GRADING MEANS FOR HIGH VOLTAGE METAL ENCLOSED GAS INSULATED SURGE ARRESTERS

摘要

5D-5696 GRADING MEANS FOR HIGH VOLTAGE METAL ENCLOSED GAS INSULATED SURGE ARRESTERS Capacitance grading is provided within gas insulated lightning arresters containing stacked zinc oxide varistors by means of a grading ring electrically connected to the line terminal or, for arresters of the higher voltage ratings, by means of a plurality of telescoping external electrostatic shields. The shields are arranged so that the degree of overlap between sequential shields decreases from the line end to the ground end of the varistor stacks. The capacitance grading is provided by the degree of overlap between the sequential shields and the ratio of the radii of the overlapping shields.