Method of making a stable high voltage DC varistor

摘要

A high voltage varistor for DC operation is manufactured by applying a glass collar to the perimeter of a sintered zinc oxide disc and heat treated between about 750 DEG C. and 400 DEG C. for several cycles in air. After heat treating, an organic resin or ceramic coating is applied to the glass collar to further insulate the varistor for high voltage application.