Metal Oxide Varistor

The Metal Oxide Varistor (MOV) is a voltage dependent resistor in which the resistance material is a metallic oxide (zinc oxide (ZnO)) pressed into a ceramic like material. Metal oxide varistors are the most common type of voltage clamping device and are available for use at a wide range of voltages and currents. Both MOV’s and normal varistors(Silicon Carbide) are capable of conducting current at specific voltage and stops when the voltage falls below a threshold voltage. However the difference between the two is that MOV’s leakage current is very small and its speed of operation in clamping transient is much faster than the normal varistor.

Source: electronics-tutorials.ws

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