Help identifying a varistor electrical engineering stack. Vdr metal oxide varistors standard additional resources ordering information the varistors are available in a number of packaging options. Pdf on the use of metal oxide varistors as a snubber. The key to explaining metaloxide varistor operation lies in understanding the.
Inorganic and bioinorganic perspectives october 2007 chemistry department brookhaven national laboratory p. The metal oxide varistor or mov is a voltage dependent, nonlinear device that provides excellent transient voltage suppression. The varistors symmetrical, sharp breakdown characteristics enable it to provide excellent transient suppression performance. Variable resistors, such as the potentiometer and the rheostat, have ohmic characteristics. A varistorvoltage dependent resistor vdr is a component which has a voltage current characteristics that is. A metal oxide varistor, or mov, is an electronic component that protects equipment from voltage surges in a power line, such as from lightning strikes. Metal oxide varistor resistors mov online electronic surplus. Metaloxide varistor marking metal oxide varistor 20v510 varistor model harris varistors v 20v275 text.
The metal oxide varistor is designed to protect various types of electronic devices and semiconductor elements from switching and induced lightning surges. The downside is that if they stop a power surge, they can effectively burn out, but the user may have no idea this has happened. From this the behavior of the varistor can be interpreted for different current ranges. 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 sandwiched between two metal plates the electrodes. It is generally manufactured from a material such as zinc oxide, zno, although another. Varistor and the metal oxide varistor tutorial electronicstutorials.
Page 3 of 8 vi characteristic 105 104 103 102 101 10. It is called so as the component is made from a mixture of zinc oxide and other metal oxides like cobalt, manganese and. If you have questions about which harris metal oxide varistor you should order or you dont see the exact harris metal oxide varistor you need for your application, we can help. Nte1v010 thru nte1v300 nte2v010 thru ntev480 nte524v thru. Application guidelines overvoltage protection metaloxide. Metaloxide varistors movs radial lead varistors tmov. A varistor is an electronic component with an electrical resistance that varies with the applied. For some situations such has high gain amplifiers in audio applications, resistor noise is an unwanted phenomenon. They have become more and more important during the past four decades due to their highly nonlinear electrical characteristics and their large energy absorption capacity. The nte metal oxide varistors feature a barrier layer that gives the user fast. Select the right varistors for overvoltage circuit protection. Sep 22, 2015 the operation of metal oxide varistor and silicon carbide varistor are very similar. They have been intensively used in high power, high voltage applications. Please fill in the table and then change the color to white or invisible.
Allowable voltage varistor voltage withstanding surge current 8 20. Tsv dipped varistor ul vde and tsvc smd varistor youtube. The term is only used for nonohmic varying resistors. The name varistor is a portmanteau of varying resistor. 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.
The power so developed must be within the specifications shown on the. Electronics tutorial about the varistor and metal oxide varistor or mov which is used in power electronics circuits for protection against transients. Metal oxide nanoparticles marcos fernandezgarcia, jose a. Varistor or voltage dependent resistor vdr resistor guide. Jameco sells metal oxide varistor and more with a lifetime guarantee and same day shipping. These devices have a high transient current handling capability when high voltage is applied. The first generator was used for basic mov testing in order to produce the. Energy typical capacitance part number acrms dc dc volts 1 time vc ip 2 ms 10 1,000 s at 1 khz volts volts min. Leakage current region aug 17, 2011 how a common surge strip works explained by ge global research engineer bill morris. Each zno grain of the ceramic acts as if it has a semiconductor junction at the grain boundary. A simple equivalent circuit representing a metal oxide varistor as a capacitance in parallel with a voltage dependent resistor is shown in the.
An attractive property of the metal oxide varistor, fabricated from zinc oxide zno, is that the electrical characteristics are related to the bulk of the device. The surfaces of the intercrystalline fracture follow. Simple charge pump boosts input voltage by 50% this chargepump circuit, using just a few diodes and capacitors, ups the input voltage by a factor of 1. Metal oxide varistors consist of approximately 90% zinc oxide as a ceramic base material plus other filler materials for the formation of junctions. Basics horsepower hp a measure of the rate at which work is done 1 hp 746 watts 33,000 lbftmin 550 lbftsec power kw hp x 0. 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. But dependent on the application, many other properties may play a role. Varistors are voltage dependent, nonlinear devices which have an electrical behavior similar to backtoback zener diodes. Pdf comparative study of metal oxide varistors movs for. Many industry manufacturers, including current technology, integrate various sizes of radial or straptype movs into their products. During the sintering process the metal oxide powder transforms to a dense ceramic body with varistor properties. Metal oxide varistor b72220t2k101 thermofuse varistor advanced series etfv20ke2 kb kh pe 20070426 please read important notes at the end of this document. The series of a varistor varies depending on the voltage it can. Metal oxide variators mov or now generically referred to as siovs are commonly rated by their rms withstanding voltage or 385vac in this case, then above this by a joule rating 05 which seems low.
A surge in excess of the specified withstanding surge current may cause short circuits or package rupture with expulsion of material. Many industry manufacturers, including current technology, integrate. C iii metal oxide varistor series 6, second generation of metal oxide varistors. May 14, 2018 suntan is with very good support for multilayer metal oxide chip varistor. V xx e xxx harris varistor designation nominal disc diameter 07, 10, 14, 20mm, shown below.
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. Application guidelines overvoltage protection metal. A surge in excess of the specified withstanding surge current may cause short circuits or package rupture with expulsion. Pdf metal oxide varistors movs are the essence of surge protection devices. Varistor basics varistors primarily consist of arrays of zincoxide zno balls, in which the zno was altered with small amounts of other metal oxides such as bismuth, cobalt, or manganese.
Varistor symbol and applications metal oxide varistor. Metal oxide varistor described above, the mov is a nonlinear transient suppressor composed of zinc oxide zno silicon carbide varistor at one time this was the most common type before the mov came into the market. The gemov surge suppressor was developed first in 1973 by john d. For this we take mov metaloxide varistor which is the most common type of varistor. Littelfuse varistors basic properties, terminology and. The nte metal oxide varistors feature a barrier layer that gives the user fast response time. Metal oxide varistor mov technology is the most prevalent technology utilized in electrical transient protection products today.
Nte1v010 thru nte1v300 nte2v010 thru ntev480 nte524v thru nte524v48 metal oxide varistors mov description. The metal oxide varistor, mov, is the most widely used form of varistor. The basic dimensions in figure 1 to 5 are valid for types with either round or square. Simple and inexpensive, the mov absorbs the energy in a surge, preventing it from damaging other devices in a circuit.
Amperes volts amperes joules pf 11 14 16 20 100 36 1 0. The most common modern type of varistor is the metaloxide varistor mov. The series of a varistor varies depending on the voltage it can hold, the devices it is used to control, and the type of power used in its build. Suntan is with very good support for multilayer metal oxide chip varistor. Varistor working principle types metal oxide varistor. Figure 5 shows the simplified equivalent circuit of a metal oxide varistor. This type contains a ceramic mass of zinc oxide grains, in.
To specify a resistor, the most important parameter is resistance. Our online catalog includes information on hundreds of harris metal oxide varistors, such as specifications, photos and recommendations for accessories or other items. A metal oxide varistor mov is a nonlinear device which, than the normal line voltage while surge current flows, there is. Specifications are subject to change without notice.
Metal oxide nanoparticles brookhaven national laboratory. Mov14dxxxk series metal oxide varistor rohs directive 200295ec jan. Littelfuse varistors basic properties, terminology and theory. Metal oxide varistor mov, basics, working, specifications. Apr 18, 2020 the metal oxide varistor is not a perfect solution to power surges. They are a type of nonlinear device that feature similar characteristics to zener. 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. These varistors are used to protect circuits against excessive voltages. Users should verify actual device performance in their specific applications.
Failure study of metaloxide surge arresters sciencedirect. The main difference between a silicon carbide varistor and a metal oxide varistor is the amount of leakage current. Leakage current region pdf available october 20 with 323 reads how we measure reads. This type contains a ceramic mass of zinc oxide grains, in a matrix of other metal oxides, such as small amounts of. Energy typical capacitance part number acrms dc dc volts. The metal oxide varistor surge arresters movas are ceramic devices with highly nonlinear electrical characteristics similar to those of backtoback zener diodes. Normally, the mov has very high electrical resistance. Metal oxide varistor resistors mov online electronic. For example, a metal oxide varistor has a different build than a series built out of crystals. Varistors vary quite heavily between different models. Metal oxide varistor b72214q0511k101 energetiq series q14k510 kb kh pe 20070905 please read important notes at the end of this document. 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. If lightning strikes a nearby power line, the high voltage causes the mov to become a shunt, preventing the electrical surge from harming. A metal oxide varistor starts conducting current at rated voltage and it stops the conduction if the applied voltage is below the threshold value.
Page 4 of 11 characteristics 25 c ordering code type varistor voltage at 1 ma v clamping voltage at 100 a 820. Metal oxide varistors, more commonly known as movs are devices that provide excellent transient voltage suppression. They are cheap to manufacture, which means they are often used in inexpensive surge protectors. On the use of metal oxide varistors as a snubber circuit in solidstate breakers conference paper pdf available october 20 with 323 reads how we measure reads. Simple and inexpensive, the mov absorbs the energy in. Metal oxide varistor marking metal oxide varistor 20v510 varistor model harris varistors v 20v275 text. Vfd power quality issues protecting the vfd drops out below 70% voltage 30% sag. The most famous type of varistor is metal oxide varistor mov, which is also called as zno varistor. For this we take mov metal oxide varistor which is the most common type of varistor.
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