Zinc oxide varistor having reduced edge current density

摘要

A zinc oxide varistor disc is provided with one or more circumferential recesses in its rim to reduce the current density at the edges of the electrodes on the opposed disc faces, which electrodes are of a lesser diameter than the varistor disc. It has been discovered that optimum results are achieved when the diameter at the bottom of the recess is somewhat less than the diameter of the electrodes.