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Encyclopedia > Electrical conductor

In science and engineering, conductors, such as copper or aluminum, are materials with atoms having loosely held valence electrons. See electrical conduction. Conductors are used to connect circuits to allow th circuit going Image File history File links Broom_icon. ... A magnet levitating above a high-temperature superconductor demonstrates the Meissner effect. ... Engineering is the discipline of acquiring and applying knowledge of design, analysis, and/or construction of works for practical purposes. ... For other uses, see Copper (disambiguation). ... Aluminum is a soft and lightweight metal with a dull silvery appearance, due to a thin layer of oxidation that forms quickly when it is exposed to air. ... Conduction is the movement of electrically charged particles through a transmission medium (electrical conductor). ...

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Note: The following applies to direct current only. When the direction of voltage/current alternates, other effects (inductance and capacitance) come into play also. Direct current (DC or continuous current) is the continuous flow of electricity through a conductor such as a wire from high to low potential. ... An electric current i flowing around a circuit produces a magnetic field and hence a magnetic flux Φ through the circuit. ... Capacitance is a measure of the amount of electric charge stored (or separated) for a given electric potential. ...


All conductors contain movable electric charges which will move when an electric potential difference (measured in volts) is applied across separate points on a wire (etc) made from the material. This flow of charge (measured in amperes) is what is meant by electric current. In most materials, the amount of current is proportional to the voltage (Ohm's law) provided the temperature remains constant and the material remains in the same shape and state. The ratio between the voltage and the current is called the resistance (measured in ohms) of the object between the points where the voltage was applied. The resistance across a standard mass (and shape) of a material at a given temperature is called the resistivity of the material. The inverse of resistance and resistivity is conductance and conductivity. Electricity (from New Latin Ä“lectricus, amberlike) is a general term for a variety of phenomena resulting from the presence and flow of electric charge. ... The volt is the SI derived unit for electric potential and voltage (derived from the ampere and watt). ... For the acoustic law, see Ohms acoustic law. ... Electrical resistivity (also known as specific electrical resistance) is a measure of how strongly a material opposes the flow of electric current. ...


Most familiar conductors are metallic. Copper is the most common material for electrical wiring, and gold for high-quality surface-to-surface contacts. However, there are also many non-metallic conductors, including graphite, solutions of salts, and all plasmas. See electrical conduction for more information on the physical mechanism for charge flow in materials. This article is about metallic materials. ... For other uses, see Graphite (disambiguation). ... For other meanings of the word salt see table salt or salt (disambiguation). ... For other uses, see Plasma. ... Conduction is the movement of electrically charged particles through a transmission medium (electrical conductor). ...


Non-conducting materials lack mobile charges, and so resist the flow of electric current, generating heat. In fact, all materials offer some resistance and warm up when a current flows. Thus, proper design of an electrical conductor takes into account the temperature that the conductor needs to be able to endure without damage, as well as the quantity of electrical current. The motion of charges also creates an electromagnetic field around the conductor that exerts a mechanical radial squeezing force on the conductor. A conductor of a given material and volume (length x cross-sectional area) has no real limit to the current it can carry without being destroyed as long as the heat generated by the resistive loss is removed and the conductor can withstand the radial forces. This effect is especially critical in printed circuits, where conductors are relatively small and close together, and inside an enclosure: the heat produced, if not properly removed, can cause fusing (melting) of the tracks. The electromagnetic field is a physical field that is produced by electrically charged objects and which affects the behaviour of charged objects in the vicinity of the field. ... Close-up photo of one side of a motherboard PCB, showing conductive traces, vias and solder points for through-hole components on the opposite side. ...


Since all conductors have some resistance, and all insulators will carry some current, there is no theoretical dividing line between conductors and insulators. However, there is a large gap between the conductance of materials that will carry a useful current at working voltages and those that will carry a negligible current for the purpose in hand, so the categories of insulator and conductor do have practical utility.


Thermal and electrical conductivity often go together (for instance, most metals are both electrical and thermal conductors). However, some materials are practical electrical conductors without being a good thermal conductor.


Power engineering

In power engineering, a conductor is a piece of metal used to conduct electricity, known colloquially as an electrical wire. This article or section does not cite its references or sources. ... Electrical wiring in general refers to conductors used to carry electricity, and their accessories. ...


Conductor size

In many countries, conductors are measured by their cross section in square millimeters.


However, in the United States, conductors are measured by American wire gauge for smaller ones, and circular mils for larger ones. American wire gauge (AWG), also known as the Brown and Sharpe wire gauge, is used in the United States and other countries as a standard method of denoting wire diameter, especially for nonferrous, electrically conducting wire. ...


Conductor materials

Of the metals commonly used for conductors, copper, has a high conductivity. Silver is more conductive, but due to cost it is not practical in most cases. However, it is used in specialized equipment, such as satellites, and as a thin plating to mitigate skin effect losses at high frequencies. Because of its ease of connection by soldering or clamping, copper is still the most common choice for most light-gauge wires. For other uses, see Copper (disambiguation). ... Not to be confused with electrical conductance, a measure of an objects or circuits ability to conduct an electric current between two points, which is dependent on the electrical conductivity and the geometric dimensions of the conducting object. ... This article is about the chemical element. ... For other uses, see Satellite (disambiguation). ... The skin effect is the tendency of an alternating electric current (AC) to distribute itself within a conductor so that the current density near the surface of the conductor is greater than that at its core. ... (De)soldering a contact from a wire. ...


Conductor voltage

The voltage on a conductor is determined by the connected circuitry and has nothing to do with the conductor itself. Conductors are usually surrounded by and/or supported by insulators and the insulation determines the maximum voltage that can be applied to any given conductor. International safety symbol Caution, risk of electric shock (ISO 3864), colloquially known as high voltage symbol. ... This article or section is in need of attention from an expert on the subject. ...


Conductor ampacity

The ampacity of a conductor, that is, the amount of current it can carry, is related to its electrical resistance: a lower-resistance conductor can carry more current. The resistance, in turn, is determined by the material the conductor is made from (as described above) and the conductor's size. For a given material, conductors with a larger cross-sectional area have less resistance than conductors with a smaller cross-sectional area. American wire gauge (AWG), also known as the Brown and Sharpe wire gauge, is used in the United States and other countries as a standard method of denoting wire diameter, especially for nonferrous, electrically conducting wire. ... In electricity, current refers to electric current, which is the flow of electric charge. ...


For bare conductors, the ultimate limit is the point at which power lost to resistance causes the conductor to melt. Aside from fuses, most conductors in the real world are operated far below this limit, however. For example, household wiring is usually insulated with PVC insulation that is only rated to operate to about 60 °C, therefore, the current flowing in such wires must be limited so that it never heats the copper conductor above 60 °C, causing a risk of fire. Other, more expensive insulations such as Teflon or fiberglass may allow operation at much higher temperatures. 200 A Industrial fuse. ... Polyvinyl chloride Polyvinyl chloride, (IUPAC Polychloroethene) commonly abbreviated PVC, is a widely used thermoplastic polymer. ... For other uses, see Fire (disambiguation). ... Teflon is a trademark of DuPont and is commonly used for the chemical compound polytetrafluoroethylene. ... Bundle of fiberglass Fiberglass (also called fibreglass and glass fibre) is material made from extremely fine fibers of glass. ...


The American wire gauge article contains a table showing allowable ampacities for a variety of copper wire sizes. American wire gauge (AWG), also known as the Brown and Sharpe wire gauge, is used in the United States and other countries as a standard method of denoting wire diameter, especially for nonferrous, electrically conducting wire. ...


Isotropy

If an electric field is applied to a material, and the resulting induced electric current is in the same direction, the material is said to be an isotropic electrical conductor. If the resulting electric current is in a different direction from the applied electric field, the material is said to be an anisotropic electrical conductor. In physics, the space surrounding an electric charge or in the presence of a time-varying magnetic field has a property called an electric field. ... This box:      Electric current is the flow (movement) of electric charge. ...


See also

Electrical resistivity (also known as specific electrical resistance) is a measure of how strongly a material opposes the flow of electric current. ... A charge transfer complex (CT complex) is defined as an electron donor–electron acceptor complex, characterized by electronic transition(s) to an excited state. ... In power engineering, a bundle conductor is a number of conductors in parallel. ... A magnet levitating above a high-temperature superconductor, cooled with liquid nitrogen. ...

References

Wikimedia Commons has media related to:
Electrical conductors
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  Results from FactBites:
 
electrical conductor (130 words)
Most non-metals are poor conductors; however, there are exceptions such as plasma.
The electrons in conductors lie in a so-called conduction band that, in an energy diagram, sits on top of the valence band.
A material can be an electrical conductor without being a thermal conductor, although most metals are both.
Electrical conductor terminating arrangements - Patent 5548088 (2571 words)
An electrical conductor terminating arrangement as claimed in claim 5, characterized in that the collet comprises a split tubular metal part which has a conductor-receiving end, with said tubular metal part adapted to be radially inwardly compressed to make good electrical contact with the conductor.
An electrical conductor terminating arrangement as claimed in claim 5, characterized in that said terminating arrangement includes a pin contact and in which the split tubular metal part (31) is formed integrally with said pin contact at an end of the split tubular metal part remote from the conductive compressible clamping means.
An electrical conductor terminating arrangement as claimed in claim 7, characterized in that the clamping means comprises a sleeve member and the collet has a split frusto-conical section (33) that is engaged by said sleeve.
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