Any material that can help the electric current through it is called a conductor. Metals are considered to be better conductors rather than other substances. Metals are composed of oppositely charged atoms that are tightly packed to form a fixed shape and volume. How much current is drawn through the metal depends on the conductor type. Most common conductor types that are used in cable manufacturing is copper and aluminum. Both materials possess different resistances (R) based on the following factors.
Where the constant is called resistivity of the material which is different for every material. ‘L’ represents the length of the conductor. ‘A’ represents the area of the conductor. So, resistance is very key concept to decide which conductor type should be used in cable manufacturing as it defines the conductivity ( of the material. Reciprocal of resistivity gives conductivity.
Different cables are manufactured using different conductor types. Some of these are discussed as follows: –
- Solid Conductors
The solid conductors used in cable manufacturing involves a single wire of copper or aluminum having a circular cross-sectional area.
- Stranded Conductors
The stranded conductors used in cable manufacturing involves several thin wires of copper or aluminum having very small circular cross-sectional area. However, it is further divided into three more conductor types based on the placement of conductor in the cable.
1. Concentric-Stranded Conductor
In the Concentric stranded conductor, each conductor is placed in a concentric pattern i.e. there is feasible space among the three wires of the conductors.
2. Compressed Stranded Conductor
In this stranded conductor type, the distance between the wires and conductors is squeezed out. The stranded conductor is totally compressed with the outer insulation of the wire and there is no space between the wires of the conductors.
3. Compact Stranded Conductor
The wires are first shaped in a trapezoid and then are combined eliminating every possible space between the wires. It is the most compact form having lesser space and lesser diameter relatively to all other stranded conductor types.