HOW AN ELECTRICAL CABLE IS MADE

The world of electricity can be very complicated. But what about electricity do we in fact know? Well, we do know electrical cables are designed to carry current from one element to another. What we DON’T know is how an electrical cable is even made. Of course, as always, I am here to help with any confusion!

An electrical cable consists of conductors, which is an uninsulated wire suitable for carrying electrical current. Electrical conductors are made up of metals such as, copper, aluminum, etc. Most wires are made out of copper because it conducts electricity with high flexibility and very little resistance.

Electrical wires come in solid core, stranded, or braided together to form a single assembly, where the ends connect to two devices, therefore, allowing the electrical signals to transfer from one device to the other.

The first stage in the manufacturing process of a conductor is the wire-drawing. The wire-drawing consists of reducing the diameter of the wire gradually to fit its final diameter to increase conductivity. After the diameter is reduced, the wire is drawn further to decrease the diameter of the wire to the size needed for each kind of conductor.

In the second stage of this process, the wires undergo a heat treatment called annealing. Annealing is a process of heating metal and allowing it to cool slowly in order to remove internal stresses and toughen the metal. The reason of this treatment it to increase the conductivity of the wire.

Now we need insulation. Because the current runs along the outside of the copper wires, there needs to be inner conductor insulation. Insulation is the layer of synthetic materials which are applied over conductors for electrical isolation between other wires, conductive surfaces, or from the ground. An inner conductor insulation also prevents any current leakages.

Because cables sometimes contain several different wires wrapped together in an insulator, the cable may require additional elements in order to improve protection. For instance, electrical coverings called “screens” insulate the signals that circulate in the cable, shielding the power cables to prevent them from external interference. Once the cable’s inner insulation is applied, the cable then requires outer insulation called the jacket. The “jacket” is applied over the conductor insulations for mechanical, environmental, chemical, and electrical protection.

Depending on the characteristics required for the cable, PVC, the most common thermoplastic insulation may be used (SJTW cords) or rubber (SJ cords).