A protection apparatus for protecting a surge protection device has a current-diverting circuit connectable between a surge protection device and a power distribution circuit, the current-diverting circuit comprising a main switch, a current sensor configured to generate a detection signal in response to detecting a current in the current-diverting circuit, and a controller configured to test a tripping condition and to open the main switch in response thereto, wherein the tripping condition is configured to avoid opening the main switch in response to the surge current. The current-diverting circuit further has a fuse element connected in series with the main switch, wherein the fuse element is rated to withstand the surge current and to melt into an open state in response to a high intensity current, in an urgent disconnection delay shorter than a time required by the controller to test the tripping condition.

A protection apparatus for protecting a surge protection device has a current-diverting circuit connectable between a surge protection device and a power distribution circuit, the current-diverting circuit comprising a main switch, a current sensor configured to generate a detection signal in response to detecting a current in the current-diverting circuit, and a controller configured to test a tripping condition and to open the main switch in response thereto, wherein the tripping condition is configured to avoid opening the main switch in response to the surge current. The current-diverting circuit further has a fuse element connected in series with the main switch, wherein the fuse element is rated to withstand the surge current and to melt into an open state in response to a high intensity current, in an urgent disconnection delay shorter than a time required by the controller to test the tripping condition.

A circuit breaker protecting an electric low-voltage circuit includes a housing with grid-side and load-side connections and a series circuit of a mechanical isolating contact unit on the grid side and an electronic interruption unit on the load side. The mechanical isolating contact unit has a handle opening and closing contacts. A current sensor unit is disposed in a conductor between the isolating contact unit and the interruption unit, for ascertaining a current level of the low-voltage circuit. A control unit is connected to the current sensor unit, electronic interruption unit, and mechanical isolating contact unit. When current and/or current/time thresholds are exceeded, prevention of a current flow in the low-voltage circuit is initiated. A power supply unit supplying energy to the circuit breaker is connected to conductors of the low-voltage circuit between the isolating contact unit and the interruption unit.

A box core module, a plug module, and a surge protective device (SPD) are provided. The plug module includes a housing, bottom plates, a plurality of box core modules with an independent tripping mechanism, a first pin electrode, and a second pin electrode. The plurality of box core modules are vertically arranged on a side of the bottom plates in a side-by-side or opposite manner, and the plurality of box core modules are connected by an internal connection electrode to form a series and/or parallel combined line. The combined line is led out through the first pin electrode and the second pin electrode. The plug module is combined with a base. A modularized multi-form assembly-type SPD is provided. Mutual conversion between a high working voltage of the SPD and a large lightning strike through-current is achieved when the same voltage-limiting element is used and an overall tripping mode remains unchanged.

A box core module, a plug module, and a surge protective device (SPD) are provided. The plug module includes a housing, bottom plates, a plurality of box core modules with an independent tripping mechanism, a first pin electrode, and a second pin electrode. The plurality of box core modules are vertically arranged on a side of the bottom plates in a side-by-side or opposite manner, and the plurality of box core modules are connected by an internal connection electrode to form a series and/or parallel combined line. The combined line is led out through the first pin electrode and the second pin electrode. The plug module is combined with a base. A modularized multi-form assembly-type SPD is provided. Mutual conversion between a high working voltage of the SPD and a large lightning strike through-current is achieved when the same voltage-limiting element is used and an overall tripping mode remains unchanged.