this modular control assembly, individual bus conductor segments are integrated in modular, alignable housing blocks. The bus conductor segments have strip conductors on the upper and lower surfaces thereof. The bus conductor segments of mutually adjoining housing blocks are electrically connected by separating slide contact members. The contact members comprise a closed housing containing upper and lower contact springs for engaging the strip conductors of the bus conductor segment. The slide contact members can be pushed between an extended position in which they grasp the mutually facing ends of bus conductor segments (8) of neighboring housing blocks and a retracted position in which only one bus conductor segment is covered by the slide contact member.