Laying a power cable in the ground (in trenches) is more economical. To do this, use cables armored with iron tapes with an outer cover of cable yarn. There may be less than 6 of them in one trench. The clear distance between the cables should be from 100 to 250 mm. If the cables belong to different organizations, then this distance is increased to 0.5 m.

The depth of laying the cable with voltage up to 35 kV from the planning mark should be more than 0.7 m, and at the intersection of roads - 1 m, but more than 0.5 m from the bottom of the drainage ditch. If these distances cannot be maintained, then the cables are laid in pipes or separated from each other by a fireproof partition.

Distances (dimensions) from cable lines to engineering structures and places of objects are normalized. So, for example, it is impossible to lay cables closer than 0.6 m from the foundations of buildings; 0.5 ... 1 m - from pipelines; 2 m - from heating mains; 3 ... 10 m - from steel roads; 1 m - from the ditches of roads; 10 m - from the axis of the last wire and from the overhead line support above 1 kV; 1 m - from the overhead line support to 1 kV, etc.

If the cables intersect with engineering structures, then, starting from the size, mechanical protection of the cables is installed. In most cases, this cable is laid in pipes. These pipes must allow the replacement of cables without disturbing the normal operation of the structure crossed by the line.

If the cables are laid earlier than the structure is being built, then empty pipes are laid next to them for new cables in case of damage to the existing ones.

In cases where it is unrealistic to withstand the dimensions, the cables are also laid under a strong improved coating in pipes and blocks. This is a less economical method of cabling. Blocks are completed from asbestos-cement concrete and clay pipes or from special prefabricated reinforced concrete structures.

In blocks, 10% of spare pipes or channels are foreseen, but more than 1. When turning the route and at the transition points, more than 10 cables are arranged in the ground with special wells. The same wells are arranged on straight sections of pipes or blocks. The distance between them depends on the allowable effort when pulling the cable.

In blocks with a length of more than 50 m, lays unarmored cables with a thickened lead hermetic sheath (for example, SGT). In sections up to 50 m long, armored cables without external covers can be used.

A line with more than 6 cables should be laid in channels; and more than 20 in tunnels. Removable plates are laid over the channels. Outside buildings and in explosive installations, channels are covered with sand or soil.

In channels up to 0.9 m deep, cables can be placed on the bottom; in the deeper channels and tunnels - on cable structures. The height of the tunnel should be more than 1.5 ... 1 m, and the passage between the structures - more than 1 m. There may be local narrowing of the passages up to 0.8 m for a length of up to 0.5 m. Automatic fire extinguishing devices and smoke notifications are installed in the tunnels. To combat the ingress of water into the tunnel, automatic drainage mechanisms are made, etc. Tunnels, where, in addition to cables, there are other communications (water supply, heating system, etc.), are called collectors.

In all cable structures (tunnels, channels, collectors), unarmored cables are allowed. In switchgears, armored cables with non-combustible coating should be used. Protective covers made of combustible fibrous materials on cables laid in structures are not allowed. To prevent corrosion and best heat loss, the armor is painted in a dark color.

Support structures for cable laying are installed every 0.8 ... 1 m. Glassine, roofing felt, etc. are laid between unarmored cables with an iron hermetic sheath and support (fixing) structures. soft materials.

In industrial premises, cables are laid so that they are accessible for repair, and openly laid, for example, on trays, for inspection. In places where mechanical damage is likely, the cables are also protected everywhere at a height of up to 2 m. In the floor and interfloor coatings, cables are laid in pipes or ducts. Embedding cables in the structure of the structure ("embedding") is not allowed.

In other respects, cable laying in industrial premises is similar to cable wiring. The difference is that in this case, not only unarmored cables are used, but also cables with armor without protective covers made of combustible materials. In addition, the cable section is not limited. Cable route under water, for example, at the intersections of rivers, canals, bays, etc. choose in areas with a bottom and banks that are not sufficiently prone to erosion. Cables are buried by 0.5 ... 1 m. Underwater obstacles are bypassed or trenches and passages are foreseen in them.

Cables crossing streams, their floodplains and drainage ditches are placed in pipes embedded in the ground. In this case, use the same cables as when laying in the ground.

Without pipes under water, cables are laid in a lead sheath with armor made of flat or round wires with an external protective coating. Cables with rubber (plastic) insulation and hermetic sheath made of vinylite. Cables with paper-oil insulation and duralumin hermetic sheath are not suitable for underwater laying.

When crossing rivers with a fast current, it is necessary to use cables with double armor made of round wires, which perfectly perceive significant tensile loads. It is allowed to cross non-navigable and non-alloyable rivers with a slow flow by cables with tape armor. The exit of the cable from the water is done with a margin of 10 ... 30 m in pipes, in wells.

In drying peat bogs for cable laying, a route of neutral soils is poured 1.5 m on both sides of the last cables. Above and below the cable there should be a soil layer of more than 0.3 m. It is possible to lay the cable in pipes, blocks or closed trays above the swamp 0.3 m above the water level. All these structures are reinforced to piles.

In areas of permafrost, a number of unfavorable causes operate: cracks, heaving, subsidence, landslides, etc. Cables are laid in these areas, also with the deepest seasonal freezing underground: in trenches (up to 4 cables), in embankments, cable trays, channels and collectors; or above the ground; open on the surface (air suspension), in protective boxes, overpasses, in galleries, along the walls and structures of engineering structures and under fixed footbridges.

Trenches are arranged in rocks (at a depth of more than 0.4 m), dry sands and other soils with minor frost cracks and low heaving. In other cases, in trenches it is necessary to use cables with a hermetic duralumin sheath and stronger armor made of flat wires (AP, AARP).

Cables with tape armor are allowed when performing a number of measures to combat uneven heaving of the soil and frost cracks: embankment, backfilling of trenches with sandy or gravel-pebble soil, installation of drainage ditches or slots, seeding the cable route with grasses or planting shrubs and snow retention. All this is very expensive and labor intensive.

In areas with active development of hills, heaving and landslides, cables are not laid directly in the ground at all. Channels and underground cable trays are made watertight.

Above-ground cable laying with up to 20 of them is created on wooden, and more than 20 - on reinforced concrete flyovers. In especially difficult conditions (endless permafrost, polar night and low temperature), cables are laid along the side surfaces of the ducts of heating networks, water supply and other devices.

I. I. Meshcheryakov

Alsera performs all types of work related to the laying of power cables:

• laying power cable in trenches (including punctures under roads)
• laying of power cable on cable racks, in cable ducts
• installation of power on the facades of buildings and structures
• arrangement of overhead cable lines

Having vast experience in this field and having our own material and technical base, we guarantee the Customer high-quality performance of work within the time frame clearly indicated by the Contract. The work is carried out by qualified specialists under the constant supervision of the responsible foreman of the site. Our employees have all the permissions and permits necessary to carry out the work.

We carry out a comprehensive supply of cable and wire products and all materials necessary for the production of work. Own transport department will ensure prompt delivery of materials to the site.

When contacting our company, we guarantee the prompt solution of the tasks, starting with the preparation of estimates and ending with a laboratory report. To draw up a commercial offer for the professional installation of a power cable, you can send the terms of reference, project, or diagrams to us by mail [email protected], or call an engineer to the facility.

Departure of our engineer to the object (within the Moscow Ring Road) - free of charge!

The cost of laying the power cable

Photos of works:

Contact us at the phone number listed in the "Contacts" section, and you will receive a durable and reliable power cable that will provide you with uninterrupted power transmission to any point!

The cost of laying a cable in Moscow and the Moscow region depends on the type of installation, the amount of work and the complexity of the task. Electricians-MSK offers a full range of services for laying power cables and wiring. The use of modern technologies and equipment, as well as the high qualifications of our employees, allow us to set an acceptable cost for cable laying and guarantee the impeccable quality of the tasks.

The cost of laying a power cable and types of work

The cost of installing power cables directly depends on the chosen laying method. Employees of the Electricians-MSK company, having access groups for all types of work, perform:

• External cable routing, the cost of which is significantly lower compared to the price of flush-mounted installation. In this case, the wire is fastened with staples and staples.
• Concealed installation. Cable laying, the price of which is indicated in our price list, involves chasing walls and laying cables in hot-smoked partitions. The wire will be hidden from prying eyes, inaccessible to children and pets.
• Laying the cable in the cable channel. The best option for an office, a shopping center, a summer house: the cable is placed in a special box, and the owner of the premises can easily add an additional wire to the cable channel or repair the wiring.
• Trench installation of a power cable (a specific method of underground laying of a power wire is described in the project).
• Installation of overhead lines using porcelain insulators and stretch marks.
• Laying of low-voltage cables (telephone, TV, alarm wires, etc.).

Price list for cable installation:

Installation of electrical cables is carried out in strict accordance with the requirements of the Rules for the installation of electrical installations by qualified specialists. All work has a lifetime warranty. If necessary, our employees will assist in the process of drawing up project documentation and obtaining the necessary permits, as well as help to purchase all the necessary equipment and consumables.

Electricity plays an important role in human life. It is delivered to every home or office with power cables. And then the internal wiring provides electricity to individual rooms. Cable laying and installation are carried out by different methods. Each method has specific requirements. For example, the room temperature should be from -20ºС to +40ºС.

Wire Installation Basics

The main point in the performance of electrical types of work and not only is the availability of project documentation compiled by government agencies. The installation of the cable must take place in accordance with certain requirements, which depend on the location and conditions of installation.

For example, a special type of cable is used for outdoor and underground. The design engineer is responsible for the design and search for the installation site of electrical networks. At the same time, he must take into account not only safe laying options, but also the personal preferences of the customer. Consider the methods of laying cables in detail.

outdoor

Experts say that this is the cheapest and fastest way. If the wire gets damaged, then its repair does not require much effort. The cable is mounted on the walls using special brackets. This method is not very popular, so you can rarely find it.

Concealed wire routing

Before installing the cable, it is necessary to perform wall chasing.

Such a process consists in making the width of which depends on the type of cord being laid. This method gives the room not only a neat appearance, but is also quite safe. It has its positive and negative sides. The benefits include:

• lack of wires on the walls;
• inaccessibility for children and animals;
• protection of the wire from moisture and mechanical damage.

Installers note only one drawback of this method. This is a high probability to stumble upon the cable during the drilling process. To prevent this from happening, it is necessary to have a power supply project. Damage to the wire makes it difficult to repair.

Gasket in box

Installation of wires and cables in this way can be found in office premises, country houses, shops and enterprises.

There are two types of boxes: with an opening lid and sealed. To give a more pleasant appearance, corners and tees are additionally purchased. This method does not take much time and effort. The size of the box depends on the amount of wire being laid. If necessary, cables can be easily accessed and repaired.

underground laying

Installation of a power cable in this way requires significant funds for earthworks. The cable can be laid through a special tunnel or simply buried. At the same time, the degree of its protection depends on the power supply project.

The operating conditions of the cable must also be taken into account. Earthworks are carried out manually or with the help of equipment (depending on how deep the trench is needed).

Air laying

Installation of electrical cables is carried out by air from pole to pole in two ways:

• on porcelain insulators - connection from the pole to the house occurs with the help of a porcelain insulator;
• with the help of stretching - laying and installation of wires occur with the help of a lanyard, cable, ties and clamps. The first device is used to attach the cable and adjust the degree of tension. Its size and thickness depend on the weight and length of the cable. To deliver it to the top of the pillar, use a belt and claws.

Gasket temperature

Any cables are laid only at a positive temperature, regardless of the type of insulation and voltage. If it becomes necessary to install at a negative temperature, then the soil should first be warmed up. Why do they do it?

The paper insulation is impregnated with a special oil, which, under the influence of negative temperatures, loses its viscosity and lubricity. If it is not warmed up, cracks may occur at the bends in the cable. In addition, the cable composition will not lubricate the paper, but stick together, which will lead to its rupture. In any case, negative temperatures will affect the destruction of the material, and, consequently, will lead to a decrease in electrical strength.

Indoors it is allowed to lay cables without heating. Moreover, the temperature range is in the range from minus twenty to zero degrees Celsius.

Mounting the cable sleeve

Consider the most popular types of these elements and their purpose.

They will protect the coupling from mechanical damage. Another type is sling-connecting couplings. They serve to limit differences in levels of power cables with impregnated paper insulation.

Conclusion

In order to provide a building or structure with electricity, it is necessary to correctly lay the power cables. There are many methods for this, for example, underground and air. There are also ways to install indoors. Installation of cables takes place after the preparation of project documentation. This procedure is carried out by design engineers. The whole process is controlled by state authorities in the field of electricity supply. Various connectors serve as connecting elements. They can connect both cables to each other and be attached to various electrical appliances of high and low power.

So, we found out how the installation of electrical cables and wires is carried out.