subject: Two Commonly Used Metals in Electrical Wiring [print this page] Two Commonly Used Metals in Electrical Wiring
Copper is one of the most commonly used metals for electrical wiring. The obvious reason being its high electrical conductivity. The conductivity of copper allows the electricity to pass through it without being much heated up. Owing to its high cost, aluminium wires started being used in place of copper wires.
Aluminium wires had been used widely in the North American residential wiring from 1960s to 1970s. The major drawback of aluminium wiring is that it requires larger conductors as compared to copper because of its greater resistivity. Aluminium conductors originally were utilized along with the wiring devices for copper wire. This could result in defective connections until devices such as breakers, receptacles, switches, splice connectors, etc. were designed to address problems with junctions between dissimilar metals, oxidization and mechanical effects with temperature increase. Therefore the standards for wiring devices were revised. Today aluminium conductors have earned its wide usage in power distribution as well as large feeder circuits; since earth has abundant deposits of aluminum, it comes cheap and serves as a good alternative majorly in large feeder circuits for heavy current loads. Due to its special properties, copper continuous to be the metal used most for electrical purposes. There are many kinds of wires derived from copper. Braided Tinsel Wire for instance, refers to a low voltage electrical wire fabricated using copper by wrapping a number of copper foil strands around textile core. It is highly flexible and is known to have resistant against metal fatigue. Since it offers an excellent service Braided Tinsel Wire has become very popular. Copper Tin Wire is another product. Since rubber-insulated cables tend to become brittle as a result of exposure to oxygen; copper tinned wire is now used in its place.
Rubber has other disadvantages such as when switches or light fixtures are replaced; tightening connections cause insulation to flake off conductors. Apart from this, rubber is hard to separate from copper. Copper Tin Wire, thus became a popular substitute. Tinned copper wire is used as overhead power source in subways, light as well as heavy transit systems. There are a large number of manufacturers providing Aluminium Wire, Copper Tinned Wire, Braided Tinsel Wire and Bunched Tin Coated Wire in India. With the increase in the demand, the number of manufacturers and suppliers are also increasing day by day.
