ELECTRICAL INSULATORS, MATERIALS AND EQUIPMENT

摘要

An elongate high voltage insulator (2) is formed of a rod or tube (4) of insulating material, with a pair of electrodes (6) spaced apart longitudinally thereof. At least part, and preferably the whole of the outer surface of the insulating material (4) is covered by a layer of material (8) comprising a particulate filler of varistor powder in a matrix having a switching electrical stress-controlling characteristic that is in electrical contact with each of the electrodes (6). The insulator core (4) may be made of porcelain, and the stress-controlling material (8) may comprise zinc oxide.