Fault current protection unit for protection against fault currents in a voltage supply mains, has first protection conductor connected to mains filter and second protection conductor for contact protection of load

摘要

The fault current protection unit is designed with a fault current identification facility (22) which includes a summation current transformer (20). So that the phase conductors (L1,L2,L3), the neutral conductor (N) and a first protection conductor (FE) of a mains protection conductor (PE) of the voltage supply mains (10) are connected to the primary circuit of the summation current transformer (20). The first protection conductor (FE) of the connection, is connected to a mains filter (40), producing capacitive bled off currents in the voltage supply mains, assigned to the electric user eg. a motor (12). Also a second protection conductor (PE') for a contact protection of the user (12), by the by-passing of the fault current protection unit (14) with the mains protection conductor (Pe).