Switching apparatus protected against short circuit currents

A protective switching apparatus comprising:

• a first connection terminal adapted to be connected to a current line of an electrical network, so as to have an electrical potential;
• a second connection terminal adapted to be connected to a load which is conceived so as to be traversed by a nominal current;
• a first switch which is controlled by an electromagnet and which is adapted for establishing and interrupting frequently said nominal current, said first switch comprising a first input power terminal connected to said first connection terminal, and an output power terminal;
• a second switch with automatic opening having properties for limiting fault currents, so as to provide protection of said line and to prevent dammage of the first switch, said second switch having a second input power terminal connected to said first output terminal, a second output power terminal connected to said second connection terminal, first and second contacts respectively connected to said second input power terminal and to said second output power terminal and means acting on at least one of said contacts when a fault current is occuring, for causing the second switch to pass from a closed position to an open position wherein a first arc path having a first resistance is formed between said first and second contacts;
• a transfer electrode located in the vicinity of said first and second contacts and isolated therefrom, said transfer electrode being connected to said first connection terminal by a conductor placed in parallel across the first switch;
• and a first mobile isolating piece adapted to be propelled between said first and second contacts during said automatic opening, so as to form with said transfer electrode and said second contact a second arc path having a second resistance less than the said first resistance.