Self-healing wound capacitor - with outer metal foils separated by fusible insulation produces short circuit by major burn-out

摘要

A wound capacitor of the self-healing type has the capacitor body encased in a first metal layer which is electrically connected to the lead to one set of plates. An insulating layer, pref. of polypropylene, follows; this melts or is plastically deformed by any excessive temp. rise. A second metal layer is electrically connected to the lead to the other set of plates. In case of a major burn out inside the capacitor the temp. rise displaces the insulating layer and causes a short-circuit between the metal layes so that the fuse for the capacitor blows and severs the connection from the mains as prescribed by the VDE regulations.