Electric cable

Electric cables. Cable is called a conductor (usually copper or aluminum) or a group of them generally covered with an insulating or protective material, although the name cable is also used for light transmitters (fiber optic cable) or mechanical stress (cable mechanical) .They are materials whose resistance to the passage of electricity is very low. The best electrical conductors are metals, such as copper, gold, iron and aluminum, and their alloys, although there are other non-metallic materials that also have the property of conducting electricity, such as graphite or saline solutions and solutions ( for example, sea water) or any material in a plasma state. For the transport of electrical energy, as well as for any installation for domestic or industrial use, the best conductor is silver, but due to its high price, the materials commonly used are copper (in the form of single or multi-strand cables), or aluminum; Although metal has an electrical conductivity of the order of 60% of that of copper, it is nevertheless a three times lighter material, which is why its use is more indicated in overhead electric power transmission lines in high voltage networks. . Contrary to popular belief, gold is slightly less conductive than copper, yet it is used in battery terminals and electrical connectors due to its durability and “resistance” to corrosion. The electrical conductivity of pure copper was adopted by the International Electrotechnical Commission in 1913 as the standard reference for this quantity, establishing the International Annealed Copper Standard. commonly used materials are copper (in the form of single or multi-strand cables), or aluminum; Although metal has an electrical conductivity of the order of 60% of that of copper, it is nevertheless a three times lighter material, so its use is more indicated in overhead electric power transmission lines in high voltage networks. . Contrary to popular belief, gold is slightly less conductive than copper, yet it is used in battery terminals and electrical connectors due to its durability and “resistance” to corrosion. The electrical conductivity of pure copper was adopted by the International Electrotechnical Commission in 1913 as the standard reference for this quantity, establishing the International Annealed Copper Standard. commonly used materials are copper (in the form of single or multi-strand cables), or aluminum; Although metal has an electrical conductivity of the order of 60% of that of copper, it is nevertheless a three times lighter material, so its use is more indicated in overhead electric power transmission lines in high voltage networks. . Contrary to popular belief, gold is slightly less conductive than copper, yet it is used in battery terminals and electrical connectors due to its durability and “resistance” to corrosion. The electrical conductivity of pure copper was adopted by the International Electrotechnical Commission in 1913 as the standard reference for this quantity, establishing the International Annealed Copper Standard. or aluminum; Although metal has an electrical conductivity of the order of 60% of that of copper, it is nevertheless a three times lighter material, so its use is more indicated in overhead electric power transmission lines in high voltage networks. . Contrary to popular belief, gold is slightly less conductive than copper, yet it is used in battery terminals and electrical connectors due to its durability and “resistance” to corrosion. The electrical conductivity of pure copper was adopted by the International Electrotechnical Commission in 1913 as the standard reference for this quantity, establishing the International Annealed Copper Standard. or aluminum; Although metal has an electrical conductivity of the order of 60% of that of copper, it is nevertheless a three times lighter material, so its use is more indicated in overhead electric power transmission lines in high voltage networks. . Contrary to popular belief, gold is slightly less conductive than copper, yet it is used in battery terminals and electrical connectors due to its durability and “resistance” to corrosion. The electrical conductivity of pure copper was adopted by the International Electrotechnical Commission in 1913 as the standard reference for this quantity, establishing the International Annealed Copper Standard. reason why its use is more indicated in overhead electric power transmission lines in high voltage networks. Contrary to popular belief, gold is slightly less conductive than copper, yet it is used in battery terminals and electrical connectors due to its durability and “resistance” to corrosion. The electrical conductivity of pure copper was adopted by the International Electrotechnical Commission in 1913 as the standard reference for this quantity, establishing the International Annealed Copper Standard. reason why its use is more indicated in overhead electric power transmission lines in high voltage networks. Contrary to popular belief, gold is slightly less conductive than copper, yet it is used in battery terminals and electrical connectors due to its durability and “resistance” to corrosion. The electrical conductivity of pure copper was adopted by the International Electrotechnical Commission in 1913 as the standard reference for this quantity, establishing the International Annealed Copper Standard. It is used in battery terminals and electrical connectors due to its durability and “resistance” to corrosion. The electrical conductivity of pure copper was adopted by the International Electrotechnical Commission in 1913 as the standard reference for this quantity, establishing the International Annealed Copper Standard. It is used in battery terminals and electrical connectors due to its durability and “resistance” to corrosion. The electrical conductivity of pure copper was adopted by the International Electrotechnical Commission in 1913 as the standard reference for this quantity, establishing the International Annealed Copper Standard.

(International Standard for Annealed Copper) or IACS. According to this definition, the conductivity of annealed copper measured at 20 ° C is equal to 58.0 MS / m. This value is what is called 100% IACS and the conductivity of the rest of the materials is expressed as a certain percentage of IACS. Most metals have conductivity values ​​less than 100% IACS, but there are exceptions such as silver or special very high conductivity coppers designated C-103 and C-110. [3]

Summary

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  • 1 Classification of electrical conductors (Cables)
    • 1 Voltage Level
    • 2 Components
    • 3 Number of drivers
    • 4 Materials used
    • 5 Conductor insulation
    • 6 Insulating materials
  • 2 uses
  • 3 Resistance of electrical conductors
  • 4 See also
  • 5 Source

Classification of electrical conductors (Cables)

Electric cables can be subdivided according to:

Voltage level

  • very low voltage cables (up to 50 V).
  • low voltage cables (up to 1000 V).
  • medium voltage cables (up to 30 kV).
  • high voltage cables (up to 66 kV).
  • very high voltage cables (above 770 kV).

Components

  • Conductors (copper, aluminum or other metal).
  • Insulations (plastic, elastomeric materials, paper impregnated with viscous or fluid oil).
  • Protections (screens, armor and covers).

Number of conductors

  • Unipolar: Single conductor.
  • Bipolar: 2 conductors.
  • Tripolar: 3 conductors.
  • Tetra polar: 4 conductors

Materials employed

  • Almelec (Aluminum alloy, Magnesium).

Conductor insulation

  • Thermoplastic insulation:
  • PVC – (polyvinylchloride). • PE – (polyethylene). • PCP – (polychloroprene), neoprene or plastic.
  • Thermoset insulation:
  • XLPE – (crosslinked polyethylene). • EPR – (ethylene-propylene). • MICC – Mineral-insulated copper-clad cable.

Insulating materials

  • Impregnated paper cables:
  • Paper impregnated with non-migratory mixture. • Paper impregnated with fluid oil.
  • Cables with extruded polymeric insulation:
  • Crosslinked polyethylene (XLPE) • Ethylene propylene rubber (HEPR) • High-density thermoplastic polyethylene (HDPE). [2]

Applications

The main applications of an electrical conductor are the transport of electrical energy (household electrical grid cables, high voltage cables, electrical appliances, actuators, lighting, automobiles, etc.), signal transport (transmitters / receivers, computers, automobiles, etc.), and manufacture of electronic components (connectors, printed circuit boards, resistors, capacitors, transistors, integrated circuits, sensors, etc.).

  • Conduct electricity from one point to another (pass electrons through the conductor; electrons flow due to the potential difference).
  • Create electromagnetic fields by constituting coils and electromagnets.
  • Modify the voltage when constituting transformers.

Resistance of electrical conductors

Every electrical conductor affects the passage of an electric current to a greater or lesser degree determined by its resistance, which is affected by the following factors: The metal of which it is formed, thickness and length. Silver is the metal that conducts electricity more easily, but given its high cost, it is not common to use it as a conductor in electrical circuits. Copper is the most widely used conductor for its low cost, apart from being a good conductor of electricity. Aluminum is also used. But this has the drawback that it cannot be welded by common means, therefore its use in houses is very limited, only in high voltage transmission lines. When we measure the resistance of different pieces of metal, of the same size and thickness ,

  • Silver (6.8)
  • Copper (6.0)
  • Gold (4.3)
  • Aluminum (3.8)
  • Brass (copper with 30% by weight of zinc) (1.6)
  • Iron (1.0)
  • Platinum (0.94)
  • Carbon steel (0.6)
  • Stainless steel (0.2)

The “siemens” (symbol “S”), is the conductance unit G in the International System of Units. Conductance is the inverse of resistance (G = R-1), and since siemens is equivalent to ohm-1, it is sometimes misnamed “mho” (ohm written backwards!) Or using the Greek letter W (omega uppercase) drawn backwards! (no comments …) When it is required to transport electricity with the minimum loss, metals are used that, in addition to being good conductors, are reasonably cheap (not like silver or gold). So, the first candidates are copper (Cu) and aluminum (Al). Indeed, thick copper and sometimes aluminum conductors are used in industry. Copper used as a conductor is actually a material called “electrolytic copper,” with 99.92 to 99. 96% by weight of copper. In this alloy, 0.03% oxygen improves its density and conductivity. There are position switches, where a certain amount of liquid mercury joins two contacts, closing an electrical circuit. Many boards and electrical devices also contain “bronze to aluminum” conductors, an alloy of 88 to 96% copper with tin, iron, and 2 to 10% aluminum. This material has much more mechanical and chemical resistance than electrolytic copper, necessary in switches where sparks raise the temperature of the material. The following list shows approximate values ​​of the electrical resistivity r (the inverse of the conductivity: r = s-1) at 20 ° C and at 10-8 ohm xm, of some metals used in electrical devices: 03% oxygen improves its density and conductivity. There are position switches, where a certain amount of liquid mercury joins two contacts, closing an electrical circuit. Many boards and electrical devices also contain “bronze to aluminum” conductors, an alloy of 88 to 96% copper with tin, iron, and 2 to 10% aluminum. This material has much more mechanical and chemical resistance than electrolytic copper, necessary in switches where sparks raise the temperature of the material. The following list shows approximate values ​​of the electrical resistivity r (the inverse of the conductivity: r = s-1) at 20 ° C and at 10-8 ohm xm, of some metals used in electrical devices: 03% oxygen improves its density and conductivity. There are position switches, where a certain amount of liquid mercury joins two contacts, closing an electrical circuit. Many boards and electrical devices also contain “bronze to aluminum” conductors, an alloy of 88 to 96% copper with tin, iron, and 2 to 10% aluminum. This material has much more mechanical and chemical resistance than electrolytic copper, necessary in switches where sparks raise the temperature of the material. The following list shows approximate values ​​of the electrical resistivity r (the inverse of the conductivity: r = s-1) at 20 ° C and at 10-8 ohm xm, of some metals used in electrical devices: where a certain amount of liquid mercury joins two contacts closing an electrical circuit. Many boards and electrical devices also contain “bronze to aluminum” conductors, an alloy of 88 to 96% copper with tin, iron, and 2 to 10% aluminum. This material has much more mechanical and chemical resistance than electrolytic copper, necessary in switches where sparks raise the temperature of the material. The following list shows approximate values ​​of the electrical resistivity r (the inverse of the conductivity: r = s-1) at 20 ° C and at 10-8 ohm xm, of some metals used in electrical devices: where a certain amount of liquid mercury joins two contacts closing an electrical circuit. Many boards and electrical devices also contain “bronze to aluminum” conductors, an alloy of 88 to 96% copper with tin, iron, and 2 to 10% aluminum. This material has much more mechanical and chemical resistance than electrolytic copper, necessary in switches where sparks raise the temperature of the material. The following list shows approximate values ​​of the electrical resistivity r (the inverse of the conductivity: r = s-1) at 20 ° C and at 10-8 ohm xm, of some metals used in electrical devices: an alloy of 88 to 96% copper with tin, iron, and 2 to 10% aluminum. This material has much more mechanical and chemical resistance than electrolytic copper, necessary in switches where sparks raise the temperature of the material. The following list shows approximate values ​​of the electrical resistivity r (the inverse of the conductivity: r = s-1) at 20 ° C and at 10-8 ohm xm, of some metals used in electrical devices: an alloy of 88 to 96% copper with tin, iron, and 2 to 10% aluminum. This material has much more mechanical and chemical resistance than electrolytic copper, necessary in switches where sparks raise the temperature of the material. The following list shows approximate values ​​of the electrical resistivity r (the inverse of the conductivity: r = s-1) at 20 ° C and at 10-8 ohm xm, of some metals used in electrical devices:

  • Silver (1.6)
  • Copper (1.7)
  • Gold (2.2)
  • Aluminum (2.7)
  • Tungsten (tungsten) (5.51)
  • Platinum (10.6)
  • Aluminum Bronze (11)
  • Tin (11.5)
  • Lead (20.7)
  • Mercury (96)

 

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