Aluminum cable, like any other, has a number of basic characteristics. This list includes such parameters as the material and cross section of the core, the material for insulation and the number of wires in the core.
First characteristic
So, the core material refers to the first parameter. In everyday life, people most often resort to the use of three main cables: copper, aluminum and aluminum-copper. If we talk about the aluminum cable, then we can highlight such positive qualities as cheapness, light weight, good electrical conductivity, good heat transfer, resistance to chemical influences.
However, there are some drawbacks to this wire:
- Very low material flexibility. If you bend the aluminum wire several times in the same place, it will break. From this it follows that the operation of this type of cable is acceptable only in stationary installations without sharp corners, turns, etc.
- Oxidation in contact with air. During the interaction of air and this metal, aluminum oxide appears. This is a very refractory black film that covers the core. The trouble is that the oxide is a complete dielectric. For this reason, electric current practically does not pass in the places of film formation.
- Aluminum is considered a good conductor, but this is only if the material is clean, that is, does not contain impurities. This is currently very difficult to achieve.
The second parameter is the section
The cross section of the aluminum cable is a rather important characteristic that applies to any type of conductor. If we talk about wires in general, then their cross section can be in the range from 0.3 to 800 mm 2 . However, it is worth saying that it is not recommended to use such wires in everyday life. The most common cross section is from 0.35 to 16 mm 2 . Rarely, but still used cables with a cross section of 25 mm 2 .
In order to determine which section is necessary in a particular wiring, it is necessary to be based on the strength of the current and the voltage that will be on the network. The dependence of these parameters is very simple. The thicker the cable section, the greater the conductivity it has. Another small but important characteristic of a cable with aluminum conductors is their number. Depending on this indicator, the flexibility of the entire wire as a whole will change. The dependence of this characteristic is as follows - the more veins per section, the more flexible the wire will be.
Insulation
If you choose the most important characteristic of aluminum cables, then this will be an insulating material. It is this element that determines what qualities the wire will have. Depending on the insulation, these types of cables are distinguished: armored, heat-resistant, waterproof, pressure-protected, etc. Since electric current is a real danger to human life, the issue of cable insulation is an important part of its operation. However, it is worth saying here that isolation is needed not only to protect a person, but also to protect the conductor itself. This is best seen if there is multi-core wiring.
Insulation task and dielectric strength
If we talk about the main tasks of insulation, then they can include the following: protection against leakage, as well as from electric shock, thermal and mechanical protection of the cable itself, indication of conductors. It is worth noting that there are a lot of materials used for insulation, as well as types of insulation. To consider all species, it will take a huge amount of time, besides this makes no sense. It is best to determine those that are applicable in the domestic environment.
There are currently two main types. The first is TPG - a conductive core, as well as a sheath covering the core from the outside. The main parameter by which the material for insulation is selected is electric strength. This parameter can be described as follows: this is the value of the current strength, which will be enough for it to break through a layer of insulating material with a thickness of 1 mm. It is worth noting that all the cables that are used in domestic conditions have enormous electrical strength, and therefore punching of electric current is possible only in case of mechanical damage to the cable insulation itself.
Heat resistance
The second characteristic of the insulating material used to cover the aluminum cable is heat resistance. Everything is quite simple here: the higher this value, the higher the heating temperature the material can withstand without losing its properties. This is a rather important quality, since everyone knows that when an electric current passes, the conductor heats up. If the value is not large enough, the insulating material will melt. This also includes such qualities of the wire as resistance to frost and mechanical strength. Naturally, the stronger and more stable the tensile insulation, the better.
One of the most common insulation materials today is polyvinyl chloride (PVC). This product demonstrates the best qualities when opposing alkalis and other acids. The disadvantages of this material include the fact that it has a rather low resistance to frost - only up to -20 degrees Celsius.
Power cable with aluminum conductors
These cables are mainly used in high voltage power lines. It is worth noting that at elevated temperatures the value of the voltage bandwidth of such a cable does not change. However, with the opposite effect, that is, with a decrease in temperature, the throughput will also decrease. Power aluminum cable is quite widespread due to the fact that it is characterized by low cost. However, it also has a small weight, even with large dimensions. It is these advantages that distinguish the cable with aluminum core from the cable with copper.
However, low cost is not always good. Customer reviews and electricians are quite controversial in this regard. Yes, aluminum cables are cheaper, but their resistance is almost one and a half times greater than that of copper, for example. In other words, the disadvantage is that with the same cross section, the aluminum cable passes one and a half times less current and at the same time heats up. In order to solve this problem, you have to buy a cable with a thicker cross section.
Aluminum armored cable
Armored cable differs from the others in that, in addition to insulation, it also has a metal layer. The presence of an additional metal layer greatly increases the life of such a cable, and the conductor becomes more protected from mechanical damage.
Most often, a galvanized tape is used as a metal layer, which is wound between layers of conventional insulation. The disadvantage, of course, is the almost complete loss of cable flexibility, which becomes even more noticeable in the case of an aluminum conductor, which is initially characterized by low flexibility.