For the wires used in the home, copper core wires are basically used at this stage. The earliest aluminum wires have been basically replaced, and rarely appear in home decorations. But you will find that some overhead wires outside are basically made of aluminum cores. So why not use copper wire for outdoor wires? This article will answer specific questions about the selection of outdoor wire materials.
Why not use copper wire for outdoor wires? Copper wire conducts electricity better, so why use aluminum wire?
Why aren’t the outside cables indicated here made of copper wires, but of aluminum wires? Yet, the conductivity of copper wire is significantly superior to that of aluminum wire. What causes this to occur? That is, you are still unfamiliar with the installation conditions of outside wire circuits. Five reasons for this situation will be told so that everyone can understand.
The characteristics of overhead lines determine the use of aluminum wires
- For overhead lines, you will know that the wires are hung in the air by means of poles or towers. There are specifications for the weight of the wires since overhead circuit cables are hanging in the air. Aluminum actually has the second-highest conductivity, behind copper. Aluminum’s conductivity is roughly two-thirds that of copper, while its density is only one-third that of copper. As a result, in the overhead state, aluminum wire is preferable.
- Outdoor wires are also affected by their own gravity and environmental influences. The simplest point, for example, will be impacted by changes in air and temperature, which is our ordinary thermal expansion and contraction. The ability of the aluminum wire to withstand thermal expansion and contraction is better than that of copper wire, so it is more suitable to use aluminum wire for overhead wires.
The unique characteristics of aluminum wires under outdoor conditions determine the use of aluminum wires
- Aluminum wires are more suitable for outdoor overhead exposed wires. It does so because, when exposed to the elements, the aluminum wire will create a thick oxide film. In this way, corrosion and oxidation by air and rainwater are avoided. Moreover, the oxide film has good corrosion resistance and a certain degree of insulation. Hence, aluminum wires are more extensively employed in outdoor circuits.
- After the copper wire is laid bare outdoors, it cannot form a dense oxide film. As the copper wire increases in service life, layers of copper rust layers that affect current transmission may appear. So copper wire is not very suitable for bare outdoor overhead wires.
Aluminum wire’s cost influences whether it is more appropriate for usage on a big scale.
- Aluminum wire is significantly less expensive than copper wire. At this point, the price per ton of copper may be close to 80,000 yuan, while the price of aluminum is about half that, ranging from 20,000 to 30,000 yuan. Therefore, considering the price, copper wires are not used for outdoor wires. Because the amount of outdoor wires is too large, and its cost is also very high.
- Given that China requires a significant amount of overhead wires, we will undoubtedly opt for more appropriate and cost-effective materials from an investment standpoint. Aluminum wire is thus our first choice. In actuality, this holds true for numerous nations around the globe.
From the perspective of anti-theft, aluminum wires are more suitable for outdoor wires
- You may have the opinion that when they see copper and aluminum, the first thing they take is copper so you may not pay attention to aluminum. Copper cables are commonly stolen, and aluminum wires are typically unwelcome. This is because copper wires are more expensive and aluminum wires are cheaper. Therefore, the use of aluminum wires outdoors can also be anti-theft to a certain extent.
- So when you choose the corresponding material, you need to consider many special features. For example, when you want to consider wire anti-theft, you must consider people’s perceptions of this material. At this stage, the aluminum wire is even less known by the public. Frequently, no one is aware of aluminum wire.
The traits of outdoor wires also establish that they are primarily aluminum wires
Because the outside is a high-voltage wire, the voltage is extremely high, but the current is extremely low. Then in the case of fixed electric energy, the effect is actually that the voltage and current are reduced after the voltage increases. Because this is the transmitted power is fixed. Therefore, the aluminum wire fully meets the electrical conductivity of the outdoor wire, so there is no need to use copper wire.