A device for protecting an electrical system against surge voltages, comprising one or more protection components (10) provided with means (20) for connecting same with said system and means (30) for disconnecting said component (10) from said system, characterised in that it comprises arc-breaking means (40) for preventing the generation of electric arcs between the disconnection means (30) and the connection means (20) when the disconnection means (30) is in an open state, wherein said arc-breaking means (40) consist of an insulating flap (41) capable of moving within the gap (11) and comprising a central portion (42) to be positioned between the disconnection (30) and connection (20) means, and side portions (43) shaped in such a way as to prevent the electric arc from bypassing the arc-breaking means (40). Electrical surge voltage protection devices are also described.