Repair and installation works: laying the cable in the ground

If before the power transmission lines, including the cable of high-voltage lines, as well as telephone lines were mounted at a height, to the poles, then in the last decades they began to lay underground. So, the airspace was cleared above the settlements, the wires were protected from the negative impact of the environment, their safety and integrity were no longer dependent on the unraveling elements or invasions of the avian packs. The underground method of laying was technically and economically more profitable and productive.

Land-installation works

When planning to lay a power or telephone cable under the ground, it must be remembered that not all wires fit this type of operation. The cables you select must meet the required standards of insulation and protection, resistance and power.

Cable laying in the ground requires certain rules:

• Cable is better to choose armored, respectively, brand "VBshSHV" or "VBshShVng." Their advantage lies in the fact that they are enclosed in a steel protective tape, which reliably keeps them from damage of a mechanical nature, from earth rodents and exposure to moisture from groundwater.
• Cable laying in the ground should be carried out on sites that are not littered with large tree roots. It is desirable to carry out such works on the terrain cleared from extraneous objects (or so that the distance from the place of laying to the nearest trees was not less than a meter). In addition, the wires should not lie under the terrain on which heavy loads are seen: parking spaces for cars, buildings under construction, etc.
• Laying the cable in the ground, if it is conducted near residential or other buildings, should be separated from the objects by not less than 60 centimeters. Laying the cable under the foundation is strictly prohibited. You can not have your communications intersect with other existing communication lines and engineering networks. It is better to conduct them in parallel or distantly from each other.
• Having outlined the main ways, where the cable should lie, according to the scheme it is necessary to excavate a trench. So, the laying of the telephone cable can be done at a depth of 80 centimeters to one meter in free terrain. If communications should be laid in places of increased soil exploitation, the depth of the trench must be at least 1, 25 / one and a half meters;
• All the soil must be cleaned of earth and construction debris - stones, branches, etc., so that they do not interfere with the work and do not threaten damage to the wires.
• In the excavated trench you need to make a "pillow": pour a layer of sand of centimeters to the bottom at 12-14. It must necessarily cover the bottom evenly and be of the required thickness.
• The laying of the power cable, more precisely, the choice of its type, depends on the power of the electrical network, which is supposed to be installed, from the needs of consumers in energy. All settlement work is done in advance. When the right amount of wire is purchased, if it is located under areas with increased load, it should be additionally protected. To do this, it is placed in special protective "case-cases" made of pipes of the brand "HDPE".
• Further, the cable laying in the ground is conducted along the trench, without stretching. It is especially important that the slackle and the allowance are present in the wavy lines. Protective cases are stacked in advance. To ensure a high-quality power supply or telephone line signal, the cable must be solid rather than lumpy.
• When laying in one trench more than one cable, each of them must be separated from the other by at least 10 centimeters.
• The places where the cable will come out to the surface must be identified so that they can be easily detected.
• Having finished the laying, the cable is again covered with sand - the upper "pillow", the thickness of which is from 10 centimeters.
• "Pillow" is filled with soil and is rammed. The layer of the earth is from 17-20 centimeters.
• Above the entire length of the conduit, an alarm tape is laid, then the trench is finally buried, the rammed, the ground is leveled.
• The last stage of laying the cable in the ground is the repeated measurement of resistance, checking for the presence / absence of a short circuit and the earthing of the armor.

When the main earthworks are finished, everything is checked, you can start wiring the cables inside the building and connecting to the electrical or telephone network of the corresponding devices.