A shield apparatus and a resultant circuit interrupter are disclosed, wherein the shield apparatus includes a shield apparatus base and a protection apparatus, with the protection apparatus including a shield that helps to direct an electrical arc along a flow path through a number of passages and that will help to enable dissipation of the arc and the plasma generated thereby. The shield apparatus is mountable to a portion of the housing of the circuit interrupter within its interior, and the shield is situated adjacent at least a first passage.

A shield apparatus and a resultant circuit interrupter are disclosed, wherein the shield apparatus includes a shield apparatus base and a protection apparatus, with the protection apparatus including a shield that helps to direct an electrical arc along a flow path through a number of passages and that will help to enable dissipation of the arc and the plasma generated thereby. The shield apparatus is mountable to a portion of the housing of the circuit interrupter within its interior, and the shield is situated adjacent at least a first passage.

A method and test device for testing protection relays, the test device having a signal generator. The signal generator supplies a signal as pulses having pause times, which alternate over time. Signal level is reduced during the pause times and at least one pulse has an amplitude at least higher than one of the preceding pulses. A supply voltage is supplied by an accumulator providing electric energy for generating the pulses. Via the accumulator, a greater mobility and flexibility is ensured, and fuel-fed power units or emergency power units may be omitted. In order to reduce the load (average energy) on the accumulator, the signal generator emits the signal as pulses having pause times. The pulse amplitudes may have an increasing trend to reach a switching threshold. This allows the use of smaller and more compact, which is important for a portable test device.

A method and test device for testing protection relays, the test device having a signal generator. The signal generator supplies a signal as pulses having pause times, which alternate over time. Signal level is reduced during the pause times and at least one pulse has an amplitude at least higher than one of the preceding pulses. A supply voltage is supplied by an accumulator providing electric energy for generating the pulses. Via the accumulator, a greater mobility and flexibility is ensured, and fuel-fed power units or emergency power units may be omitted. In order to reduce the load (average energy) on the accumulator, the signal generator emits the signal as pulses having pause times. The pulse amplitudes may have an increasing trend to reach a switching threshold. This allows the use of smaller and more compact, which is important for a portable test device.

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.