Types of electric cables and their use

Aerial cables: These cables are used with steel harness in places where it is necessary to hang the cable on electric poles. In aerial cables, a stranded wire made of galvanized steel is used parallel to it, and a sheath made of polyethylene material is used on them.

Ground cables: < /b>These types of cables are used to transmit electricity from inside the soil. Ground cables often have a copper conductor and insulation and a P.E.T sheath, and if necessary, it is reinforced with steel tape.

Construction cable: This type of cable that is used everywhere It is found that the cables are made of copper conductors and PVC sheaths.

Electrical cable generally consists of three main parts, which include cable insulation, cable conductor and cable sheath. Of course, some cables may not have a sheath. Cables have special differences in terms of internal structure and are divided into several categories. The most common classification of cables in terms of their internal structure is as follows:

• Protodor cable: Protodor cable is used when there is a need for a cable to transmit and distribute electricity up to 1 kW in various factories and networks.
• Marine cable: This cable is a type of Protodor cable that is used to transmit electrical energy up to 10 kilowatts from the bed of rivers and seas.
• Cable with plastic insulation:< /b> Although this type of cable is not produced today, but it was used in tension.
• Cable with paper insulation: Cable with paper insulation has many uses in construction and networks. .
• Cable with lead sheath: This type of cable also has many applications, the most important of which are in gas stations, refineries and oil storage areas.
• Cable with aluminum insulation: When it is a cable to transmit energy through the ground, the cable with aluminum insulation is the best choice.

In terms of pressure and voltage level, electric cables can be divided into different groups with various applications, the most important of which are as follows:

These types of cables are made with copper or aluminum conductors and XLPE insulation and can withstand higher voltages of 36,000 watts (the maximum capacity they can withstand is 23,000 volts. Of course). XLPE (cross-linked polyethylene) insulation is injected on the copper or aluminum conductor of the power cable. This is done using a CCV line which is controlled by a computer. This insulation must be completely uniform and free of any impurities and voids. XLPE insulation chemically and physically has a great tendency to form a chain with water molecules, so if there is water or its vapor in the insulation layer, it will reduce the electrical resistance of the insulation.

• High voltage high voltage cables can withstand electric current up to 400,000 volts. These cables are known as EHV.

Low voltage cable is a group of electrical cables that withstand voltage levels of 600 to 1000 volts and include copper and aluminum cables that are insulated with different polymers. These cables have various applications in the transmission of electrical energy, including creating lighting and moving power to electric motors. Low pressure cables can be divided into different types based on the type of use they are used for, including fire-resistant cables (for sensitive environments where fire extinguishing is very important), flame-resistant cables (for environments with high risk of fire), cables with lead sheath, armored cables (creating electrical protection), halogen-free cables and a number of other cables.

Building cables are responsible for the distribution of electricity in the building, which have different structures. Among the most important construction cable structures, the following can be mentioned:

Flexible cable whose conductor must be of flexible type and its insulation is of PVC or rubber type, whose PVC insulation can be 70 degrees or 90 degrees Celsius.

Heat Resistant cable is another type of building cable whose conductor is flexible and its insulation is made of Silicon Rubber. These cables will withstand heat up to 180 degrees and Class Fiber Braid coating is used to increase its resistance against mechanical damage.

As its name suggests, the fireproof cable must have a high resistance to fire. These cables are usually used in public places that use emergency systems. These cables must not transmit fire, continue to burn, or create smoke.

Type of conductor: The most common conductors in the electric cable industry are copper and aluminum with high purity (over 99 percent), which are used in annealed or non-annealed form. (annealing is a heat treatment that causes recrystallization of metal crystals). This operation causes the conductor wire to become flexible and soft during the mechanical stretching and rolling operations. divided into three different categories, which is almost similar to the division based on the number of strands. and is known as a class one conductor.

Conductor strand: It is called class two and is obtained by twisting several simple wires around each other. In this conductor, some strings can not bend; Like 7 central strands in a 37 or 61 strand conductor. The number of strands forming a stranded conductor is usually 7, 19, 37, 61, 91 strands. Several strands of thin annealed wire that are irregularly twisted together (bunched) and used to produce flexible insulated wires or flexible cables.