What Are Different Elements Of A Cable?

Conductor

A conductor is a current-carrying element, made of aluminum or copper, with a specific cross-section of a specified rating and a resistance per kilometer within a specific specified range.

Electrical insulation (dielectric)

Insulation is provided on the conductors to electrically isolate them from each other. The various insulating materials used are: PVC, XLPE (cross-linked polyethylene), rubber, etc.

The insulated conductor is called the core. A cable may have one or more cores. In a multi-conductor cable, the core wires are helically twisted together. In two-core, three-core and multi-core cables, the cores are laid together with the appropriate lay length; the outermost layer is laid in the right direction, and subsequent layers are laid in the opposite laying direction.

Inner sheath (bedding)

Stranded core cables are provided with an inner jacket and can be applied by extrusion or wrapping. Make sure the shape is as round as possible. The application of the inner jacket makes it a snug fit over the laid core wire and it should be possible to remove it without damaging the insulation. The thickness of the inner sheath is specified in the relevant standard and is based on the calculated diameter of the laminated core.

Armor

A type of wire, strip, or tape that is helically wound around a cable to protect it from sharp objects, crushing forces, and damage from rodents or drilling insects, known as armor.

In the case of single-core cables, the armor is over the insulation, and in the case of twin-, triple-, and multi-core cables, the armor is over the inner jacket.

Outer sheath

The outer sheath/jacket is usually an extruded plastic cover over the laminated or armored core. PVC is a common sheath material. The outer sheath provides mechanical, thermal, chemical and environmental protection. No electrical function is assigned to the outer sheath. The color of the outer sheath is usually black.