CIRCUIT FOR CAPACITIVELY COUPLING DATA COMMUNICATION EQUIPMENT TO A POWER LINE AND A COUPLING UNIT WITH A COUPLING CIRCUIT

摘要

A series connection (9) consisting of a miniature fuse (15), a coupling condenser (17) and a first lightning arrester (19) with a parallel drain coil (20) is arranged between the phase (T) and the reference potential (5) of the power line (1). Data communication equipment (3) can be coupled to the drain coil (20). The electric characteristic values of the miniature fuse and the lightning arrester are adjusted in such a way that the miniature fuse is quickly and safely triggered by the lightning arrester when a short-circuit current (Ik) is building up slowly in the case of a failure of the coupling condenser.