Underground electrical cable. Laying cables in a trench

Good afternoon dear friends. When connecting a summer cottage or private house to electricity, you may need to lay underground cable. The work requires contact with the electrical network, so you must act in accordance with standard safety regulations. Without knowledge of the principle of implementation and the norms for the depth of the laying, this cannot be done, so it is better to entrust such actions to a specialist. For correct installation Cable installation requires the ability to connect several pieces of cable into one network, introducing the cable into the house with mandatory insulation, and many other things that are acquired with experience. If you want to learn the skill of laying cables underground, then this article is just for you. Enjoy reading!

How to lay a cable in the ground

You can run the cable through the site underground. This is a more labor-intensive process, but more reliable in terms of safety - there is less chance that someone will borrow it. This moment is especially relevant in country houses and garden plots. But laying the cable in the ground is carried out in accordance with certain rules, prescribed in the PUE. These norms and explanations for them are set out below.

Which cables to use

If we talk about GOST, it says that it is necessary to lay armored cables in the ground, covered with a waterproofing layer on top. That is, if the allocated power is sufficiently large, it is advisable to make the underground entry into the house from the pole with an armored cable.

This is AVBbShv (armored with aluminum conductors and armor made of two galvanized steel strips, covered with a protective layer on top) or VBBbShv (the same, but with copper conductors), PvBShv - also armored, but with cross-linked polyethylene insulation and the same steel strips as armor. AAShp, AAShv, AAB2l, AAP2lShv, ASShl, etc. are suitable. These types of cable products are used in lands with normal acidity.

It is better not to use cables not intended for underground installation.

Laying cables in soil with increased chemical activity - salt marshes, swamps, a large number of construction waste, slag - requires lead armor or aluminum shell. In this case, you can use AABl, AAShv, AAB2l, ASB, AAPl, ASpl, AAP2l, AAShp, AVBbShv, AVBbShp, APvBbShv and others.

If you need to connect small dacha, in which there are absolutely no electrical appliances, a bathhouse, a barn or other outbuildings (pig sty, chicken coop, etc.)

PVC shell, as it is quite durable and definitely airtight. NYM, SIP are often used to install lighting on the site; VVG is enough for several years. But these products are not intended for installation underground and they quickly fail.

More serious cables are, of course, more expensive, but they last much longer. If we take into account the labor intensity of installation, it is more advisable to use special cables, and these are AAShv, AAShp, AAP2l, AVVG, AABL, APsVG, ASB, AAPL, APvVG, APVG, ASPL, etc.

An armored cable has three sheaths, a regular cable has one

In the regions of the Far North, special products with increased frost resistance - PvKShp - are used for underground installation.

Standards and depth for laying armored electrical cables in a summer cottage

First you need to develop a cable route. It is clear that when laying in a straight line, less of it will be required. But, unfortunately, this is not always possible. When laying a route, it is advisable to avoid:

• Walking near large trees. It is advisable to lay the route at a distance of at least a meter from large trees. If the tree is located directly on the road, it is advisable to go around it along an arc or a trajectory close to it. In principle, the optimal distance is 1.5 m. If such an arc does not fit into the site, you can dig small trenches on both sides of the tree, drive a metal pipe into the ground between them, and pull the cable into it. If there are more plants, they must be bypassed
• It is highly advisable to bypass areas with increased traffic: parking areas, access areas for sewage disposal vehicles, pedestrian paths, etc. Such zones can be bypassed along the perimeter.
• If areas with increased load cannot be bypassed, cases are used to improve protection. Cases are also needed at intersections with drainage trays, at intersections of water supply lines, gas pipelines and other communications. If there are any sections of the route with a ditch depth of less than 50 cm or in places where it was not possible to remove solid objects ( old foundation, large stones, etc.) - it is worth putting a protective case everywhere.
• If the underground cable route runs along the foundation, it must be at least 60 cm away from it. Laying the cable in the ground closer to the foundation is prohibited - movements of the soil or building can damage the power line.
• It is advisable to avoid crossing with other cables. If it is impossible to bypass the intersection, both cables must be in a case. They must protrude beyond the intersection by at least 1 meter in both directions, and the cables must be at a distance of at least 15 cm one above the other.

If you couldn’t avoid all the difficult places, don’t worry. In these areas, you can lay the cable not in the ground, but in a corrugated pipe, HDPE pipe or metal pipe. They are called cases. When using several pieces of metal pipes in a row, they must be welded. This is done so that they do not damage the shell at the junction points.

The procedure and technology for laying cables in the ground

They dig a trench along the intended route. Its depth is 70-80 cm, the width when laying one cable is 20-30 cm, when laying two or more, the distance between the threads laid at the bottom of the trench must be at least 10 cm. Use these criteria to decide. After the trench has been dug, you must:

1. Remove all hard and sharp objects, roots, stones, etc. They can damage the insulation and may cause the line to fail.
2. Level the bottom and compact it a little. It is not necessary to bring it to level, but there should not be any sudden changes.
3. Pour a 10 cm layer of sand and level it. You can use cheap sand from a quarry, but it must be sifted so that foreign objects do not get in - stones, pieces of glass, etc. Compact the sand too. You can just crush it with your feet. There should be no obvious humps or depressions.
4. Check the integrity of the insulation, if there is damage somewhere, repair it. Cases (pieces of pipes) are first put on the cable and dragged to places of increased load.
5. Next, the actual laying of the cable in the ground begins - it is laid in a trench with sand. You can’t pull it - it should lie in light waves. Cases are placed in the right places along the route. The waves will allow the line not to break during frost heaving or other ground movements
6. It is advisable to check the laid cable - damage may occur during installation. If you have a megometer, great, use it to check the integrity of the shell. If there is no such device, you can ring the wires for a break with a conventional multimeter or tester. It is also necessary to check them for ground. If it “grounds” somewhere, the insulation has been damaged. It is necessary to look for damage and repair it.
7. If all the parameters are normal, sketch out a plan for the route, preferably to scale, with reference to landmarks. Set the distances from reliable objects to the route (from the corner of the house, the edge of the plot, etc.). Laying the cable in the ground is also inconvenient because if repairs are necessary, it is difficult to gain access. If you have a plan with dimensions, everything will be much easier.
8. After this, fill the laid cable with sand. It is also sifted and a layer is poured - about 10 cm, compacted. There is no need to tamp down too much; you can compact it with your feet.
9. Next, a layer of 15-20 cm of previously excavated soil is poured. When backfilling, remove stones and other foreign objects. The layer is also leveled and compacted.
10. Lay down warning tape. This is a bright polymer tape with the inscription “be careful with the cable!” During excavation work, it can save electrical wiring laid underground from damage. The warning tape will warn in the event of possible excavation work
11. Afterwards, they continue to fill the ditch with soil, pouring it slightly above ground level, since after some time the rock will compact and settle.

AND final stage- examination electrical parameters before connecting to the load. This completes the laying of the cable in the ground. Once again, the entire procedure can be seen in the video.

Nuances and features

Laying cables in the ground is a labor-intensive process. It takes a lot to dig a trench, and then carrying the cable is also not easy. Burying is a little easier, but also not the most pleasant experience. If after a couple of years the insulation becomes leaky, you will have to repeat everything again, which will not make anyone happy.

It’s clear that it’s better to do everything once and more reliably. The fact is that you can lay the cable in a trench without a protective sheath. This will not contradict the norm. And if you install a high-quality armored cable, it will last a long time.

For greater reliability, it is advisable to lay the cable in double-walled special corrugation or asbestos-cement pipes

But if you are laying a regular VVG or NYM, for greater reliability, it is better to lay it in a double-walled corrugated hose DKS along its entire length. In the right places, you additionally put on cases made of stiffer pipes or the same booster tube but of a larger diameter.

Asbestos-cement or plastic thick-walled pipes are also often used. When laying the cable in this way in the ground, the risk of its premature failure is much lower - most of the loads fall on the pipes, and not on the protective sheath and conductors.

Laying the cable in the ground in plastic or asbestos-cement pipes or corrugated hoses has one more advantage: there is a high probability that, if necessary, it can be replaced by simply tightening it in place of the old one.

The new one is tied to the old one, the old one is pulled out, and the new one “crawls” in its place. But this is not always possible: over time, both the pipe and the corrugated hose can collapse - the effects of ice and soil loads contribute to the destruction of the protective shells.

From all this it follows that although laying cables in paper insulation does not contradict the standards, it is better to use plastic insulation - PVC or cross-linked polyethylene.

Paper, even with special impregnations, deteriorates much faster than polymers, which brings the replacement period closer. Laying cables in the ground still requires significant effort and labor, so it is better to lay more durable materials.

How to join two pieces

It is more reliable to lay the cable in the ground in whole pieces - without connections. If one piece of the required length cannot be found, to connect, bring both parts to the surface, place a sealed mounting box and connect the conductors in it.

It is not worth making couplings without experience and special equipment, or burying them underground - they will quickly fail and will have to be dug up and remade. And a serviced connection is always convenient - you can reconnect the contacts if you need to.

How to enter the house

When entering a house, bathhouse, outbuilding, passing the cable under the foundation is unacceptable. Even if it is a shallow strip foundation. In general, when pouring the tape to enter the cable into the house, mortgages are embedded in it. This is a piece of pipe that protrudes a few centimeters beyond the foundation. The cable is inserted into it.

The cross-section of this embed should be 4 times larger than the cable cross-section. And to prevent living creatures from getting into the remaining gap, after laying the mortgage is sealed. To seal, you can use the old antiquated method - a rag soaked in cement milk, or fill everything with polyurethane foam.

Entry of underground power cable through the foundation:

If a mortgage was not made during construction, you will have to drill a hole in the foundation, insert and seal a pipe. Further, all the technology is the same.

If you have not provided for a mortgage in the wall or foundation, drill a hole. Insert a pipe into the hole made, foam it, and thread a cable through it.

Another option: raise the cable in a metal pipe to a certain height along the wall of the house. They usually raise it to the level where the introductory cabinet hangs.

At this height, install a mortgage in the wall (the same metal pipe with the same parameters and rules) and lead the cable into the house through it. This method is suitable if your foundation is - monolithic slab or you just don’t want to break the monolithic nature of the tape.

How to introduce an underground cable into a house through a wall?

When using an armored cable, the armor must be grounded. To do this, a wire in a sheath is welded/soldered to the armor, and it is brought to “zero” in the shield.

If this is not done, when the phase breaks through, it will most likely end up on the armor. If someone touches the armor, at best they will receive an electrical injury, at worst they may die. If the protective metal shell is grounded (or rather, zeroed), the breakdown will trigger the machine, which will turn off the power until the causes are identified and eliminated.

If there are several cables

If several cables are laid underground at the same time, the distance between them should be at least 10 cm. If you decide to lay them in pipes or corrugated hoses, a separate one for each.

If there are several cables, they are placed each in its own sheath or simply placed in parallel at a distance of 10-15 cm from one another

How to tighten into a corrugation or pipe

There are two types of corrugations for underground cable laying - with and without a probe. It's easier to take with a probe. This is a thin wire to which the wiring is tied to tighten it inside. The wire is pulled out and the cable is tightened in its place. It's simple.

If the pipe or corrugation does not have a probe, problems may arise. If the cable is stiff enough, you can simply tuck it inside. This is usually not difficult, but can take quite a lot of time.

This trick will not work with a soft conductor - it will twist and cling to the walls. But in this case, too, there is a way out. First, string or thin rope is threaded into the pipe. A cable is tied to it and pulled inside.

How to thread the twine? Using a vacuum cleaner. Fix one edge of the twine well, and lay the rest in an unfolded form, but without lumps or loops, in the pipe. On the other side, connect the vacuum cleaner, close the second inlet. By creating a rarefied atmosphere, the string flies out from the other side.

Laying cables under the road - how to do it correctly?

If the route is located in such a way that it must be built under a road, and this is someone else’s land, then you will have to obtain permission from the organization on whose balance sheet this road is located. This point is mandatory in populated areas, since there may be other communications under the road and they can be damaged by unauthorized work. If we are talking about a dacha and a holiday village, then it must be agreed with the administration of the village.

A puncture under the road is made using special equipment

The rules for laying cables under the road do not change - trench depth is 70-80 cm, sand cushion and backfill, laying in an asbestos-cement pipe or double-wall corrugated DCS is desirable. In general, there are no differences, all the rules and regulations are the same.

Difficulties may arise if it is necessary to lay cables under asphalt. If it’s a solid road, you’re unlikely to be allowed to destroy the surface, and if they do, restoring the asphalt will be an expensive proposition.

In this case, there is also a way out - there is special equipment that is used to make a puncture under the road. The service is also not cheap, but it costs much less than the cost of asphalt restoration.

Source: http://stroychik.ru/elektrika/prokladka-kabelya-v-zemle

Laying cables underground and what kind of cable can be laid in the ground with your own hands

There are three ways to connect a private home to the street network. Air connection, underground cable laying and combined when it is difficult to use one of the previous ones independently. In this article, we will consider how to lay a cable in the ground, since we have already discussed the aerial connection method.

Advantages of underground cable laying

Let's start with the fact that laying the cable in a trench has only advantages over an air connection. Of course, if you follow the rules for such installation, it will eliminate the need to open the trench to repair or replace the cable. Let's go over the advantages of this method:

• Possibility to use a cable of the required section (with a margin) and not calculate the weight linear meter, strengthening the suspension structures;
• Possibility of minimizing external devices (installing a circuit breaker from the street network at the input is sufficient for complete shutdown);
• Aesthetics are also important, since a cable hanging over the front garden does not add attractiveness, and often limits the dimensions for vehicles;
• With sufficient depth, you can forget about the cable altogether;
• The asking price most often turns out to be lower than installation and approval overhead line connections;
• With proper design of connected communications, laying a cable underground will cost as much as the selected materials.

These are not all the advantages, but they are the main ones that are worth keeping in mind when choosing a connection method. As for technologies, they are approximately the same for all regions of Russia (unlike air), and are regulated by GOSTs, which have been used without any significant changes since the mid-60s.

Laying cables in the ground

However, it is possible to highlight the main stages of underground installation of an electrical input cable for private housing construction.

Connect to an external source. The popular name is “to the pillar”. The method of installation and assembly of the street power panel in which the meter is located is “lower” or “upper”. It is permissible to lay an underground cable without the participation of power engineers to the power switchboard of the house.

The second stage is, in fact, laying the cable in the trench and methods of protecting it. At this stage, especially if you decide to do it yourself, the main thing is to understand how to choose a cable, that is, which cable can be laid in the ground, and which should not be laid even with good protection.

This is the third stage - checking the line for suitability for operation and the decision will be made by the power engineers.

The last stage will be connecting the house network, digging trenches and connecting your home to the power grid. In a good way, if there is already electrical wiring, it is worth measuring the insulation resistance and also checking the phasing of your network.

You can stop there - laying the cable underground is completed, and you can forget for many years about how exactly electricity enters the house. There are a few examples left from life so that you don’t think that we are talking theoretically.

Power cable for outdoor installation in foreign land near a dacha

Now about what kind of cable can be laid in the ground. In this connection, a cable option was chosen that allows operation in the most difficult conditions. The length of the line is 28 meters from the shield on the pole. We bought a 50 m bay.

The rest was spent on connecting the bathhouse. The cost of saving on cable was approximately 30%. The margin of safety, of course, was huge, but the payment for this was not so great in terms of the cost of the entire project. GOSTs are good help, as well as the characteristics of the cable, but when you need to buy 2-3 dozen meters, it’s probably worth not skimping on this particular section of your personal electrical network.

Don’t forget to cover the trench at a level 20 centimeters above the cable with a “do not dig” warning tape. Sooner or later they will start digging, reach the tape and stop. The more expensive the tape, the more durable it is.

Let's return to the power engineers and try to understand why they have such strange requirements for laying cables underground.

From the power line the cable is laid in plastic. Sorry for the gaps in the photo - in villages they like to use posts for announcements. Now let's see where the input cable ends up going. The same pipe is made of an excellent alloy, which is slightly susceptible to corrosion and will not rot for a long time. It is inside this pipe that the cable is laid in the trench and connected to the house.

Of course, the question arises: why is there plastic on top and only metal below? You will be surprised, but it was precisely this requirement that raised questions from the author of the article and even some conflict with power engineers. The answer turned out to be simple and obvious. More on this below, first one more photo.

And now the answer to the question - why is there a plastic pipe from the line to the flap (before that it was metal, which was simply cut off when installing a new “lower” position flap). “When your house is on fire due to a short circuit and the circuit breakers not working, it’s easier for firefighters to take an ax and cut off the power cable than to look for who has the keys.” This is a verbatim answer from energy workers.

And this answer says a lot, so when thinking about how to lay a cable in the ground, keep in mind that power engineers have their own reasons and it is not always just a desire to make money, forcing you to order all the work from them. Both GOSTs and PUE were written for a reason, and therefore all work related to electrical wiring should be checked with what is written in them, although this is of course a very tedious task.

What you can't see underground

People can't see underground, so assume there are moles that can chew through cables, a lot of water, and corrosion. In addition, the earth “breathes”, settling in the spring and bulging in the winter, so it can freeze deeper than experts claim. That, finally, a ravine may appear underground.

All these factors can lead to an accident, so even laying cables underground must be accompanied by exact calculation and excluding all factors that can de-energize your home.

Source: http://obelektrike.ru/posts/prokladka-kabelja-pod-zemlej/

Underground cable laying: how to do it right

When electrifying a private house or cottage, you have to decide whether the route will run through the air or in the ground. Laying a cable in the ground requires more work, but it provides greater safety: it is more difficult to pull wires out from under the ground than to cut them from the cable. Therefore, despite the high cost, this method is often chosen.

We are developing the route

The route for underground cable laying from the pole to the house will be drawn for you in the project and all that remains for you is to follow all the instructions. But when distributing electricity along the site, you have to design the route yourself. Most economical option- a straight line from one point to another. But a real route like this practically never happens. Most often this is a broken line, since you have to go around many obstacles.

How to lay a route

When planning a route, you must adhere to the following rules:

• Avoid crossing with other cables. If this is not possible, the distance between the cables must be at least 15 cm (one is higher than the other). At the intersection, hard cases are put on both conductors - made of plastic water pipes or asbestos-cement pipes. You can put an asbestos pipe sawn lengthwise onto the previously laid cable, then connect it with ties or tape. Please note that the cases should protrude 1 meter on both sides of the intersection.
• When crossing water, sewer, gas pipes the distance to the cable must be at least 0.5 m if it is laid without a protective sheath, and 0.25 m if it is laid in a pipe or sheath. Moreover, the protective shell should extend 2 meters in both directions from the intersection.
• If laying cables in the ground is needed along pipelines (water, sewerage, gas), the distance to them must be at least 1 meter. When laying in pipes, the distance can be reduced to 25 cm. Large plants must be avoided: trees and even shrubs
• If the underground power supply route runs along the heating main, the distance between them must be at least 2 meters. Moreover, the heating main must be well insulated.
• You should walk around the perimeter of the parking areas and the entry points for cars (including sewage trucks). If you can’t get around them, you need to either lay the route deeper or use a hard case.
• Large trees should be walked around in a large circle with a radius of at least 2 meters or a route should be laid so that the trunk is 2 meters away. There is another option - at the required depth under the tree, drive a pipe at least 2 meters long through which to pass the cable.
• There must be at least 0.75 m from the place where the conductor is laid to the bushes.
• If the cable is laid in the ground along the foundation, the distance to it must be at least 60 cm.

Drawing a plan

Once you have a rough idea of ​​the route, transfer it to a piece of paper. This plan should also include main structures, water supply, sewerage, etc. After you dig a trench and lay the cable (before backfilling), measure the distance to all “long-term” objects and transfer them to the plan.

Cables for various purposes can be indicated by different colors

Professionals call this process “localization.” This plan with distances can be very useful later - when redeveloping the site, planning new buildings, etc. He will also be there if there is a need to repair the transmission line. According to the plan, you will restore the location of the route.

Cable protection on top

When laying a cable in the ground, there is always a high probability that it may be damaged during any excavation work. Therefore, the PUE provides for the presence of protection above the route.

Power cables (1 kW and above) require protection concrete slabs or solid brick. For low-power lines, which usually power our homes, it is allowed to lay the cable in the ground with signal plastic tapes. This method of protection is permitted if there are no more than two conductors in the trench.

Laying the cable in the ground must be accompanied by laying protective plastic tape

Signal tapes are laid along the cables at a distance of 250 mm from their outer cover. If there is only one power line, the tape is located above it; if there are two or more, two or more tapes are placed. Their edges should protrude beyond the cable by at least 50 mm, and adjacent tapes should be laid with an overlap of 50 mm.

Underground cable laying technology

Laying a cable in the ground means digging a trench along the entire route. Recommended depth - 70-80 cm.

If for some reason it is not possible to dig to such a depth, you can reduce it, but lay a line into pipes or a protective shell. This can be a corrugated hose or special pipes, the outer shell of which is made of more rigid polypropylene, and inner part- made of softer polyethylene.

You can also use asbestos-cement or plumbing plastic suitable diameters. Why not sewer? Their walls are thinner and they cannot protect against serious loads.

It is not recommended to use metal pipes, but because of their excessive rigidity: when the soil moves, their hard edge can (and often does) grind the shell. Therefore, if you lay a cable in metal pipes, you will need to weld them along the entire route and figure out how to make the edges not so hard.

The distance between the cables can be fixed using wooden pegs or pieces of foam.

If pipe cases are used on the cable route, it is better to seal their edges. So the earth will not fill in them, the water will not flood. The easiest way is to add a little foam at the edge, but you can also use cement-sand mortar or rags soaked in cement milk. Which one is more convenient? Just remember that the cable inside should not be stretched. There should be a little slack.

In addition to the depth, you also need to decide on the width of the trench. For one cable, it is recommended to be 25-30 cm wide. When laying two or more, there must be at least 100 mm of distance between them. In addition, the distance from the outer cables to the wall is at least 15 cm. In accordance with these recommendations, the width of the trench is determined.

List and order of work

Laying cables in the ground begins with excavation work. Using the marked route and selected parameters, we dig a trench, simultaneously removing all hard and sharp objects from the walls. It is advisable to make the walls with a slight slope - this way they will crumble less and work more conveniently. When the trench is ready, the order of work is as follows:

• We inspect the bottom and walls, remove all sharp and hard objects: stones, sticks, roots.
• Level and compact the bottom.
• Pour, level and compact sand. Layer thickness - at least 10 cm, but better than 15. The cheapest one is suitable, quarry sand, but it must be sifted so that there are no foreign inclusions in it. Laying cables in the ground: cross section
• The cases are laid out on the sand cushion in the right places.
• We stretch the cable. When laying, be careful not to damage the insulating layer.
• After drawing the plan, 25 cm of sand is poured on top. It is leveled and slightly compacted. You should not use a tamper; it is better to compact it with your feet. If you need to save money, you can pour a 10 cm layer of sand and fill the remaining 15 cm with soil.
• Signal tape is being laid. Please make sure that the lettering is facing up throughout.
• The top is filled with sifted soil without stones and clay. It is better to pour it in layers, compacting each layer.

This completes the laying of the cable in the ground. But there are also features and nuances.

Before laying the cable in the ground and after backfilling, it is very advisable to check the insulation resistance. For this purpose, a megohmmeter is used, which supplies high voltage, checking the quality and condition of the insulation.

After checking, do not forget to remove the residual voltage by shorting the wires to ground. This operation must be carried out with great care, since with good insulation quality and a long route, the voltage can be very considerable.

Defeat to them carries serious consequences - even death. Therefore, when working with an ohmmeter and when removing residual voltage, do not forget about dielectric gloves and glasses.

With such damage to the sheath, it is better not to use the cable for underground installation. Having repaired it, it can be used in a place more accessible for repair.

Since the ohmmeter is in household Rarely encountered, vinyl insulated cables can be checked using a conventional tester or voltmeter. They will not measure the insulation resistance, but they will show the presence of a breakdown or short between the conductors. We call all the conductors with each other, as well as each with the ground, screen or armor. If there are any problems, it is better not to use this piece.

When laying and filling with sand, make sure that the insulation is not damaged. After installation, also check the insulation or ring the wires. You probably know what happens if you apply voltage to a conductor with broken insulation.

It is better to bury a single piece of cable in the ground without connections. If this is not possible, connect the two pieces above the ground in a special installation box for the street. The box can be mounted on a post that is dug in where the cables exit to the surface. It is unwise to make homemade couplings, since they are of low quality and they are usually the source of problems.

Connecting two pieces of underground power cable in a junction box

If several lines are laid in a trench, and they must pass through a protective shell, then each should have its own shell.

How to enter the house

Entering a cable laid underground into a house can be done in several ways, but the PUE does not allow simply running it through the foundation. There are other methods:

• In a house with a basement, a hole is made on a strip foundation and a piece of metal pipe is walled into it. The edges of the pipes should protrude slightly beyond the boundaries of the foundation. The cable is pulled into this pipe and the remaining space is sealed. You can use rags soaked in cement milk, fill it with polyurethane foam, cut off the excess, then cover it with cement mortar. An example of introducing an underground cable into a house
• In the place where the underground cable approaches the house, install a curved metal pipe and pass the cable through it. At the required height, insert the wires into the house through the wall. Here you will need to monitor the bending radius - it must be at least 0 diameters of the outer shell. So bends at right angles are not allowed. Example of entry through the wall of a house
• If the foundation is piled, everything is simpler: a trench is pulled to the entry point, a hole is made in the floor through which the supply line is inserted. Pile or columnar foundation- simply drag the route to the input point
• If the foundation is shallow, you can run a route underneath it. Lay a metal pipe under the foundation and pass the cable through it. The distance between the cable and the lower edge of the foundation in this case is 50 cm. Less is not possible due to possible ground movements or “subsidence” of the structure.

Laying cables in the ground requires attention. It is very important not to damage the insulation during work, otherwise you will have to redo everything all over again.

Which cable can I use?

To lay cables in the ground, you need to use products with high degree protection from moisture, in a hard shell. Vinyl and polyethylene shells satisfy these conditions.

These are the cables that are usually used: VVB (armored), VVBbG (armor + waterproofing), VBBShv (armor + polyethylene hose). But they are expensive, although they last a long time. It is advisable to use them to supply electricity from the pole to the house.

These types of cable are not suitable for underground installation, but they are still used

When choosing the type of armor, you need to pay attention to the acidity of the soil, the amount large stones, construction waste. For neutral soils with small inclusions of stones, steel armor is suitable.

It is also suitable for clays and loams. For acidic or alkaline soils, lead or aluminum armor is needed. The same cables are best used on soils with normal acidity but with a large number of stones.

Wiring around the site can be done using cheaper conductors. NYM and SIP feel normal. They can work up to 5 years. VVG is definitely not worth using for underground installation. It lasts for a maximum of a couple of years, which, given the volume of land work, is not at all pleasing.

In general, it is wiser to lay more expensive cables, but with a better protective shell. It may cost more at the installation stage, but there will be no problems and you won’t have to think about replacing it with a new one in a couple of years.

Everyone who has ever thought of improving their country plot was worried about the pressing question: how to make wiring in the garden so that it leads to various sockets and light bulbs in gazebos, to lighting lanterns? I also had the opportunity to deal with this difficult matter.

I warn you right away that I am an electrician by profession, so I did everything myself; if someone does not have special knowledge, you cannot start “fiddling” with wiring and electricity yourself. In the best case, nothing may simply work; on average, all the connected equipment will break, and in the worst case, you can harm yourself or one of the crazy people who agreed to deal with the “homemade” electrification of the garden. Electrification of the site should only be carried out by a specialist, no matter how simple it may seem. But at least in general terms it won’t hurt anyone to know how to do wiring, if only to check the quality of work of the same electrician - they are also different. So, the topic of this article is how to install wiring in the garden.

How to make wiring: materials and tools

To install garden electrical wiring you need standard set tool:

• drill with a set of drills
• Screwdriver Set
• good nippers
• pliers
• sharp knife
• hammer
• voltage indicator
• protective gloves

This is the minimum necessary list, without which work can not begin. If the wiring is underground (more on this below), then you can’t do without a good shovel.

Selecting wiring type and installation methods

Garden wiring can be external or hidden. The first can also be temporary and stationary, the second is most often buried in the ground. Here the choice depends on capabilities and needs. Temporary wiring is suitable for those who rarely need electricity in the garden - it is the cheapest, but also the least beautiful and safe. Such a system simply unwinds from the house and rewinds when necessary - no hassles. Fixed external wiring is installed for permanent use and is led to electrification points along poles, trees and external walls of buildings, and is stretched on cables.

It will cost a little more (you need better wire), but it is not always possible to do it aesthetically - it all depends on the layout of the garden, the number of connection points and all that.

I'll tell you how to lay wiring underground. This kind of electrification of a site is much more efficient and safer than others, but you will need a special, expensive cable with reinforced insulation. When connecting pieces of cable to each other, electrical tape is no longer suitable - special sealed couplings are needed.

How to install wiring: sequence of work

All completed work can be divided into several stages according to the sequence.

1. Development of a project in which all lamps, switches, sockets, etc. are clearly indicated. This is the most important stage, on the correct implementation of which the success of the entire event depends.

Even if you want to do all the work yourself, the project must be developed or at least approved good specialist. For example, you can order a detailed garden electrification project with precise specifications and detailed instructions and work from it like a good manual.

2. Next, trenches are dug into which, according to the previously developed project, the cable will be laid. Installation is simple, but labor-intensive: the cable is laid in a trench at least sixty centimeters deep on a ten-centimeter sand bed.

The ends of the wires lead out of the ground to the places where the equipment is installed and connected to the main electrical network.

3. Now you can install all the lamps, sockets, etc. All switching fittings must be placed in places completely inaccessible to precipitation, even if the seller swore that it was waterproof - it would still leak and short out someday. We know, we passed.

4. And only after this you need to install protective automation and connect to a permanent power supply. You can dig trenches after you are firmly convinced that everything is working. The cable is covered with sand and covered with bricks, tiles and other materials that protect against mechanical damage.

Job is done.

Selection and placement of sockets, lamps

Depending on the type of wiring, lamps for illuminating an area can be suspended or ground-mounted; they can provide diffused and directional light that will illuminate a small area or the entire building.

To illuminate garden paths, ground-mounted lamps with soft, diffuse shades are most often used, this is exactly how everything is done in my case.

There will be no problems with the choice of lamps, sockets and switches - there are a lot of types, the main thing is to place them safely.

Wiring safety

The two main criteria for safe wiring in the garden are a good cable and qualified specialist working with him.

Many people hope that in the event of a circuit failure, they will be protected by a central circuit breaker, usually located near the meter. I installed an additional APP (automatic power breaker), which works only for the garden network. Why risk all the equipment in the house?

In order to temporarily supply electricity to certain garden objects, it would be wise to use a ready-made kit that simply needs to be plugged into the electrical network. Such kits are also equipped with an automatic transmission unit, and all junction boxes and switches in them are made waterproof.

That's all. The science is simple, but it requires precision in execution and vigilance in work, because harnessed electricity is a blessing, but when it gets off the leash, it almost always ends badly.

When planning the electrification of a summer cottage, house or industrial area, each master acts on the basis of general construction rules, as well as the rules of the PUE and other documents. According to the data indicated, there are many ways to lay a power line, the most common being an overhead line. But it often happens that, for reasons of architecture and aesthetics of the area, installation using the specified method is not advisable, in which case laying the cable in the ground would be the most appropriate. This article discusses the basic rules for carrying out such work, as well as the question of how to lay a cable in the ground, and the stages of the project.

Areas of application of the method

Laying cables in the ground can be used to supply electrical power to any objects. It can be conditionally classified into several categories, depending on the complexity of the work in terms of safety and the voltage level in the wire:

1. To supply electricity to a private home, summer cottage or outbuildings. This simplest option, when an underground cable is used, since subsequently large excavation work is not carried out on a frequent site by strangers, the owner always has the opportunity to accurately determine the location of the wire and prevent its mechanical damage. As a rule, protective and signaling grids and platforms are rarely used in such a system, since the current flowing through these wires has low voltage up to 10 sq;
2. Laying medium power electrical cables to supply industrial facilities and industrial buildings. In this case prerequisite is the development of a project with the calculation of all parameters, starting from the depth of the trench and ending with the calculated load on the main line, for which it is necessary to comply with the provisions of the PES and other standards;
3. Construction of high-voltage lines. Here, work on laying cables underground should only be carried out by qualified personnel with safety certification and permission to operate at high-voltage sites. Most often, these are special organizations that have Technical Supervision licenses and have all the necessary equipment.

To supply electricity to a private house or summer cottage, the voltage of which will not exceed 10 kV, you do not need to involve a specialized organization, but carry out all the work yourself, observing safety regulations at the site. Most often, such a route is used to organize outdoor lighting, laying a cable in the ground along the entire perimeter of the site between poles or masts of lamps.

Which cable to use

The rules for electrical installations list the types of electrical cables that are suitable for laying in the ground. These wires include:

1. VBBShv is a wire that has sufficient protection for the outer winding in the form of a steel tape, the cores are made of copper, and the internal separation between the lines is made of a polyethylene layer;
2. AVBBSHv – this abbreviation means the same as in the first case, but the internal conductors in the cable are aluminum.

Both types of wire have sufficient protection from moisture and mechanical damage, as well as excess pressure during ground movement. There are no exact recommendations in the rules regarding the cross-sectional diameter of the cable; here it is necessary to calculate the load on the conductors and select a product that corresponds to the rated voltage in the network. Most often, the thickness for a copper cable is 10 mm, and for aluminum – 16 mm, but as the power of the route increases and the voltage increases, the cross-sectional diameter must be increased.

Basic rules for laying cables in the ground

Laying cables in the soil is a responsible job that is best left to professionals. As a last resort, when carrying out actions independently, it is necessary to carefully study all the rules and regulations for the design of power installations, as well as the recommendations of specialists:

1. It is necessary to use only specialized materials intended for these purposes, for example, cable and protective channel. It is prohibited to use wires for internal power distribution, as they do not have sufficient thickness of the winding and metal shield;

Important! When laying a cable in a protective channel, plastic or metal pipe, you should not use a corrugated hose, since if exposed to soil after a year, there will be nothing left of the corrugation, its ribs will fall in and damage the wire strands, which will lead to an emergency.

1. The laying of cable lines in the ground must be carried out below the freezing level of the soil, otherwise when the water hardens, the soil will swell and the line will break. If it is not possible to complete this condition, then the pipe in which the conductor is located must be additionally secured with clamps with driven fittings or support pads must be installed that press the line;
2. The laying of power cables with voltages over 10 kV must be carried out to a depth of at least 70 centimeters, with the installation of a warning tape or mesh. This material in case of work on the site and digging a trench, it will report the proximity to the wire, which will prevent its rupture or mechanical damage;
3. Parallel laying of cables is only possible when installing separation structures made of plastic or concrete between the routes. It is not necessary to make such a partition continuous; dotted placement through equal segments is allowed;

1. Often you have to lay wires under the road or the foundation of a building. In this case, the diameter of the sleeve should be 2-3 times larger than the size of the cable. Often this work is carried out without digging a trench or disturbing the road surface, using the puncture or horizontal drilling method. These methods allow you to conduct electricity in a short time and without additional expenses to restore the coating;
2. If laying cables in a trench is carried out in the cold season, then you need to preheat the wires in a warm room or using a transformer. Laying the cable in the channel without preparation is allowed if the temperature environment not lower than -5 degrees. In other cases, the outer shell of the conductor should be made of soft polypropylene or rubber - these materials do not break in the cold and do not lose their flexibility;
3. The connection of cable sections, when located at depth, is carried out with a special coupling, which compresses the two ends and forms a monolithic joint. This area needs additional protection with insulation or plastic heat-shrink tubing;
4. IN special conditions, when serious soil movements are observed, you can additionally use an asbestos-cement pipe with coupling connection, the laying rules do not prohibit this. You can also use ceramic bricks, using it to build a channel inside which the highway will be located, but only a solid block is suitable for this purpose;
5. The distance between the pipeline being laid and the water supply must be at least 1 meter, and from the gas pipeline - from 2 meters.

How to lay a cable underground: algorithm of actions

For correct installation electrical wire into the ground must be acted strictly sequentially, based on the following algorithm:

1. Preparation of a project or scheme for future communication. The drawing marks all buildings, the distance between them and the exact location of the canal;
2. Site marking. To do this, using a tape measure and metal pegs, you need to measure the distance from the buildings to the future trench, based on the diagram;

1. On next stage A trench is being dug to lay the cable in the ground. It can be dug using special equipment or manually yourself, and the cable laying depth must comply with the standard specified in the PUE. It is necessary to remove all large pieces of earth, stones or pieces of metal from the channel, which could subsequently damage the route, and also eliminate uneven soil at the bottom;
2. Next, a base of fine sand is prepared by adding a layer of 5-10 centimeters with intermediate tamping;
3. Then a special purpose wire is laid at the bottom, which has metal reinforcement and protection. Wires laid in one trench should be at a distance of 10 centimeters from each other. If necessary, at intersections with other communications, under the road or buildings, protection is placed on the wires in the form of a pipe made of asbestos-cement or plastic;
4. The cable is “ringed” by a special test device, which determines the integrity of the line by applying high voltage to the ends. Test measurements must be carried out in a special protective suit, with personal protective equipment;
5. The resulting route is covered with fine sand on top of the laid cable, the layer of which must be at least 15 centimeters. This layer must be compacted with a special apparatus or manually;
6. The entire line is re-checked to ensure that the cable is not damaged during compaction. On top of the laid conductor and sand layer along the entire length of the trench, a signal strip or mesh is mounted, which during further maintenance of the line or in the event of an emergency will indicate the proximity to the electrical main. When re-excavating the channel, the layers will be removed gradually down to this tape, then the work is carried out manually so as not to damage the existing cable;

1. The final stage will be backfilling the soil into the canal. Due to the layers of sand, excess soil is formed; it does not need to be removed or used for other purposes, since as moisture reaches the surface of the earth, the soil will shrink and additional filling will be needed;
2. After the cable is finally laid underground at the dacha and the trench is backfilled, the original covering in the form of a lawn or road surface can be restored.

This algorithm is established by the PUE and is universal, applicable to all types of cables, starting from 10 kV and above. But the technology may not be partially followed in the case where the wiring is local in nature, is low-current and is not loaded with high voltage. For example, they do not have a communication cable or access control metal protection, but can be laid in the ground using plastic pipe as a channel and coating protection. Such lines conduct current much lower than 10 kV, and a short circuit will not lead to a major emergency. In addition, if necessary, this wire can be replaced by pulling it out of the channel and laying a new one, without opening the main soil cover.

The main danger to the cable sheath is underground “stray” current. This physical phenomenon, which arises from the operation of grounded electrical devices, such as washing machines, household network or electric trains. Electricity of these devices and units penetrates the soil along the laid conductor and moves randomly through the soil, affecting communications, while the plastic insulation can crack and harden. To avoid such consequences, if it is determined that the land area is saturated with stray currents, you can lay the cable inside a plastic pipe. This will provide additional insulation of the wire from the ground and increase the service life of the line.

Thus, for proper organization power supply of a building or territory by laying a conductor underground, it is necessary to strictly follow the rules for the construction of electrical installations, as well as general building codes. Only under such conditions will the supervisory authority give permission to use the highway, and its operation will be safe and durable.

Video

The question often arises for owners of private households: is it possible to lay power cables underground? Which wire is better to use? What standards should be followed?
The main method of laying power lines to a private house or dacha is overhead or underground. To transfer electricity to the point of consumption, a method such as laying cables in the ground is used. This is an economical option for installing power lines. The advantage of this method is that the wiring is hidden, which does not spoil appearance buildings, the wires do not get caught in the wind, and the wires will not interfere when moving oversized loads. Well, as a bonus, the cable is cooled in the ground, which prevents it from overheating and damage.

Laying wires and cables underground has many benefits. When installing this wiring, it is necessary to comply with the special technological process. The following advantages can be highlighted:

• Cost-effective, the cost of work will not exceed the cost of the materials used. The most acceptable option, in comparison with laying an overhead line, which requires special approval, Additional materials, technique;
• To avoid damage to the cable, a shallow trench is made and no material or other means are required to maintain the line;
• The ability to lay the cable yourself without resorting to the help of installers and without using special equipment in the form of a tower;
• The wiring location is hidden from view, so it does not spoil the appearance of the area;
• This method allows the use of high-voltage electrical cables of various cross-sections, without the use of reinforcements for suspension devices.

Rules that must be followed for laying wires underground

Installation is carried out in compliance with PTEEP and PUE, regardless of the purpose and type of wire used. The following points must be observed:

• The cable is laid at a depth of 70 cm or more. If the power line is short (less than 5 meters) and the cable is protected in the form of a pipe, then laying at a depth of 50 centimeters is allowed;
  
• It is not permissible to lay wiring under the foundation of a building. A minimum of 60 centimeters should be measured from the foundation to install the line. If a wire stretches from one building to another through the foundation, then it must be protected with a steel pipe. Such protection is mandatory since any cable is susceptible to all sorts of harmful influences;
• The distance in the trench between the wires is usually at least 10 centimeters. Based on this, the size of the trench is calculated;
  
• When laying cables, a distance of at least 2 meters from trees on the site should be maintained; a distance of -75 cm from the bushes is required. These rules can be violated if there is additional protection, for example, in the form of a steel pipe;
• From communications such as sewerage, water supply, it is necessary to make a distance of -1 meter or more, from a gas pipeline -2 meters or more;
• If cables intersect in trenches, they should be insulated from each other with an earthen layer of 50 cm or more in size;
• If an underground wiring method is used, then the wire should be armored, specially designed for this purpose. This is necessary to create protection from the influence of physical influences and underground pests;
  
• When laying using a winch that unwinds the drum, it is necessary to equip the mechanism with a limiter. In this case, installation with a snake is possible, then the line will not have tension;
• If it is necessary to connect an electrical wire, metal couplings are used independently. This connection method gives good contact for a long time;
• For extra protection power line use an asbestos-cement pipe or a special brick structure;
  
  
• After laying the wiring, a warning tape is laid on top with a designation and warning about the electrical wiring.
  

Selecting an electrical cable for underground wiring

In underground wiring, types of armored cables are used - VB 6ShV, as well as VB6ShVng, these products have steel protection. This option is resistant to mechanical damage and will prevent rodents from damaging the wiring.
Having such protection, the cable will last long years. The armored cable is laid without a pipeline, but the use of a pipe is recommended to avoid damage to the wiring by government employees. organizations in the process of carrying out work.
The electrical wire for laying in the ground should be selected taking into account the required power of the facility's consumers. For example:

• • The VBShvng 4x6 cable is designed for a power of 11 kW;
  • The VBShvng 4x10 cable is designed for a power of 15 kW;
  • The VBShvng 4x16 cable is designed for a power of 21 kW.

Work order

There is a certain sequence when laying a leash in the ground:

• Designation of the location of the power line;
• Selecting a cable suitable for this type of work;
• Construction of a trench for wiring;
• Laying cables in the ground;
• Arrangement of wire protection with a cushion, then with soil and signaling tape;
• Carrying out verification work on the operation of the line;
• The final stage is digging the trench.

Stages of electrical wiring work

To create underground wiring, you must have special knowledge:

• The first step is to mark the route on the ground for the power line at the dacha, suburban area etc.;
• When marking, it is possible to use all kinds of stakes and ropes. It is necessary to carefully ensure that there is no intersection with communication networks;
• It is worth creating a cable layout plan. The drawing indicates the distances for the cable exiting the ground, as well as its turns. It is important to check before installation whether the wiring is disconnected from the mains voltage;
• Then a trench is dug according to the markings made. As a rule, its depth is 80 cm, the width for laying one cable is 20 cm. The bottom of the dug trench should be compacted;
• There is an option - the bottom of the trench is lined with red brick;
• If you plan to conduct electrical wiring across the road, then in this case the depth should be at least 120 cm;
• When laying the cable in the ground, it is necessary to clear the trench of branches, stones and other objects;
• Next, a cushion of sand -12 cm is poured in. It will protect against the possibility of a wire break;
• The de-energized wire must be placed so that it is not too taut. As a rule, they lay the whole wire without connecting sections;
• The final stage is backfilling the trench with electrical wiring. After this, the cable is checked for short circuits and its armor is grounded.

Be sure to watch the video on how to lay cables in the ground correctly:

IN winter period Underground installation of the electrical wiring line is permissible, the following must be taken into account:

• Before installation, the cable is warmed up in the living room. The heated cable is laid, preventing freezing. If the frost is more than 20 degrees, the possibility of installation is excluded;
• If the air temperature is minus 5 or higher, it is possible not to carry out the warm-up procedure if the wire is high pressure;
• At a temperature of minus 7, it is permissible to lay a conductor protected by insulation;
• If the temperature is minus 15 or higher and the conductor is protected with PVC film or a rubber sheath;
• Laying at minus 20 degrees is possible, if the wire is protected with PVC sheath or rubber insulation and if there is a lead sheath on top.

There are details that are worth considering; they will help to carry out the work more correctly:

These rules for laying underground wiring must be followed for safe work and subsequent operation. If the rules are violated, troubles may arise that will be difficult to correct.

Modern dacha settlements are necessarily electrified. But the necessary communications, as a rule, are laid only to the main building on the site. The owners, settling the site, often need to lay cables to other structures: a gazebo, barn, garage, etc. The safest way to do this is in the ground.

Advantages of underground cable laying

In addition to this method, external one can be carried out by air. At first glance it may seem that it is easier. After all, you don’t need to waste time and effort digging a trench, and the problem can be fixed faster. But in reality it turns out that it is more reliable to properly insulate and lay the cable once, fully observing the technology that is regulated legislative documents. All work can be done with your own hands, and the subtleties of the process are outlined in a thematic video.

Advantages of the underground cable laying method:

1. Any gauge of wire can be used. You will not be limited by its weight and strength of supports.
2. The cost of laying cables is often lower than with the air method.
3. Aesthetically, the wires look more attractive because they are not visible.
4. Complete security. With proper insulation, the cable will lie in the depths of the earth for many years, without forcing you to remember about it.
5. Convenient connection of communications.

Attention! From external devices, it is enough to connect one toggle switch at the line output. With its help, you can completely cut off power to all other buildings in one motion.

Basics of dacha electrical equipment

Energy supply at the dacha consists of the following stages:

1. Bringing switching to the site. The connection point on the pole is a power panel with a meter for metering consumed electricity. It can be located at the top or bottom. As a rule, your dacha is already powered: the cable is laid from the pole to the power panel of the house. But sometimes you have to do it yourself, also underground.
2. Laying cables to power consumption points on your site. This is exactly the stage where you need to dig trenches. Place the cable in them, but don't bury them yet.
3. Functionality check. If your internal network is extensive, it is better to involve energy specialists for testing. Additionally, you will need to check the line insulation resistance and network phasing.
4. Final work: digging trenches, connecting equipment.

Not every cable and not every insulation is ready to go underground. Buy only certified, high-quality products suitable for this installation method. The best option— power cable series VVG. In any case, the cross-section should not be less than 4 mm.

Advice. The VBBSH cable copes well in such conditions. This special material for underground work. It does not require additional insulation with a pipe, since it is already built into the steel sleeve.

Features of underground cable laying technology

Even before purchasing a quality cable, you should calculate the required length. To correctly position it on the site, draw up a trench plan. It is a mistake to assume that it is most effective to dig along the shortest path to energy consumption points. This procedure has several nuances:

• the cable should not be located closer than 1-1.5 m from large trees (roots will interfere);
• you can't draw a line along garden beds, front garden and other places where digging or construction work is possible in the future;
• correlate the trench network and the location of other underground communications on the site;
• It is not recommended to pave the way under a car parking lot and other places with increased pressure on the soil;
• It is most reliable to place the network under garden paths and next to them;
• minimum location from the foundation of the house is 60 cm.

Attention! The last requirement is difficult to fulfill, for example, when laying from a residential building to a bathhouse or other nearby building. In this case, protect the line with steel pipe.

Experts advise first powering all required buildings. After this, make the wiring for outdoor lighting, if you plan to do so. It is generally better to carry out these works at different times. They require thoroughness, as well as time for planning and experimentation.

How to lay cable on site

The process of creating an underground network on a site consists of the following steps:

1. Mark the area and dig trenches according to your design. Optimal sizes for them: from 80 cm in depth and 20-30 cm in width. For laying the external lighting cable, the depth can be one third less.
2. Remove debris, rocks and any other sharp objects from the trench that could damage the wire insulation.
3. Place a sand cushion about 10 cm thick. The material should be distributed evenly along the entire length of the trench.

After preparing the trenches, it’s time to start laying the cable. The purchased wire, no matter how durable and waterproof it may be, must be hidden in a pipe. Technically the best solution in this situation there will be HDPE pipes. They are precisely designed for such communications.

There is no need to buy material that meets GOST. It is designed to be transported drinking water, and therefore quite expensive. Exit - technical pipe from recycled materials. It is many times cheaper and no worse for electrical wiring.

Attention! The pipe must be even, smooth and round: both inside and outside.

Photo instructions and recommendations from electricians will help you when laying the cable:

• Try to use whole pieces of pipe. They can be connected with fittings. But be prepared that the seal will probably suffer as a result.
• The cable must also be intact. Check this very carefully before inserting into the pipe. No connections are allowed!
• The wire should be placed freely in the pipe, without tension.
• The line should be placed evenly in the trench, without protruding above the ground level.
• Before burying, it will be useful to cover the wire with a layer of sand (5-10 cm).
• Warning tape is useful for safety. In such work, a sand layer is laid with it exactly along the cable line.
• The trench is buried with ordinary soil. Definitely with a mound, because the earth will subside over time.

Like any construction work When laying cables in the ground, a diagram and a clear work plan are important. Use only quality materials. If these conditions are met, you will be able to operate the electrical system on your summer cottage many years.

Laying electrical cables underground: video