Abstract: A device is for protecting against fault currents, even with frequencies of fault currents higher than 1 kHz. Additionally, it is for protecting against fires to dependably protect people. The converting core of a total current converter mounted upstream of a triggering arrangement, in a releasing circuit, is designed for detecting fault currents of different types. Further, an RC circuit is mounted parallel to the triggering arrangement, on the input side.

Abstract: Two detection systems are provided for a protective device, in particular an FI protective device, having a core balance transformer whose secondary winding is followed by a tripping relay for operating a switching mechanism, which switches a conductor network. In this case, a first detection system carries out the tripping function for fault currents at a fault current frequency below a changeover frequency. The second detection system carries out the tripping function for fault currents above the changeover frequency. The changeover frequency is in this case preferably not less than 1 kHz.