A contact and busbar assembly forms a bus system on electronics housings arranged in an array direction. Each housing includes a circuit board. The contact and busbar assembly includes multiple bus plugs having first connecting contacts for electrically contacting the circuit boards and second connecting contacts in the form of socket contacts for electrically contacting power rail strips. A plurality of power rail strips electrically connects the second connecting contacts of adjacent electronics housings. A first power rail strip electrically connects the bus plugs of two directly adjacent electronics housings and a second power rail strip of greater length electrically connects two spaced electronics housings. An electronics housing assembly is provided having multiple electronics housings arranged against one another in the array direction and a contact and busbar assembly as set forth above. A method for removing or replacing an electronics housing arranged between two adjacent electronics housings of such an electronics housing assembly is also provided.