DIRECTIONALLY VENTED UNDERGROUND DISTRIBUTION SURGE ARRESTER

摘要

The invention is directed to the provision ofan external shield about the periphery of the housing(102) of a surge arrester (100) containing one or morearrester devices (116) to provide an expansion limitingdevice which permits the housing to expand to a degreenecessary to permit the expulsion of arc-generated gaseswithin the housing while limiting the total expansion toa level below the elastic limit of the housing toprevent its destruction and permit its recovery afterthe gases have been dissipated. The shield may be madeof metal, elastomeric materials, reinforced elastomericmaterials or plastic, and the shield may be supportedabout the housing by an external strap (144) of metal,plastic or elastomeric materials or may be supported bya plurality of fins (142) arranged along the peripheryof the housing and engaging an edge of the shield on itsinternal surface.