Metal Oxide Varistors

The metal oxide varistor (MOV) is a nonlinear resistive element and is composed of
mainly from zinc oxide (ZnO), which has a very high surge voltage capacity and
has a large nonlinear coefficient.
Below the threshold voltage (“Clamping Voltage”), their resistance is very
high, almost no current flows.
Above the threshold voltage, the resistance decreases sharply.
This allows large currents to be discharged.
Due to this property, the varistor can be used as a protective component in
electronic and electrical equipment abnormal overvoltages and
Derive lightning shocks.