Voltage non-linear resistor and its manufacture

Abstract

A voltage non-linear resistor excellent in varistor voltage characteristics, lightning discharge current withstanding capability and life performance against applied voltage comprises a disc-like voltage non-linear element and a thin insulating covering layer integrally provided on the side surface of said element. In the resistor according to the invention, said element comprises zinc oxides as main ingredient, 0.1-2.0% bismuth oxides, as Bi.sub.2 O.sub.3, 0.1-2.0% cobalt oxides, as CO.sub.2 O.sub.3, 0.1-2.0% manganese oxides, as MnO.sub.2, 0.1-2.0% antimony oxides, as Sb.sub.2 O.sub.3, 0.1-2.0% chromium oxides, as Cr.sub.2 O.sub.3, 0.1-2.0% nickel oxides, as NiO, 0.001-0.05% aluminum oxides, as Al.sub.2 O.sub.3, 0.005-0.1% boron oxides, as B.sub.2 O.sub.3, 0.001-0.05% silver oxides, as Ag.sub.2 O and 7-11% silicon oxides, as SiO.sub.2, and said layer comprises 45-60% silicon oxides, as SiO.sub.2, 30-50% zinc oxides, as ZnO, 1-5% bismuth oxides, as Bi.sub.2 O.sub.3 and antimony oxides for the remainder (% stands for mole %). The resistor of the invention preferably further comprises a thin glassy layer superimposed on the insulating covering layer. The resistors are advantageously adaptable to arrestors, surge absorbers used in high voltage power systems.

Dependencies are inferred from the claim text.