Abstract: An electrical capacitor composed of: a coil composed of metal coatings and having opposed end faces; contact layers applied to the end faces of the coil; a casing enclosing the coil; and a conductor structure including a tearable interrupter conductor connecting the contact layers to external capacitor terminals, the conductor being disposed to rupture, and thus break the connection between the capacitor and one external terminal, in response to enlargement of the coil due to a fault, and the casing being disposed directly against the coil and adhering to the interrupter conductor in such a manner that the casing ruptures in response to such enlargement of the coil and promotes rupture of the interrupter conductor.