Abstract: A protective device against fault currents includes a triggering arrangement for performing at least the functions of detecting a fault current and/or triggering power-down of the network to be protected. The triggering arrangement, outside the most strict quartic curve (A), corresponds to the protection of persons in case of indirect contact, and below the triggering quartic curve (B), corresponds to protection against fire. The triggering quartic curve (B) satisfies the relationship: ILimit(f)/I&Dgr;n=F(f)=B=const., wherein ILimit(f)=WFire/UNetwork.

Abstract: A residual current device includes a residual current tripping circuit for actuating a release, and an additional monitoring device for checking the release, in which case a device is provided for electrically decoupling the residual current tripping circuit from the monitoring device.

Abstract: A socket-outlet, in which, only in response to preselected loads, voltage from the supply-side is connected through by a switching device to the load side. A voltage-supplied measuring device has a D.C. testing circuit and an A.C. testing circuit. Both testing circuits attempt to drive measuring currents across a connected load. The A.C. testing circuit operates at higher frequencies than the power-line frequency. An evaluation circuit is designed, on the basis of preselected criteria and on the basis of measuring values, in logical AND-connection, to determine whether switching contacts of the switching device should be closed.

Abstract: Connector, in particular a plug-in connector for TT and TN networks, in which an electronic monitoring and control unit supplied with a voltage switches through conductors or releases the connection, by means of a switching device, from the supply side to the load side of the connector as a function of information or measured data. Potential-measuring devices measure conductor potentials continuously or at regular intervals on the supply side and/or on the load side, and the switch is activated if the result falls short of or exceeds specific limits. Also,the electronic monitoring and control unit is designed to generate a signal if the connection is briefly released or established a certain number of times within a predetermined period;the conductors to be switched through are monitored by a fault current detecting device which acts upon the switching device; andinformation and/or command data are present at a bus interface.