A varistorvoltage dependent resistor vdr is a component which has a voltage current characteristics that is very much similar to that of a diode. Penlington university of northumbria, newcastle upon tyne, uk metal oxide varistors are znobased ceramic devices having highly nonlinear currentvoltage characteristics similar to those of the back to back zener diodes. Specifications may be changed at any time without prior notice. Thus, mov manufacturers are unable to tap the market for low voltages. Comparative study of metal oxide varistors movs for failure mode identification. Jvr10n561k datasheet pdf pinout metal oxide varistor. Pdf on the use of metal oxide varistors as a snubber. A surge in excess of the specified withstanding surge current may cause short circuits or package rupture with expulsion of material.
Littelfuse metal oxide varistors mouser electronics. Aug 28, 2007 metal oxide varistor mov are voltage dependent symmetrical resistors intended to protect equipment from transient voltages resulting from lightning strikes. Varistors are in stock and ship sameday at mouser electronics from industry leading manufacturers. Varistor symbol and applications metal oxide varistor. Metal oxide varistor mov, basics, working, specifications. Jvr10n561k datasheet, jvr10n561k pdf, jvr10n561k pinout, equivalent, replacement metal oxide varistor rfe, schematic, circuit, manual. California 91605 phone 818 7658300 toll free 800 8277422 fax 818 7652387 d2 rga varistor varistors are voltage dependent, nonlinear devices which have an electrical behavior similar to backtoback zener diodes. Degradation of metal oxide varistors caused by electrical stresses. Metal oxide varistors high energy disc varistor series metal oxide disc varistors features the disc varistor series of transient surge suppressors are industrial provided in disc form for unique packing by highenergy disc varistors movs intended for special applications customer requiring unique electrical contact or packaging methods. Vdr metal oxide varistors standard additional resources ordering information the varistors are available in a number of packaging options.
Metal oxide varistor tvr type pdf free download docplayer. This component is located near the ac supply input and before the bridge rectifier. Electronics tutorial about the varistor and metal oxide varistor or mov which is used in power electronics circuits for protection against transients. On the use of metal oxide varistors as a snubber circuit in solidstate breakers.
Jun 08, 2015 the burning issue of metal oxide varistors and how to stop thermal runaway. The mov07dxxxk series of 7 mm radial leaded varistor devices protects against overvoltage transients such as lightning, power contact and power induction. Mov metal oxide varistors testing all about circuits. A varistor is an electronic component with an electrical resistance that varies with the applied. To assure our customers quality harris metal oxide varistors and other products and services at international standards, galco maintains iso90012000 certification. Make us your source for harris metal oxide varistors and other products. Investigation of various models for metal oxide varistors springerlink. Metal oxide varistor electronics repair and technology news. For example, a potentiometer is a metal oxide varistor that provides protection against potential power surges and excessive voltage. Pdf metal oxide varistors movs are the essence of surge protection devices and have dominated the market with their highly. Metal oxide varistors when to use varistor vs tvs diode.
Many industry manufacturers, including current technology, integrate various sizes of radial or straptype movs into their products. Tama is supplying transient voltage surge suppressors, metal oxide varistor, nv series. They use these mov metal oxide varistors for light ballast circuits they are these very small and the color is blue with the circuit turned off, how do you test and check mov varistor compoents. Measuring the energy handling capability of the metal oxide varistors m. Metal oxide varistor mov technology is the most prevalent technology utilized in electrical transient protection products today.
The name is a portmanteau of variable resistor, which is misleading since it is not continuously uservariable like a potentiometer or rheostat and is capacitor rather than resistor at low field. Users should verify actual device performance in their specific applications. It is generally manufactured from a material such as zinc oxide, zno, although another material that is used is silicon carbide, sic and this provides similar properties. Sep 22, 2015 the operation of metal oxide varistor and silicon carbide varistor are very similar. Electronic component search and free download site. The most famous type of varistor is metal oxide varistor mov, which is also called as zno varistor. The name varistor is a portmanteau of varying resistor. The za series of transient voltage surge suppressors are radiallead varistors movs designed for use in the protection of low and medium voltage circuits and systems. Large withstanding surge current capability 0 radial. Pdf degradation of metal oxide varistors caused by electrical. The metal oxide varistors offer a choice of varistor voltages from 18 v to 1800 v and vrms voltages from 11 v to 1100 v. Varistor voltage clamping characteristics can be defined at various test levels. 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.
Pdf comparative study of metal oxide varistors movs. The main difference between a silicon carbide varistor and a metal oxide varistor is the amount of leakage current. The burning issue of metal oxide varistors and how to stop. Pdf reliability evaluation of metal oxide varistors for.
Zenamic features large surge current handling ability and transient overvoltage handling. Measuring the energy handling capability of metal oxide. Normally, the mov has very high electrical resistance. Analysis of metal oxide varistor arresters for protection of multiconductor transmission lines using unconditionallystable cranknicolson fdtd. Reliability evaluation of metal oxide varistors for maintenance scheduling. The tinned copper alloy terminals are suitable for snpb and leadfree wave and reflow solder. Metal oxide varistor datasheet pdf, equivalent, schematic,datasheets, transistor, cross reference, pdf download, free search site, pinout. Specifications are subject to change without notice. They are primarily protective devices to dump the current in excessive over voltage events and so save the circuit board or end equipment. The objective of this paper is to analyze the ageing of metal oxide varistors mov due to surges by the changes of the nonlinear behavior. Variable resistors, such as the potentiometer and the rheostat, have ohmic characteristics. Metal oxide varistors consist of approximately 90% zinc oxide as a ceramic base material plus other filler materials for the. Within the useful varistor voltage range, the voltagecurrent relationship is approximated by the expression.
Metal oxide varistors, more commonly known as movs are devices that provide excellent transient voltage suppression. Metal oxide varistor devices are typically utilized because they are easier to build and control a majority of extreme power and voltage surges. Completely uptodate, this is the first comprehensive monograph on metal oxide varistors with a focus on microstructure, conduction mechanisms, device failures, ageing, additive impacts and future varistor systems. If lightning strikes a nearby power line, the high voltage causes the mov to become a shunt, preventing the. The devices have a high current handling, high energy absorption. The surge arrester installed in the field is submitted. Thinking tvr varistor the first brand of mov shipments. The surfaces of the intercrystalline fracture follow the znograin boundaries. Zinc oxide varistor tvr seriesproductsvetng thinking ltd. The metal oxide varistors offer a choice of varistor voltages from 18 v to 820 v and v rms voltages from 11 v to 510 v. Pdf comparative study of metal oxide varistors movs for.
Movs or metal oxide varistors are a very popular product and widely used. Select the right varistors for overvoltage circuit. Mov14dxxxk series metal oxide varistor rohs directive 200295ec jan. Rga series zinc oxide varistors are nonlinear resistors, consisting mainly of zinc oxide and several kinds of. The itmov varistor differs from the tmov varistor by the inclusion of a third.
A metal oxide varistor starts conducting current at rated voltage and it stops the conduction if the applied voltage is below the threshold value. They are mainly used in the protective circuits of voltage sensitive electronic devices. They exhibit a highly nonlinear currentvoltage relation with a 5%. We also have an extensive resource database for sourcing and crossreferencing parts. They are used to protect vulnerable electronic circuits and components from overvoltage conditions that can cause damage. Zinc oxide varistors are electronic ceramic materials whose electrical behavior is dominated by grainboundary interface states. The use of mov not only reduces the chance of electrical damage buut also improves equipment reliability. They are a type of nonlinear device that feature similar characteristics to zener diodes. A metal oxide varistor mov is an electronic device that protects an appliances power supply from voltage spikes and surges in the ac power line. Metaloxide varistors movs tmov and itmov varistor series.
Zenamic is the registered trademark for our oxidized metal varistors. Varistors, also called metal oxide varistors movs, are used to protect sensitive circuits from a. The power so developed must be within the specifications shown on the. I put my ohm meter across a mov varistor and i got no ohm resistance reading it just said o. Varistor and the metal oxide varistor tutorial electronicstutorials. Global metal oxide varistors market is segmented by type into surface mount and disc. A test current of 1ma dc is typically used to determine varistor voltage classification type.
The power so developed must be within the speci cations shown on the device ratings and speci cations table for the speci c. Pdf the degradation of zinc oxide elements under under ac or dc operating voltage and impulse currents is described. Global metal oxide varistor market is segmented by application into electronic discharge esd and overvoltage protection. Metaloxide varistors movs ciii varistor series littelfuse. Metal oxide varistor tvr series, for surge protection, professional manufacturer, high quality, from china original factory. Bulk on tape and reel on tape in ammopack fanfold the basic ordering code for each option is given in tables titled varistors on tape on reel, varistors on tape in ammopack and varistors in bulk.
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