Zinc oxide varistor tvr14 seriesfor surge protection. Littelfuse varistors basic properties, terminology and theory. Only at those points where zinc oxide grains meet does sintering produce microvaristors, comparable to symmetrical zener diodes protection level approx. A test current of 1 ma dc is typically used to determine. After shaping, the varistors are sintered at high temperatures in speci. The most common modern type of varistor is the metal oxide varistor mov.
Znozno grain boundary, rich of bismuth, which is a highly resistive phase, is the main cause of. These properties then form the basis for defining the application parameters that are directly related to the nonlinear current. Typical capacitance reference ac rms v dc rms v w v 1. The resistance material in a metal oxide varistor mainly consists of zinc oxide grains that are pressed as a ceramic mass.
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. These varistors are composed of zinc oxide and some other metal oxides, which provide the desired characteristics for these varistors. Siov metal oxide varistors selection procedure date. Tvr10681 datasheet1443 pages etc1 zinc oxide varistor. Zinc oxide varistors ve 07091724 vf 0507101420 features radial lead varistors wide operating voltage range from 14 v to 625 v v rms for ve types or 22 v to v v 1ma for vf types available in tape and reel for use with automatic insertion. The varistor is composed primarily of zinc oxide with small additions of bismuth, cobalt, manganese and other metal oxides. 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. It is also a non linear device and provides very good transient voltage surge protection.
The hvr zno varistors have high voltage dependences and high current absorption. Bionanocomposites bncs were prepared using sago starch ss based polymer embedded with nanorods zinc oxide znon as nanofiller. 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. Features zinc oxide varistor are nonlinear resistors utilize a semiconductor electronic ceramic element mainly composed of zinc oxide and its resistors change as a function of the applied voltage. Vdrs series vdr metal oxide varistors standard vishay. Transmission electron microscope tem and scanning electron microscope sem were used to analyze the morphology and dispersion of znon in bncs. The arrester provides overvoltage system protection in an insulated, fully shielded, submersible, deadfront device. They are bilateral and symmetrical vi characteristics curve and unparalleled largepeak current capability are used for absorption of transient voltage,suppression of pulse noise and circuit voltage stabilization. Zinc oxide varistors introduction zinc oxide varistors. This paper deals with the application of zno varistors an area which has not been treated in a systematic way in the literature. Browse a selection of varistors, including the metal oxide varistor, today.
These parts are then electroded with either thick film. Zinc oxide varistor is a nonlinear resistance device, whose voltage and current relationship vary according to the. Varistor symbol and applications metal oxide varistor. Tvr10241 datasheet, tvr10241 pdf, tvr10241 pinout, equivalent, replacement high surge zinc oxide varistor tks, schematic, circuit, manual. The fully three dimensional current distribution is computed by means of a nonlinear. Tvr14331, tvr14361, tvr14391, tvr14431, tvr14471, tvr14511,tvr14561 after you confirm the model, we will send you the samples and datasheet of this model free samples part number code full model example. Metal oxide varistors definition of varistor terms rated rms voltage, rated dc voltage the maximum designated values of power system voltage that may be applied continuously between the terminals of a device varistor voltage test characteristic that is used to classify varistors by type. Zinc oxide is the primary crosslinker and adequate curing can be realized with as little as 1. The electrical transport in zinc oxide zno varistors is analyzed using microstructural material modeling. Zinc oxide varistors are strongly nonlinear resistors that have been used to regulate transient voltage surges of unwanted magnitude for high voltage and powerrelated applications, such as surge arresters in power transmission and distribution for the protection of electronic devices. Vdr metal oxide varistors standard additional resources ordering information the varistors are available in a number of packaging options. A study described how microemulsionmediated zinc oxide nanoparticles were synthesized for varistor studies. In other words, within a given current range, the currentvolt.
The paper starts with a brief description of the fundamental properties comprising the electrical behavior as well as the physics, chemistry, and microstructure of the varistor. Pdf modeling of electrical transport in zinc oxide varistors. Fnr07k471 datasheet, fnr07k471 pdf, fnr07k471 pinout, equivalent, replacement zinc oxide varistor fenghua advanced technology, schematic, circuit, manual. Directwrite fabrication of zinc oxide varistors valeria tohver, sherry l. They exhibit a highly nonlinear currentvoltage relation with a 5%. Lewis department of materials science and engineering, university of illinois, urbana, illinois 61801. Zinc oxide zno varistors is a solid state electronic ceramic component whose function to protect electronic devices against over voltage surges due to. Ksy the suffixes ksw is the high surge protection tvrd series.
Stability of zinc oxide varistors a thesis submitted to the university of manchester for the degree of doctor of philosophy in the faculty of engineering and physical sciences 2014 poonsuk poosimma school of materials. Metal oxide varistor mov parking stand surge arrester general eatons cooper power series parking stand arrester combines metal zinc oxide varistor technology with a premolded rubber insulated standoff bushing. Zinc oxide varistors consist mainly of zinc oxide about 90 % by weight and small amounts of other metal oxides additives such as bismuth, cobalt, antimony. Movs present a nonlinear resistance characteristic that is approximated by fundamental frequency nonlinear impedance during short circuit calculations. Ingredients zinc oxide varistors consist mainly of zinc oxide about 90 % by weight and small amounts of other metal oxides additives such as bismuth, cobalt, antimony and manganese oxide. The power so developed must be within the specifications shown on the. Fnr07k471 datasheet pdf pinout zinc oxide varistor. The zno varistor is a mutiphase polycrystalline ceramic made by. Zinc oxide varistors are electronic ceramic materials whose electrical behavior is dominated by grainboundary interface states. These nanoparticles were ultrafine with a size ranging from 5 to 40 nm esd.
Zinc oxide varistor tvr07 seriesfor surge protection. In this region, the ohmic resistance of the zinc oxide causes a higher voltage drop across the varistor that carries the higher surge current. Thus, the current distribution is shifted to the varistor. This product has tvr series zinc oxide varistor functions. However, concentrations below 4 phr fail to provide the full age resistance potential of this polymer. Cnr dvph series metal oxide varistor are nonlinear resistors, consisting main of zinc oxide and several kinds of metal oxide additive. Recycling zinc oxide varistor blocks for electroa wiley online library. This part name is tvr14621 manufacturers of product is tks. Recycling zinc oxide varistor blocks for electroactive silicone composites. Metal oxide varistor mov parking stand surge arrester.
Zinc oxide and magnesium oxide are the principal crosslinking agents for sm neoprene, and, as such, must be examined in terms of both concentration and interaction with silica. Protection function application definition of the varistor effect the varistor effect is defined as being the property of any material whose electrical resistance changes nonlinearly with the voltage applied to its terminals. 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. Are nonlinear resistors utilize a semiconductor electronic ceramic element mainly composed of zinc oxide and its resistors change as.
Varistorlike effect in zinc oxide bionanocomposite. Vdrs series vdr metal oxide varistors standard, available from vishay intertechnology, a global manufacturer of electronic components. Both bi 2o 3rich and zn 7sb 2o 12 spinel phases are also usually present at the grain boundaries of the zno, but the presence of a bi 3zn 2sb3o14 phase is possible as well. Zinc oxide varistor suntan tsv zinc oxide varistor 14d specification part no maximum allowable voltage maximum energy 10s j maximum peak current 820s rated power varistor voltage clamping voltage max. Metal oxide varistors consist of approximately 90% zinc oxide as a ceramic base material plus other filler materials for the.
The percentage of znon was varied from 2 weight percent wt % to 10 wt % of total solid. The iv characteristics measured at rt remained unchanged in the presence of h 2, but the breakdown voltage clearly shifted to a lower electric field in the temperature range. Tvr14621 tvr series zinc oxide varistor, pdf, pinout, equivalent, replacement, schematic, manual, data, circuit, parts, datasheet. Application of zinc oxide varistors gupta 1990 journal of the. Metal oxide varistor is a voltage dependent resistor. Tvr10241 datasheet pdf pinout high surge zinc oxide. The results showed that reducing the average size of the. Tvr10681 datasheet pdf 14 page list of unclassifed manufacturers. Metal oxide znobased varistor ceramics 331 conductors. The boundary between each grain and a neighbor forms a diode junction, which allows. The electrical behavior of the metal oxide varistor, as indicated by figure 3, results from the number of microvaristors connected in series or in parallel. Effect of sintering temperature on zinc oxide varistor. Zinc oxide varistors ve 07091724 vf 0507101420 features radial lead varistors wide operating voltage range from 14 v to 625 v v rms for ve types or 22 v to v v 1ma for vf types available in tape and reel for use with automatic insertion equipment see pages 31 to 33 for details. The energy of the incoming surge is partially conducted and partially absorbed, protecting the circuit.
The most recent application of zinc oxide nanoparticles is seen in varistors. Part no maximum allowable voltage maximum energy 10s j maximum peak current 820s rated power var istor voltage clamping voltage. Pdf zinc oxide varistors are electronic ceramic materials whose electrical behavior is dominated by grainboundary interface states. They are constructed of a sintered matrix of zinc oxide zno grains. To find the varistor that meets your needs, start with littelfuse. They are manufactured mainly as discs with varying sizes, as the required electric values are most easily obtained with these geometric dimensions. Sailing electronics zhejiang huangyan sailing electronics co. Var series zinc oxide varistor va r d k packing type. An experimental study of the failure mode of zno varistors. Mechanical properties and microstructure of zinc oxide.
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