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Current Limiter
Current limiting is the practice of imposing a limit on the current that may be delivered to a load to protect the circuit generating or transmitting the current from harmful effects due to a short-circuit or overload. The term "current limiting" is also used to define a type of overcurrent protective device. According to the 2020 NEC/NFPA 70, a current-limiting overcurrent protective device is defined as, "A device that, when interrupting currents in its current-limiting range, reduces the current flowing in the faulted circuit to a magnitude substantially less than that obtainable in the same circuit if the device were replaced with a solid conductor having compatible impedance." Inrush current limiting An inrush current limiter is a device or devices combination used to limit inrush current. Passive resistive components such as resistors (with power dissipation drawback), or negative temperature coefficient (NTC) thermistors are simple options while the positive one (PTC) is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Fault Current Limiter
A fault current limiter (FCL), also known as fault current controller (FCC), is a device which limits the prospective fault current when a fault occurs (e.g. in a power transmission network) ''without'' complete disconnection. The term includes superconducting, solid-state and inductive devices. Applications Electric power distribution systems include circuit breakers to disconnect power in case of a fault, but to maximize reliability, they wish to disconnect the smallest possible portion of the network. This means that even the smallest circuit breakers, as well as all wiring to them, must be able to disconnect large fault currents. A problem arises if the electricity supply is upgraded, by adding new generation capacity or by adding cross-connections. Because these increase the amount of power that can be supplied, all of the branch circuits must have their bus bars and circuit breakers upgraded to handle the new higher fault current limit. This poses a particular problem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Electric Current
An electric current is a flow of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is defined as the net rate of flow of electric charge through a surface. The moving particles are called charge carriers, which may be one of several types of particles, depending on the Electrical conductor, conductor. In electric circuits the charge carriers are often electrons moving through a wire. In semiconductors they can be electrons or Electron hole, holes. In an Electrolyte#Electrochemistry, electrolyte the charge carriers are ions, while in Plasma (physics), plasma, an Ionization, ionized gas, they are ions and electrons. In the International System of Units (SI), electric current is expressed in Unit of measurement, units of ampere (sometimes called an "amp", symbol A), which is equivalent to one coulomb per second. The ampere is an SI base unit and electric current is a ISQ base quantity, base quantity in the International System of Qua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Fault (power Engineering)
In an electric power system, a fault is a defect that results in abnormality of electric current. A fault current is any abnormal electric current. For example, a short circuit in which a live wire touches a neutral or ground wire is a fault. An open-circuit fault occurs if a circuit is interrupted by a failure of a current-carrying wire (phase or neutral) or a blown Fuse (electrical), fuse or circuit breaker. In a "ground fault" or "earth fault", current flows into the earth. In Three-phase electric power, three-phase systems, a fault may involve one or more phases and ground, or may occur only between phases. In a polyphase system, a fault may affect all phases equally, which is a "symmetric fault". If only some phases are affected, the resulting "asymmetric fault" becomes more complicated to analyse. The analysis of these types of faults is often simplified by using methods such as symmetrical components. The prospective short-circuit current of a predictable fault can be calcul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Electric Current
An electric current is a flow of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is defined as the net rate of flow of electric charge through a surface. The moving particles are called charge carriers, which may be one of several types of particles, depending on the Electrical conductor, conductor. In electric circuits the charge carriers are often electrons moving through a wire. In semiconductors they can be electrons or Electron hole, holes. In an Electrolyte#Electrochemistry, electrolyte the charge carriers are ions, while in Plasma (physics), plasma, an Ionization, ionized gas, they are ions and electrons. In the International System of Units (SI), electric current is expressed in Unit of measurement, units of ampere (sometimes called an "amp", symbol A), which is equivalent to one coulomb per second. The ampere is an SI base unit and electric current is a ISQ base quantity, base quantity in the International System of Qua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Analog Circuits
Analogue electronics () are electronic systems with a continuously variable signal, in contrast to digital electronics where signals usually take only two levels. The term ''analogue'' describes the proportional relationship between a signal and a voltage or current that represents the signal. The word ''analogue'' is derived from the Greek word meaning ''proportional''. Analogue signals An analogue signal uses some attribute of the medium to convey the signal's information. For example, an aneroid barometer uses the angular position of a needle on top of a contracting and expanding box as the signal to convey the information of changes in atmospheric pressure. Electrical signals may represent information by changing their voltage, current, frequency, or total charge. Information is converted from some other physical form (such as sound, light, temperature, pressure, position) to an electrical signal by a transducer which converts one type of energy into another (e.g. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Electrical Ballast
An electrical ballast is a device placed in series with a load to limit the amount of electric current, current in an electrical network, electrical circuit. A familiar and widely used example is the inductive ballast used in fluorescent lamps to limit the current through the tube, which would otherwise rise to a destructive level due to the negative resistance, negative differential resistance of the tube's voltage-current characteristic. Ballasts vary greatly in complexity. They may be as simple as a resistor, inductor, or capacitor (or a combination of these) wired in series with the lamp; or as complex as the electronic ballasts used in compact fluorescent lamps (CFLs). Current limiting An electrical ballast is a device that limits the current through an electrical load. These are most often used when a load (such as an arc discharge) has its terminal voltage decline when current through the load increases. If such a device were connected to a constant-voltage powe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Crowbar (circuit)
A crowbar circuit is an electrical circuit used for preventing an overvoltage or surge condition of an AC power supply unit from damaging the circuits attached to the power supply. It operates by putting a short circuit or low resistance path across the voltage output (Vo), like dropping a Crowbar (tool), crowbar across the output terminals of the power supply. Crowbar circuits are frequently implemented using a thyristor, TRIAC, trisil or thyratron as the shorting device. Once triggered, they depend on the current (electricity), current-limiting circuitry of the power supply or, if that fails, the blowing of the line fuse (electrical), fuse or tripping the circuit breaker. The name is derived from having the same effect as throwing a crowbar over exposed power supply terminals to short the output. Example In the following example crowbar circuit, the LM431 adjustable Zener_diode, zener regulator controls the gate of the TRIAC. The Voltage_divider, resistor divider of R1 and R2 p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Current Source
A current source is an electronic circuit that delivers or absorbs an electric current which is independent of the voltage across it. A current source is the dual of a voltage source. The term ''current sink'' is sometimes used for sources fed from a negative voltage supply. Figure 1 shows the schematic symbol for an ideal current source driving a resistive load. There are two types. An ''independent current source'' (or sink) delivers a constant current. A ''dependent current source'' delivers a current which is proportional to some other voltage or current in the circuit. Background , - align="center" , style="padding: 1em 2em 0;", , style="padding: 1em 2em 0;", , - align="center" , Voltage source , Current source , - align="center" , style="padding: 1em 2em 0;", , style="padding: 1em 2em 0;", , - align="center" , Controlled voltage source , Controlled current source , - align="center" , style="padding: 1em 2em 0;", , style="padding: 1em 2em 0;", , - align=" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
MOSFET
upright=1.3, Two power MOSFETs in amperes">A in the ''on'' state, dissipating up to about 100 watt">W and controlling a load of over 2000 W. A matchstick is pictured for scale. In electronics, the metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, MOS FET, or MOS transistor) is a type of field-effect transistor (FET), most commonly fabricated by the controlled oxidation of silicon. It has an insulated gate, the voltage of which determines the conductivity of the device. This ability to change conductivity with the amount of applied voltage can be used for amplifying or switching electronic signals. The term ''metal–insulator–semiconductor field-effect transistor'' (''MISFET'') is almost synonymous with ''MOSFET''. Another near-synonym is ''insulated-gate field-effect transistor'' (''IGFET''). The main advantage of a MOSFET is that it requires almost no input current to control the load current under steady-state or low-frequency conditions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Lamp Inrush Current
Lamp, Lamps or LAMP may refer to: Lighting * Oil lamp, using an oil-based fuel source * Kerosene lamp, using kerosene as a fuel * Electric lamp, or light bulb, a replaceable component that produces light from electricity * Light fixture, or light fitting or luminaire, is an electrical device containing an electric lamp that provides illumination * Signal lamp, or Aldis lamp or Morse lamp, a semaphore system for optical communication * Safety lamp, any of several types of lamp that provides illumination in coal mines ** Davy lamp Arts, entertainment and media Film and television * ''The Lamp'' (1987 film), or ''The Outing'', a horror film * ''The Lamp'' (2011 film), an American drama * ''Lamp'' (advertisement), a 2002 television and cinema advertisement for IKEA Music * Lamp (band), a Japanese indie band * "Lamp", a song by Bump of Chicken from the 1999 album '' The Living Dead'' Literature * ''Lamp'', a newspaper in Delaware * ''The Lamp'' (magazine), American bimonthl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Switched-mode Power Supply
A switched-mode power supply (SMPS), also called switching-mode power supply, switch-mode power supply, switched power supply, or simply switcher, is an electronic power supply that incorporates a switching regulator to electric power conversion, convert electrical power efficiently. Like other power supplies, a SMPS transfers power from a DC or AC source (often Mains electricity, mains power, see AC adapter) to DC loads, such as a personal computer, while converting voltage and Electric current, current characteristics. Unlike a linear power supply, the pass transistor of a switching-mode supply continually switches between low-dissipation, full-on and full-off states, and spends very little time in the high-dissipation transitions, which minimizes wasted energy. Voltage regulator, Voltage regulation is achieved by varying the ratio of on-to-off time (also known as duty cycle). In contrast, a linear power supply regulates the output voltage by continually dissipating power in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
