Metal Oxide varistor is generally used in parallel in the circuit. When the voltage of varistor across changes sharply, varistor short-circuits and cutoff current fuse, which plays a protective role. Varistors are often used in circuits for power supply overvoltage protection and voltage stabilization.

Construction:

Metal oxide varistors are typically constructed from zinc oxide and combined with small additions of other metal oxides such as cobalt, magnese or bismuth. These materials are sintered into ceramic casings during manufacture. Although MOVs are available in different formats, they are most commonly radial leaded discs,also surface mount encapsulation is available.

Applications:

• Suppression of lightning and other high levels of transient energy

• Low voltage power supplies in DC circuits

• Low voltage power supply in automotive applications

• Protection from internal transients within capacitor discharges, relay switching and inductive load switching