wikitionary VoltageVoltage abbreviated V is the term for the difference in electric potential energy. It may also refer to Electrical Engineering Voltage divider , a circuit that produces an output voltage that is a fraction of its input Voltage reference , an electronic device that produces a constant voltageVoltage regulator , an electronic device designed to maintain a constant voltageVoltage source , a circuit theory term, the dual of a current source. Voltage spike , an electrical engineering term for sudden changes in voltageVoltage controlled filter VCF , a type of electronic filter Voltage controlled amplifier VCA , a type of electronic amplifier Places Voltage , an unincorporated community in Harney County, Oregon, United States See also Volt disambiguation Ampere disambiguation disambiguation NOTOC ... more details
Refimprove date December 2009 In electrical engineering , particularly power engineering , voltage regulation is the ability of a system to provide near constant voltage over a wide range of Electrical load load conditions. Electrical power systems In electrical power systems it is a dimensionless quantity defined at the receiving end of a transmission line as math Voltage Regulation VR frac V nl V Rated V Rated times 100 math ref cite book last Chapman first Stephen J. title Electric Machinery Fundamentals year 2005 publisher McGraw Hill isbn 978 0 07 246523 5 pages 100, 263. ref where V sub nl sub is voltage at no load and V sub Rated sub is voltage at full load. A smaller value of VR is usually beneficial. The Voltage Regulation formula could be visualized with the following Consider power being delivered to a load such that the voltage at the load is the load s rated voltage V sub Rated sub , if then the load disappears, the voltage at the point of the load will rise to V sub nl sub . Electronic power supply parameters The quality of a system s voltage regulation is described by three main parameters class wikitable border 1 Parameter S sub T sub Measure of the ability to maintain a constant output voltage, regardless of variations in temperature of electrical components within the system, especially semiconductor based devices. Sometimes, the term voltage regulation is used to describe processes by which the quantity VR is reduced, especially concerning special circuits and devices for this purpose, voltage regulators . Voltage regulators are an important part of power ... point the point at which the equipment tries to maintain constant voltage. Customers further than this point observe an expected effect higher voltage at light load, and lower voltage at high load. Customers closer than this point experience the opposite effect higher voltage at high load, and lower voltage at light load. References Reflist See also Voltage regulator DEFAULTSORT Voltage Regulation ... more details
File Voltage portal.jpg thumb Cut away view of a voltage portal A Voltage portal extends a voltage source to the outside of an Enclosure electrical electrical enclosure in an encapsulated non conductive housing designed for a Non contact voltage detector NCVD to sense voltage if placed into the voltage portal. Overview A voltage portal avoids voltage exposure for workers by extending the voltage source points to the outside of electrical enclosures. Each voltage point resides in an encapsulated non conductive housing designed to insure that a NCVD senses voltage if placed into the voltage portal Fig. 1 . Because a voltage portal contains Live wire electricity live voltage and mounts on the outside of an electrical enclosure, it must be robust to insure long term safety. The Underwriters Laboratories UL enclosure type rating of the voltage portal must also match the enclosure rating. Maintenance work Many maintenance workers carry NCVD pens or AC voltage detector s in their tool belts. This portable device allows workers to quickly check electrical conductors for live voltage without actually touching the bare wire. The NCVD can sense voltage when positioned close to the live conductor without making a hard wired electrical connection. A voltage portal is used to assist workers in creating an electrically safe work condition as part of a lockout tagout procedure before beginning work on electrical or mechanical equipment. References Reflist External links http graceport.com assets files Application 20Notes Application VoltagePortals 20Improve 20NCVD.pdf http www.mt online.com component content article 295 june2011 1794 electrical safety sense better voltage detection.html Categories Category Articles created via the Article Wizard Category Electrical components Category Electrical safety ... more details
Orphan date February 2009 In telecommunication , a disturbance voltage is an unwanted voltage induced in a system by natural or man made sources. In telecommunications systems, the disturbance voltage creates current electricity current s that limit or interfere with the interchange of information . An example of a disturbance voltage is a voltage that produces a false signals in a telephone , b noise in a radio receiver, or c distortion in a received Signalling telecommunication signal . References FS1037C Category Electrical parameters Category Telecommunications terms Category Noise telecomm term stub ... more details
In electronics , the dropout voltage of a voltage regulator is the smallest possible difference between the input voltage and output voltage to remain inside the regulator s intended operating range. For example, a regulator with 5 volt output and 2 volt dropout voltage rating will only output 5 volts if the input voltage is above 7 volts 7 volt input 5 volt output 2 volt dropout . If the input falls below 7 volts the output will fail to regulate to 5 volts. Dropout voltage can be as high as 2 volts for a general purpose integrated circuit regulator such as the 78xx series , but a low dropout regulator may have a dropout of less than 100 mV at full load. Dropout voltage will vary depending on the load on the regulator, usually increasing under higher load, due to the internal resistance of the regulator s pass transistor and circuitry. Dropout voltage also varies with respect to temperature. Dropout voltage is usually specified over a range of loads and temperatures. electronics stub Category Electrical parameters ... more details
Unreferenced date December 2009 A voltage ladder is a simple electronic circuit consisting of several resistor s connected in Series circuit series with a voltage placed across the entire resistor network. Voltage ladders are useful for providing a set of successive voltage references, for instance for a Flash ADC Flash analog to digital converter . How it works A voltage drop occurs across each resistor in the network causing each successive rung of the ladder each node of the circuit to have a higher voltage then the one before it. Ohm s law can be used to easily calculate the voltage at each node. Since the ladder is a series circuit, the Electric current current is the same throughout, and is given by the total voltage divided by the total resistance V R sub eq sub , which is just the sum of each series resistor in the ladder. The voltage drop across any one resistor is now given simply by I R sub n sub , where I is the current calculated above, and R sub n sub is the resistance of the resistor in question. The voltage referenced to Ground electricity ground at any node is simply the sum of the voltages dropped by each resistor between that node and ground. Alternatively, you can use Voltage divider rule voltage division to determine node voltages without having to calculate the current directly. By this method, the voltage drop across any resistor is V R sub n sub R sub eq sub where V is the total voltage, R sub eq sub is the total equivalent resistance, and R sub n sub is the resistance of the resistor in question. The voltage of a node referenced to ground is still the sum of the drops across all the resistors, but it s now easier to consider all these resistors as a single equivalent resistance R sub T sub , which is simply the sum of all the resistances between the node and ground, so the node voltage is given by V R sub T sub R sub eq sub . DEFAULTSORT Voltage Ladder Category Electronic circuits ... more details
Refimprove date November 2010 In electric circuit theory , an ideal voltage source is a circuit element where the voltage across it is independent of the current through it. A voltage source is the dual electronics dual of a current source . In analysis, a voltage source supplies a constant DC or AC ... of an ideal voltage source and additional combinations of Electrical impedance impedance elements. Image Ohms law voltage source.svg 150px thumb A schematic diagram of an ideal voltage source, V , driving a resistor, R , and creating a current I Ideal voltage sources An ideal voltage source is a mathematical abstraction that simplifies the analysis of electric circuits. If the voltage across an ideal voltage source can be specified independently of any other variable in a circuit, it is called an independent voltage source. Conversely, if the voltage across an ideal voltage source is determined by some other voltage or current in a circuit, it is called a dependent or controlled voltage source . A mathematical model of an amplifier will include dependent voltage sources whose magnitude ... network of interconnected sources and transmission lines can be usefully replaced by an ideal AC voltage ... 2em 0 Image Voltage Source.svg style padding 1em 2em 0 Image Current Source.svg align center Voltage Source Current source Current Source align center style padding 1em 2em 0 Image Voltage Source Controlled .svg style padding 1em 2em 0 Image Current Source Controlled .svg align center Controlled Voltage ... float end caption Symbols used for voltage sources The internal resistance of an ideal voltage source is zero it is able to supply or absorb any amount of current. The current through an ideal voltage ... approaches infinity as the load resistance approaches zero a short circuit . Thus, an ideal voltage source can supply unlimited power. No real voltage source is ideal all have a non zero effective ... voltage source is effectively modeled in linear circuit analysis by combining a non zero resistance ... more details
Refimprove article date April 2007 Image Voltage spike.png frame Voltage spike In electrical engineering , spikes are fast, short duration electrical transient electricity transient s in voltagevoltage spikes , current current spikes , or transferred energy energy spikes in an electrical circuit. Fast, short duration electrical transients overvoltage s in the electric potential of a electrical network circuit are typically caused by Lightning strikes Power outages Tripped circuit breaker s Short ... from 1 kHz into the gigahertz range through the atmosphere. The effect of a voltage ... voltage spikes may be created by current sources. Voltage would increase as necessary so that a constant ... , excessive current can flow if this voltage spike exceeds a material s electrical breakdown breakdown voltage, or if it causes avalanche breakdown . In semiconductor p n junction junctions , excessive electric current may destroy or severely weaken that device. An avalanche diode , transient voltage ... minimizing voltage. ref Transient Protection, LearnEMC Online Tutorial. http www.learnemc.com tutorials Transient Protection t protect.html ref While generally referred to as a voltage spike, the phenomenon ... s a transient response defined by a mathematical product of voltage , Electric current current , and time. Voltage spikes may be created by a rapid buildup or decay of a magnetic field, which may Electromagnetic induction induce energy into the associated circuit. However voltage spikes can also have more mundane causes such as a fault in a transformer or higher voltage primary circuit power wires falling onto lower voltage secondary circuit power wires as a result of accident or storm damage. Voltage .... Each type of spike requires selective use of protective equipment. For example a common mode voltage ... voltage increase that lasts more than a few seconds is usually called a voltage surge rather than ... also Uninterruptible power supply Power quality Surge protector References Reflist DEFAULTSORT Voltage ... more details
IEC voltage ranges Low voltage , when used as an electrical engineering term concerning an Electrical grid electricity supply grid or Industry industrial use, broadly identifies safety considerations of the system based on the voltage used. The meaning of the term low voltage is somewhat different when used with regard to a more typical end user s distribution system, which see below. Electricity supply system With regard to an Electric power distribution electricity supply system , low voltage most commonly refers to Mains electricity mains voltage . Low voltage in this context is characterized by carrying a substantial risk of electric shock , but only a minor risk of electric arc s through air. Also in this context, Low voltage is distinguished from Extra low voltage Extra low voltage supply system which carries a much reduced risk of electric shock High voltage High voltage supply system where electrical arcing is a substantial additional risk. Other definitions Some other commonly used definitions include The International Electrotechnical Commission IEC defines low voltage as any voltage in the range 50 1000 V Alternating current AC or 120 1500 V Direct current DC . Article 490.2 of the United States 2005 National Electrical Code only defines high voltage as more than 600 volts. Nevertheless the NFPA 79 article 6.4.1.1 defines PELV as nominal voltage of 30 Vrms or 60 Vdc ripple free for dry locations and 6 Vrms or 15 Vdc in all other cases. UL 508A article 43 Table 43.1 is more stringent and defines 0 20V peak 5A or 20.1 42.4V peak 100VA as Low Voltage Limited Energy circuits. Within the context of the distribution system the United States 2005 National Electrical Code NEC defines low distribution system voltage as 0 49 volts . . Low Distribution system voltage is covered by 250.20 A of this code. British Standard BS 7671 2008 defines low voltage as 50 1000 V AC ... and Earth. See also Low Voltage Directive References Reflist DEFAULTSORT Low Voltage Category ... more details
In telecommunication , a longitudinal voltage is a voltage induced or appearing along the length of a transmission medium . Note 1 Longitudinal voltage may be effectively eliminated by using differential amplifiers or receivers that respond only to voltage differences, e.g., those between the wires that constitute a pair. Note 2 Induced longitudinal voltages at low Electric power transmission power line frequencies can be greatly reduced by twisting parallel wires to create what are referred to as twisted wire pairs. Synonym common mode voltage. FS1037C Category Electrical parameters Category Telecommunications terms ... more details
Psophometric voltage is a Electronic circuit circuit noise voltage measured with a psophometer that includes a CCIF 1951 weighting filter weighting network . Psophometric voltage should not be confused with psophometric emf, i.e. , the emf in a generator or line electrical engineering line with 600 internal resistance. For practical purposes, the psophometric emf is twice the corresponding psophometric voltage. Psophometric voltage readings, V , in millivolts, are commonly converted to dBm psoph by dBm psoph 20 log sub 10 sub V 57.78. References FS1037C Category Electrical parameters Category Noise Category Telecommunications terms electronics stub telecomm term stub ... more details
Refimprove date September 2010 File 7812 voltage regulator.jpg thumb right A popular three pin 12 V DC voltage regulator IC. A voltage regulator is an electricity electrical regulator automatic control regulator designed to automatically maintain a constant voltage level. A voltage regulator may be a simple .... Electronic voltage regulators are found in devices such as computer power supply power supplies where ... s and central power station generator plants, voltage regulators control the output of the plant. In an electric power distribution system, voltage regulators may be installed at a substation or along distribution lines so that all customers receive steady voltage independent of how much power is drawn from the line. Measures of regulator quality The output voltage can only be held roughly constant the regulation is specified by two measurements load regulation is the change in output voltage for a given ... 5mA and 1.4A, at some specified temperature and input voltage . line regulation or input regulation is the degree to which output voltage changes with input supply voltage changes as a ratio of output to input change for example typically 13mV V , or the output voltage change over the entire specified input voltage range for example plus or minus 2 for input voltages between 90V and 260V, 50 60Hz . Other important parameters are Temperature coefficient of the output voltage is the change in output voltage with temperature perhaps averaged over a given temperature range , while... Initial accuracy of a voltage regulator or simply the voltage accuracy reflects the error in output voltage for a fixed ... voltage is the minimum difference between input voltage and output voltage for which the regulator ... to work well even with an input supply only a Volt or so above the output voltage. The input output differential at which the voltage regulator will no longer maintain regulation is the dropout voltage. Further reduction in input voltage will result in reduced output voltage. This value is dependent ... more details
Refimprove date November 2010 A voltage reference is an electronic device that produces a fixed constant voltage irrespective of the loading on the device, power supply variations, temperature changes, and the passage of time. Voltage references are used in power supply voltage regulator s, analog to digital .... Voltage references vary widely in performance a regulator for a computer power supply may only hold its value to within a few per cent of the nominal value, whereas laboratory voltage standards have precisions and stability measured in parts per million . In metrology The earliest voltage references ... state voltage standards used in metrology can be constructed with a drift of about 1 part per million ... p. 289 ref The value of the volt is now defined by the Josephson Effect to get a voltage to an accuracy ... in 1973. Formerly, mercury battery mercury batteries were much used as convenient voltage references ... stable discharge voltage over their useful life. Solid state devices Any semiconductor diode has an exponential voltage current characteristic that gives an effective knee voltage sometimes used as a voltage reference. This voltage ranges from 0.3 V for germanium diodes up to about 3 volts for certain ... frequently used to provide a reference voltage of moderate stability and accuracy, useful for many electronic devices. An avalanche diode displays a similar stable voltage over a range of current. The most ... having an overall voltage drop of 6.2 V at 7.5 mA, but are also sometimes included in integrated circuits. The most common voltage reference circuit used in integrated circuits is the bandgap voltage ... of the voltage difference between two bipolar junctions biased at different current densities to the voltage developed across a diode. The diode voltage has a negative temperature coefficient i.e. it decreases with increasing temperature , and the junction voltage difference has a positive temperature ..., the resultant constant value is a voltage equal to the bandgap voltage of the semiconductor. In silicon ... more details
Voltage drop is the reduction in voltage in the passive elements not containing sources of an electrical electrical network circuit . Voltage drops across Electrical conductor conductor s, Electrical contact ... the supplied voltage while voltage drops across Electrical load load s and other electrical ... wiring , national and local electrical code s may set guidelines for maximum voltage drop allowed ... equipment the maximum permitted voltage drop varies from one country to another http www.electrical installation.schneider electric.com voltage drop.htm . Voltage drop may be neglected when ... that 2 of the supplied voltage is lost in the wire itself. Excessive voltage drop will result ... system. Voltage drop can also cause damage to electrical motors. In electronic design and power transmission, various techniques are used to compensate for the effect of voltage drop on long circuits or where voltage levels must be accurately maintained. The simplest way to reduce voltage drop is to increase .... The more sophisticated techniques use active elements to compensate the undesired voltage drop. Voltage drop in direct current circuits A current flowing through the non zero Electrical resistance resistance of a practical Electrical conductor conductor necessarily produces a voltage across ... area, type of material, and temperature. Image Line voltage diagram.jpg right thumb 500px center The local voltages along a long line decrease gradually from the source to the load center If the voltage ..., the measured voltage will decrease gradually toward the load. As the current passes through a longer and longer conductor, more and more of the voltage is lost unavailable to the load , due to the voltage drop developed across the resistance of the conductor. In this diagram the voltage drop along ... from the source to the load. If the load current increases, the voltage drop in the supply conductor also increases. Voltage drop exists in both supply and return wires of a circuit. A principle ... more details
Multiple issues unreferenced December 2009 orphan February 2009 context October 2009 In a power system, voltage at various Electrical bus buses tends to increase or decrease during its daily operation. To ensure constant voltage to consumers, various techniques are utilized. When the voltage is below the required level, reactive power produced by inductance needs to be offset by capacitance. Synchronous condenser s&mdash can be used to generate reactive power, when they are operated as a motor. Shunt Capacitance &mdash Capacitor banks can be connected in Series and parallel circuits Parallel circuits parallel to the transmission lines. Series Capacitance &mdash Capacitors connected in series, especially for long lines can be used to raise the voltage. Tap Changing Transformers &mdash Transformer tappings can be automatically changed, to alter the voltage accordingly. When the voltage is above the required level, reactive power produced by capacitance needs to be offset by inductance. Shunt Reactors &mdash Inductor banks can be connected in Series and parallel circuits Parallel circuits parallel to the transmission lines also known as reactors. Static VAr Compensator s&mdash Tap Changing Transformers &mdash Transformer tappings can be automatically changed, to alter the voltage accordingly. DEFAULTSORT Voltage Compensation Category Electrical systems Energy stub ... more details
Multiple issues orphan February 2009 context October 2009 Overdrive voltage , usually abbreviated as V sub OV sub , is typically referred to in the context of MOSFET transistors . The overdrive voltage is defined as the voltage between transistor gate and source V sub GS sub in excess of the threshold voltage V sub t sub where V sub t sub is defined as the minimum voltage required between gate and source to turn the transistor on allow it to conduct electricity . Due to this definition, overdrive voltage is also known as excess gate voltage or effective voltage. ref Sedra and Smith, Microelectronic Circuits, Fifth Edition, 2004 Chapter 4, ISBN 978 0 19 533883 6 ref Overdrive voltage can be found using the simple equation V sub OV sub V sub GS sub V sub t sub . Technology V sub OV sub is important as it directly affects the output current I sub D sub of the transistor, an important property of amplifier circuits. By increasing V sub OV sub , I sub D sub can be increased until Saturation current saturation is reached. Overdrive voltage is also important because of its relationship to V sub DS sub , the drain voltage relative to the source, which can be used to determine the region of operation of the MOSFET. The table below shows how to use overdrive voltage to understand what region of operation the MOSFET is in class wikitable Conditions Region of Operation Description V sub DS sub V sub OV sub V sub GS sub V sub t sub Saturation CCR The MOSFET is delivering a high amount of current ... Triode Linear The MOSFET is delivering current in a linear relationship to the voltage V sub DS sub ... sub 0 we attract MORE holes, and this is called accumulation. A positive gate voltage V sub GS sub 0 ... of holes. At a critical voltage called the THRESHOLD VOLTAGE V sub t sub or V sub th sub the channel ... silicon, and this is called the inversion region. As we increase this voltage, V sub GS sub , beyond ... the OVERDRIVE VOLTAGE Called often V sub ov sub , V sub od sub , or V sub on sub is defined as V sub ... more details
In electronics , the cutoff voltage is the voltage at which a battery is considered fully discharged, and it is good practice to stop discharge at this point. Some electronic devices, such as cell phones, will automatically shut down when the cutoff voltage has been reached. Batteries In batteries,the cutoff final voltage is the prescribed lower limit voltage at which Battery electricity battery discharge is considered complete. The cutoff voltage is usually chosen so that the maximum useful capacity of the battery is achieved. The cutoff voltage is different from one battery to the other and it s highly dependent on the type of battery and the kind of service in which the battery is used. When testing the capacity of a NiMH or Nickel cadmium battery NiCd battery a cutoff voltage of 1.0 V is normally used. 0.9V is normally used as the cutoff voltage of an alkaline cell . Devices that have too high cutoff voltages may stop operating while the battery still has significant capacity remaining. ref cite journal last Warner first R.M., Jr. date June 1963 title Epitaxial FET cutoff voltage journal Proceedings of the IEEE volume 51 issue 6 pages 939 940 issn 939 940 ref Premature voltage cut off Some wikt portable portable equipment does not fully use the low end voltage spectrum of a Battery electricity battery . The equipment cuts off before the designated end of discharge voltage is reached, leaving some battery power unused. A high cutoff voltage problem is more widespread than is commonly assumed. For example, a certain brand of mobile phone that is powered with a single cell Lithium ion battery cuts off at 3.3V. The Li ion can be discharged to 3V and lower. With a discharge ... of Low Voltage Cut Off Relay Circuits http cat.inist.fr ?aModele afficheN&cpsidt 17248454 Effect of discharge cut off voltage on cycle life of MgNi based electrode for rechargeable Ni MH batteries http www.electronics lab.com projects motor light 042 index.html High And Low Voltage Cut Off With Time ... more details
distinguish clamper electronics File voltage clamp.jpg thumb 277px right The voltage clamp operates by negative feedback. The membrane potential amplifier measures membrane voltage and sends output to the feedback amplifier this subtracts the membrane voltage from the command voltage, which it receives ... electrode. Portal Neuroscience The voltage clamp is used by electrophysiology electrophysiologists ..., such as neuron s, while holding the membrane voltage at a set level. Cell membranes of excitable cells contain many different kinds of ion channels, some of which are Voltage gated ion channel voltage gated . The voltage clamp allows the membrane voltage to be manipulated independently of the ionic currents, allowing the Current voltage characteristic current voltage relationships of membrane ... Science , 4th ed. pp.152 153. McGraw Hill, New York ref The concept of the voltage clamp is due to Kenneth ... to voltage clamp Trends in Neurosciences 25 553 558 ref After experiments with the voltage clamp ... they shared the 1963 Nobel Prize in Physiology or Medicine . ref name Huxley Technique The voltage clamp is a current generator with two electrodes. Transmembrane voltage is recorded through a voltage .... The experimenter sets a holding voltage , or command potential , and the voltage clamp uses negative feedback to maintain the cell at this voltage. The electrodes are connected to an amplifier ..., and sends an output to the current electrode. Whenever the cell deviates from the holding voltage ... potential and the actual voltage of the cell. The feedback circuit passes current into the cell ... the membrane. Cole developed the voltage clamp technique before the era of microelectrode s, so ... . The squid giant axon was the first preparation that could be used to voltage clamp a transmembrane ... potential. Variations of the voltage clamp technique A more detailed discussion of the below ... downloaded in PDF form from Axon Instruments . Two electrode voltage clamp using microelectrodes This works ... more details
File Square1.jpg thumb High voltage dielectric breakdown within a block of plexiglas The breakdown voltage of an Insulator electrical insulator is the minimum voltage that causes a portion of an insulator to become electrically Conductor material conductive . The breakdown voltage of a diode is the minimum reverse voltage to make the diode conduct in reverse. Some devices such as TRIAC s also have a forward breakdown voltage . ref Emelyanov, A.A. and Emelyanova, E.A., Abstracts of Papers, Proc. XXII ISDEIV, Matsue, 2006, vol. 1, p. 37. ref Solids Breakdown voltage is a characteristic of an Electrical insulation insulator that defines the maximum Breakdown potential voltage difference that can ... of lamps, breakdown voltage is also sometimes called the striking voltage . ref J. M. Meek and J. D. Craggs, Electrical Breakdown of Gases, John Wiley & Sons, Chichester, 1978. ref The breakdown voltage ... probability whether the material will fail at a given voltage. When a value is given it is usually the mean breakdown voltage of a large sample. Another term is also withstand voltage where the probability of failure at a given voltage is so low it is considered, when designing insulation, that the material will not fail at this voltage. ref Relationship between Electrode Surface Roughness and Impulse Breakdown Voltage in Vacuum Gap of Cu and Cu Cr Electrodes , Shinji Sato and Kenichi Koyama ... City, Hyogo 661 8661, Japan ref Two different breakdown voltage measurements of a material are the AC and impulse breakdown voltages. The AC voltage is the utility frequency line frequency of the mains . The impulse breakdown voltage is simulating lightning strikes, and usually uses a 1.2 microsecond ... insulator, requiring the application of a significant voltage before breaking down e.g. lightning ... vysokikh napryazhenii High Voltage Engineering , Leningrad Energiya, 1967. ref The breakdown voltage ... at 50 Hz of a Vacuum ref ref R. V. Latham, High Voltage Vacuum Insulation Basic concepts and technological ... more details
Unreferenced date August 2009 A voltage converter changes the voltage of an electrical power source. It may be combined with other components to create a power supply . AC and DC AC voltage conversion uses a transformer . Conversion from one DC voltage to another requires electronic circuit ry electromechanical equipment was required before the development of semiconductor device semiconductor electronics ... voltage converters Mains converters A common use of the term voltage converter is for a device that allows appliances made for the mains voltage of one geographical region to operate in an area with different voltage. Such a device may be called a voltage converter , power converter , travel ... are inherently reversible, so the same transformer can be used to step the voltage up, or step it down by the same ratio. Lighter and smaller devices can be made using electronic circuitry reducing the voltage ... designed to operate at 60 Hz may overheat at 50 Hz even if the voltage supplied is correct. Most mains powered electrical equipment can be used either on any voltage from 100 to 120V, or on any voltage from 210 to 240 V so that voltage converters need only be specified to convert any voltage in one range to a voltage in the other, rather than separate converters being required ... converters Another requirement is to provide low voltage electricity to a device from mains electricity ... converters, and are often designed to work from AC mains at any voltage between 100 and 240V. Additionally, because they are typically rectified to operate at a DC voltage, they are minimally affected ... supplies . Mobile converters Voltage converters can be used in vehicles with 12 V DC outlets. A simple voltage dropper can be used to reduce the voltage for low power devices if more than 12V ... DC to AC rather than the voltage change. The output frequency and waveform of an inverter may not accurately ... Extra low voltage Low voltage High voltage References reflist DEFAULTSORT Voltage Converter Category ... more details
image Voltage Multiplier diagram.PNG thumb right 280px Villard cascade voltage multiplier. A voltage multiplier is an electrical circuit that converts AC electrical power from a lower voltage to a higher DC voltage, typically using a network of capacitor s and diode s. Voltage multipliers can be used ... physics experiments and lightning safety testing. The most common type of voltage multiplier is the half ... Greinacher . Operation Assuming that the peak voltage of the AC source is U sub s sub , and that the C ... in voltage, then the simplified working of the cascade is as follows Image Voltage amplifier explain.png ... C sub 4 sub to 2U sub s sub . The output voltage the sum of voltages under C sub 2 sub and C sub ... voltage. Each additional stage of two diodes and two capacitors increases the output voltage by twice the peak AC supply voltage. Voltage doubler and tripler seealso Voltage doubler A voltage doubler uses two stages to approximately double the DC voltage that would have been obtained from a single stage rectifier. An example of a voltage doubler is found in the input stage of switch mode power .... In the 120 volt position the input is typically configured as a full wave voltage doubler by opening ... system. This allows 120 or 240 volt operation with the addition of a simple SPDT switch. A voltage tripler is a three stage voltage multiplier. A tripler is a popular type of voltage multiplier. The output voltage of a tripler is in practice below three times the peak input voltage due to their high ... supplies power to the next, it partially discharges, losing voltage doing so. Triplers were commonly used in color television receivers to provide the high voltage for the cathode ray tube picture tube .... cn date November 2011 Triplers are still used in high voltage supplies such as copier s, laser printer s, insect electrocutors. Breakdown voltage While the multiplier can be used to produce ... voltage range. Each component only needs to be concerned with the relative voltage differences ... more details
loads provide only short term benefits. A phenomenon known as load diversity plays a role in voltage ... nature of these loads, the aggregate peak can remain relatively constant. However, if the voltage ... upon initiating voltage reduction, over time water heaters will need to be on longer to achieve ... resistive loads the benefits of voltage reduction can be short lived, and may occasionally end up increasing the aggregate load demand. The keen eye may also realize that by increasing the voltage ... reading lamp with higher voltage than it would at a lower voltage. External links http www.ieso.ca imoweb siteShared voltage reduction.asp?sid ic DEFAULTSORT Voltage Reduction Category Electric ... more details
Sky voltage refers to an electrostatic voltage gradient that is present in the free air of the atmosphere, and which can have a different voltage potential relative to the surface of the planet. The gradient varies with atmospheric humidity, dropping lower on days with high humidity, and higher in very dry air. The voltage potential averages about 120 volts per meter. ref Popular Science magazine, The Amazing Motor that Draws Power from the Air , April 1971, p80 81 p154. Direct link to cited article, scanned by Google Books http books.google.com books?id kwAAAAAAMBAJ&pg PA80&lpg PA80 ref Tall insulated metallic objects can absorb these voltage gradients out of the atmosphere, and conduct the voltage to a terrestrial collection and measurement station. Small lightweight electrostatic motors and toys can be driven from this collected sky voltage when one side is connected to earth ground, and the other is connected to the sky collector, such as a kite or balloon with a foil collector and fine wire running down to the ground. A collector 200 300 ft high can develop a sky to ground potential as high as 20,000 volts. ref Popular Science magazine, Electrostatic Motors You Can Build , May 1971, p95 97 p114. Direct link to cited article, scanned by Google Books http books.google.com books?id ngAAAAAAMBAJ&pg PA95 ref Sky voltage and the electrical neutral wire Sky voltage was a problem for early ... current. These suspended wires also acted as sky voltage collectors, and could result in dangerous .... In order to safely dissipate this collected sky voltage, one current carrying wire of the electrical ... to discharge and bleed off any large voltage charges being collected from the suspended wires. This wire is called the neutral , since its voltage is zero relative to the earth ground. Modern three ... to absorb the sky voltage and prevent electrostatic buildup in the other poly phase current transporting ... electricity DEFAULTSORT Sky Voltage Category Electrostatics Category Atmosphere ... more details
orphan date September 2008 Wikify date April 2010 Voltage Droop control Droop droop is the intentional loss in output voltage from a device as it drives a load. Employing droop in a Voltage regulator voltage regulation circuit increases the headroom for load transients. Although it may seem counterproductive, a series resistor is included between the regulator output and the load. The resistance needs to be chosen so that at maximum output current, the output voltage at the load is the minimum acceptable. Conversely, when the output current is near zero, the voltage is near the maximum. This follows simply from Ohm s law . The behaviour of the system with and without the added droop resistor is as follows Image Droop behaviour.png In a regulator not employing droop, when the load is suddenly increased very rapidly i.e. a transient , the output voltage will momentarily sag. Conversely, when a heavy load is suddenly disconnected, the voltage will show a peak. The output decoupling capacitors have to absorb these transients before the loop has a chance to compensate. A diagram of such transients is shown below. The maximum allowed voltage swing in such a transient is math V max V nom math . Image Regulator no droop.png Comparing this to a regulator with droop, we find that the maximum allowed swing has doubled it is now math V max V min math . This increased tolerance to transients allows us to decrease the number of output capacitors, or get better regulation with the same number of capacitors. Image Regulator droop.png References http www.maxim ic.com appnotes.cfm appnote number 993 Maxim IC application note http www.canadiancontrols.com documents technical Speed 20Droop 20and 20Power 20Generation.pdf speed droop and power generation Intersil Application Note 1021 June 2002 Category Electrical parameters Category Electronics terms ... more details
good article A voltage doubler is an electronic circuit which charges capacitors from the input voltage and switches these charges in such a way that, in the ideal case, exactly twice the voltage is produced ... an AC voltage as input and output a doubled DC voltage. The switching elements are simple diodes and they are driven to switch state merely by the alternating voltage of the input. DC to DC voltage ... than relying on the voltage across the switch as in the simple AC to DC case. Voltage doublers are a variety of voltage multiplier circuit. Many but not all voltage doubler circuits can be viewed ... voltage multiplication. Voltage doubling rectifiers Villard circuit File Villard circuit.svg 150px ... on the negative half cycles to the peak AC voltage V sub pk sub . The output is the superposition ... V sub F sub , the small forward bias voltage of the diode by the diode, therefore the positive ... File Greinacher circuit.svg 200px left thumb Figure 2 . Greinacher circuit The Greinacher voltage ... voltage in the output. File Voltage quadrupler.svg thumb right 240px Figure 3 . Voltage quadrupler ... 30 ref The concept in this topology can be extended to a voltage quadrupler circuit by using two ... Bridge voltage doubler.svg thumb left 200px Figure 4 . Bridge Delon voltage doubler The Delon circuit uses a Topology electronics Bridge topology bridge topology for voltage doubling. This form of circuit ... an Extra high tension e.h.t. voltage supply. Generating voltages in excess of 5 kV with a transformer ... and white television sets required an e.h.t. of 10 kV and colour sets even more. Voltage doublers were used to either double the voltage on an e.h.t winding on the mains transformer or were ... of the incoming waveform. Since their outputs are in series, the output is twice the peak input voltage ... 5. Switched capacitor voltage doubler achieved by simply switching charged capacitors from parallel to series It is possible to use the simple diode capacitor circuits described above to double the voltage ... more details
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