Metal Oxide Varistor

The metal oxide varistor or mov is a voltage dependent nonlinear device that provides excellent transient voltage suppression.

Metal oxide varistor.

Metal oxide varistors and multi layered varistors. Once the voltage across the varistor increases the resistance will be decreased. Metal oxide varistor is a voltage dependent resistor. They are composed primarily of z n o with small additions of other metal oxides such as bismuth cobalt magnese and others.

Metal oxide varistor mov to overcome the limitations of semiconductor based varistors like silicon carbide varistors the metal oxide varistors mov have been developed. It is also a non linear device and provides very good transient voltage surge protection. Metal oxide varistors littelfuse inc. A metal oxide varistor or mov is the blue or orange colored circular component that you can commonly spot on the ac input side of any power supply circuit the metal oxide varistor can be considered as another type of variable resistor that can vary its resistance based on the applied voltage across it.

The term mov or metal oxide varistor is a variable resistor. But not like a potentiometer its resistance will change automatically depending on its voltage. Metal oxide varistors consist of approximately 90 zinc oxide as a ceramic base material plus other filler materials for the formation of junctions. There is no polarity for these leads and hence can be connected in both directions.

Mov is the most commonly used type of varistor. It is called so as the component is made from a mixture of zinc oxide and other metal oxides like cobalt manganese and so on and is kept intact between two electrodes which are basically metal plates. Metal oxide varistors are also connected in series to supply high voltage ratings. The metal oxide varistor or mov for short is a voltage dependant resistor in which the resistance material is a metallic oxide primarily zinc oxide zno pressed into a ceramic like material.

The most common modern type of varistor is the metal oxide varistor mov. The metal oxide varistor is designed to protect various types of electronic devices and semiconductor elements from switching and induced lightning surges. Basic operation electrical characteristics and applications will be discussed. Metal oxide varistor basics.

There will also be a presentation of the different mov products littlefuse brings to the marketplace. When a high current passes through a mov its resistance value decreases and acts as a short. The boundary between each grain and a neighbor forms a diode junction which allows. This type contains a ceramic mass of zinc oxide grains in a matrix of other metal oxides such as small amounts of bismuth cobalt manganese oxides sandwiched between two metal plates which constitute the electrodes of the device.

Metal oxide varistors are similar to resistors and has only two leads. This tutorial will provide an introduction to metal oxide varistors and mov product offerings from littelfuse.