Wednesday, 21 January 2015

Insulator And Conductor


An electrical conductor is one body in contact with a body charged with electricity transmitted it to all points of its surface. Generally elements, alloys or compounds with free electrons that allow movement of loads.

For a material is considered good driver is required that has a low resistance or resistivity to avoid high voltage drops and excessive losses by the Joule effect.

For transporting electric power as well as for any installation of domestic or industrial use, the universally used metal is copper cables as one or more threads. Alternatively the aluminum metal is used although it has an electrical conductivity of the order of 60% of copper is, however, a much lighter material, which favors its use in transmission lines power.

the material with low electrical conductivity is called insulator . Although there are quite insulating bodies or drivers, but better or worse conductors are widely used materials to prevent short circuits, lining them electrical conductors, to keep away from the user certain parts of electrical systems, accidentally touched when in voltage, can produce a discharge, and for making insulators, elements used in electricity distribution networks to set their supports drivers with no electrical contact. The most frequently used are plastics and ceramics.

The behavior of insulators is due to the potential barrier that exists between the valence and conduction bands which hinders the existence of free electrons capable of conducting electricity through the material.

An electrically insulating material has a theoretically infinite resistance. Some materials, such as air or water, are insulators under certain conditions but not others. The air, for example, at room temperature and insulation under conditions of signal frequency and relatively low power, can become conductive.