Electrical Cable

Electrical Cable

Electrical cable is an assembly of two or more electrical conductors, usually held together with an overall sheath. The assembly is used for transmission of electrical power.

Electrical cables may be installed as permanent wiring within buildings, buried in the ground, run overhead, or exposed.

Electrical cables come in a variety of sizes, materials, and types, each particularly adapted to its uses. Large single insulated conductors are also sometimes called power cables in the industry.

Cables consist of three major components: conductors, insulation and protective jacket. The makeup of individual cables varies according to application. The construction and material are determined by three main factors:

  • Working voltage, determining the thickness of the insulation;
  • Current-carrying capacity, determining the cross-sectional size of the conductor(s);
  • Environmental conditions such as temperature, water, chemical or sunlight exposure, and mechanical impact, determining the form and composition of the outer cable jacket.

Cables for direct burial or for exposed installations may also include metal armor in the form of wires spiralled around the cable, or a corrugated tape wrapped around it. The armor may be made of steel or aluminum, and although connected to earth ground is not intended to carry current during normal operation.

Power cables use stranded copper or aluminum conductors, although small power cables may use solid conductors. The cable may include uninsulated conductors used for the circuit neutral or for ground (earth) connection.