Electricity nowadays has become a complete necessity for us to carry on our daily lives, as we are totally reliant on electrical devices whether we are working or handling simple tasks both indoors and outdoors.
Electricity passes through metallic conductors that are formed into different shapes and types of electric cables and wires, such as Aluminum and Copper cables. Metals are known for their excellent electrical conductivity as they have free electrons on their outer surface, allowing the electrical current to pass smoothly through them with minimal resistance.
Each metal has its own conductivity based on its atomic structure, and the higher the conductivity, the lesser the resistance that faces the electric current while passing through this metal, and thus the higher the intensity of current that can pass through this cable at the same voltage.
Brief on electric cables
They are the connectors that link the power source to the devices that are meant to work using the voltage generated by the source, so these cables transfer electricity in the form of electric current that has a specific intensity that is affected by the voltage of the source and the resistance of the electric circuit.
The higher the intensity of the current in the cables, the more devices that can be function by it, and the more possible it is to make devices like air conditioners work as they require a high intensity of current to function.
To achieve a high intensity of current, the power source should be of high voltage or the resistance of the circuit should be lower. As for the resistance, it can be lowered through the use of cables with a larger cross sectional surface area and also by using highly conductive metals such as Copper.
As for the disadvantages of having cables of high resistance, they are that they hinder the electric current and lower its intensity, thus requiring higher voltage sources in order to run devices with high intensity requirements. In addition, when transferring electric current over long distances, the greater the resistance of the travelling cables, the greater the amount of power lost. As power is transformed in the cables into heat through their journey and the more resistant the cables are the higher the amount of power is lost in the form of heat.
Types and structure of electric cables
An electric cable is usually made in a cylindrical shape with different layers; the innermost layer is the metallic fibers that are responsible for carrying the electric current, and it is usually covered by an insulating material. This is a simple cable, but in cases of more complex cables, it is further enveloped by either an auxiliary material as a shield to enhance its longevity or an extra outer PVC layer for extra insulation. The cable can be made of one core and thus called a mono-conductor, or it can be made of multiple cores and called a multi-conductor.
Cables can be classified into many categories according to the point of differentiation, as they can be sorted according to their voltage and usage into low, medium, and high voltage cables. Or they can be sorted according to their arrangement inside the cable sheath, whether arranged in many cores in different patterns or in a single core with variant sorts as well.
Copper is considered the standard metal for measuring conductivity as it has the highest conductivity to electricity after silver, which is more expensive and harder to use in cabling. It is of high tensile strength, which means it is less likely to break when exposed to stretch, force, wear, and tear, whether by the effect of time or while being installed, which makes it preferable due to its ease of installation. As well, it is of small diameter, so it doesn't necessitate large raceways, in addition to having a low thermal expansion factor, so it doesn’t enlarge and lengthen much by the effect of heat.
Because of its high specifications, copper became the most commonly used metal in cabling, despite the fact that nothing is perfect. Copper has barely few disadvantages, such as being expensive compared to its alternatives as well as heavyweight when compared to the substitutes, thus posing difficulties in installation to some extent, especially for long distances, as it necessitates the presence of support for heavy-weighted cables.
Aluminum is an abundant metal that is commonly available in nature as it is one of the most present elements in the earth's crust. As a metal, Aluminum is a good conductor that can be used in cabling, and thanks to its availability, it has a cheap price when compared to copper, as in some circumstances it could cost around half the cost. Furthermore, because Aluminum is light-weighted, it can be used over long distances without the need for support, and it is malleable, allowing it to be easily formed into different shapes and patterns.
While the major downsides of Aluminum cables are that they require around twice the cross-sectional area of copper to conduct the same intensity of electricity and have around 60% conductivity when compared to copper, larger raceways are required for their installation. As well, it is of less tensile strength, so it is more likely to break, and when oxidized, it becomes non-conductive, which can heat it up. It also has a high thermal expansion factor, which means its connections can loosen with heat cycles, which can cause fire risks. And it is more liable to corrosion, so a special compound should be used to avoid this, and due to its high resistivity, it causes high drops in voltage in long runs, which can cost a lot in transferring power over really long distances.
What is better, Aluminum or Copper cables?
As previously stated, each of them has its own advantages and disadvantages, so if you were comparing both of them and trying to decide which would be the best choice for you, it is recommended that you look up your budget first, as the main difference that plays a major role here is cost. For example, in cases of tight budgets, aluminum can be of great use, whereas if your budget allows it, copper is by far the most cost-efficient choice due to its exquisite specifications.