A low-voltage protective device includes: at least one outer conductor path from an outer conductor power terminal of the low-voltage protective device to an outer conductor load terminal of the low-voltage protective device; a neutral conductor path from a neutral conductor terminal of the low-voltage protective device to a neutral conductor load terminal of the low-voltage protective device; a mechanical bypass switch arranged in the outer conductor path; a first semiconductor circuit arrangement connected in parallel to the mechanical bypass switch, the first semiconductor circuit arrangement having at least one power semiconductor, such as an IGBT, with a control terminal, such as a gate terminal; an electronic control unit; a current-measurement arrangement arranged in the outer conductor path, connected to the electronic control unit of the protective device; and at least one voltage measurement arrangement for detecting a Miller effect-induced voltage spike at the at least one power semiconductor.