Abstract: A line coupler is provided having a bus line piece, at least one transformer, two electrically shielded housings and a coupling site. The transformer is equipped with two primary and two secondary winding terminals. The two primary winding terminals are connected to the pair of coupling elements located at the coupling site. Each coupling element is connected to one of the bus line wires contained in the bus line piece. The secondary winding terminals are connected to branch line wires, which are brought out from the secondary electrical shielded housing. The two electrically shielded housings are electrically connected to each other by two connectors, these connectors also allow the two housings to be releasably connected.