How to lay the cable in the courtyard of the house

Wiring methods, practical experience and the price of the issue.

In the practice of housekeeping, it is often necessary to connect some devices or structures located near the house. Electricians call this process branching. For example, it can be a garage, a trading stall, a street lamp or just a canopy with lighting (a gazebo in the garden).

Let's try to consider various ways of creating a branch or in an understandable language laying an additional power cable. According to established practice, the power line from which the branch will be made is most often air. In some cases, an underground branch is used.

Air lines

Air lines in most cases are more reliable, because their damage can be detected visually and, if so, they are restored much faster than underground ones. Just imagine how much time, labor and money you need to spend to find and restore the “broken” power cable under snow in frozen ground ?! But, of course, both the overhead and underground power lines have both their advantages and disadvantages. Otherwise, electricians all over the world have long stopped at one option.

Legal subtleties

Always try to do everything so that you have everything and you have nothing for it. When it comes to electricity, we affect the interests of one of the monopolists of our country. According to existing standards, both air and underground branches are considered part of the baseline. The owner of the mains maintains and is responsible for the execution and condition of the branch.

In order for all the work to be accepted without comment, invite the representative of the owner of the network in advance and familiarize him with your project. Even better if you conclude an agreement with him for the creation and subsequent maintenance of the branch. Remember that "Avaricious pays twice."

Do it yourself

If you started the work yourself, you need to know what materials you need to apply and what rules to follow. The best way to create an air branch is SIP self-supporting aluminum insulated wires. These cables are very durable (service life more than 25 years), they have special accessories for easy and convenient mounting to poles and buildings. Such cables have a different number of wires for single-phase and three-phase networks.

These are cables of types SIP-2A, SIP-3, SIP-4. The cable cross-section must be at least 16 square millimeters, i.e. it can pass current up to 63 A, which corresponds to a power of 14 kW with a single-phase network and 42 kW with a three-phase. SIP - uses an aluminum wire, and cables made of aluminum can not be led through the attic.

Usually used there VVG NG or NYM section from 10 square millimeters, if you need maximum load power. For the transition SIP - VVG NG need to use hermetic connectors aluminum - copper. SIP are mounted on special anchor clamps - tensioners. Entering the wall is made through a metal sleeve. If we talk about costs, then the cheapest SIP-4 2x16 costs from 23 rubles. per linear meter.

Lengths and heights

For overhead lines, there are additional rules for lengths and heights.

1. If the distance to the object is more than 25 meters, you need to put an intermediate support.

2. When passing over the carriageway, the cable height should not be less than 6 meters.

3. Above the footpath, the height should be more than 3.5 meters.

4. When connecting to the building, the wires are fixed so that their height from the ground is more than 2.75 meters.

Underground branch

If you do not like the “ropes” hanging above your head and the icicles falling from them in the winter, then your path is an underground cable.Speaking of an underground branch, they usually do not mean a clutch lying in the ground, to which one cable approaches, but two depart. The coupling is an extreme case and only for repair work. Usually you have to dig more than once in the place of the coupling ... The transition to the underground branch can be from the overhead line or from the shield in the building.

Materials, prices, rules

For underground branching, it is best to use armored cables of the VBBSHV type with copper conductors with a cross section of 10 square millimeters. Such a 4x10 cable costs from 200 rubles. per linear meter. It can be put directly into the trench without protective pipes. You can reduce costs and use a conventional cable, such as VVG NG.

This cable with a cross section of 4x10 costs from 150 rubles. This cable runs into plastic HDPE pipe. Since it is impossible to drag a large piece of cable straight away, threaded sleeves for plastic pipes are used. The price of a plastic pipe with a diameter of 32 mm from 22 rubles. per linear meter. Metal pipes should be used if a cable runs down to and from the ground along a wall or pole. In this case, use a pipe or corner with a height of at least 1,8 meters.

Also, metal or asbestos-cement pipes are preferably used as a jumper when passing the cable under the road. Until the land above the recently buried trench is compacted, heavy vehicles can push it up to the cable.

A cable trench with a depth of not less than 0.7 meters is used for laying the cable, sand with a layer of 10 cm is poured on its bottom, and the cable is also covered with a layer of sand on top. This is done for uniform soil pressure on the laid cable. Entering into the building is done through a steel sleeve or in a steel pipe under the foundation. This protects the cable from damage during shrinkage and movement of the wall or foundation.

Issue price

If we talk about the cost of the branch and what is cheaper "earth method" or "air", then it is difficult to give a definite answer. With the air method, there are no earthworks, but the posts are expensive, their installation and the work of electricians from the aerial platform to fix and connect the cable. If you need several poles for laying the cable, then it will be cheaper to dig a trench if it is not rocky soil, if ... etc.

Life teaches us that any business must first be done mentally, make a decision and not back down until you have completed it. Count both options, then count your money, think, maybe you don't need it? But if you’ve got it fast, act and don’t hesitate anymore until you’ve finished.

How is trenchless pipe laying performed

During pipe laying, complexity arises when obstacles arise along the way. Artificial barriers do not allow to dig trenches. There is an exit. When soil cannot be destroyed, trenchless pipe laying is used.

Motorways and railways can be bypassed. Before starting trenchless pipe laying in the ground, the soil is examined, the state in which the groundwater is located is analyzed. We pay attention to how far the pipeline will be removed from all obstacles, external factors.

It is also worth deciding on the laying parameters, the size of the pipes. Experts study the situation, and then decide which method is suitable.

Trenchless pipe laying can be carried out in several proven ways. The best option is to lay the pipe through a puncture. This operation does not harm the soil, as required.

Pipe Stacking Puncture

If the pipe is selected no more than 600 mm, then it can be laid with a puncture. The soil should be either clay or loamy. A paved run usually has a length of 60 meters. To perform a puncture, few hand tools and the pipe itself, you need special equipment.

Tools and equipment for the task: bulldozer, tractor, winch, hydraulic jack.  

When a puncture is carried out, installation work can be carried out under rails, buildings, highways, as well as protected areas.

If you need trenchless laying of pipes in a summer cottage at a minimum distance, then a puncture can also be issued. The master must have good physical strength and equipment. This number includes a sledgehammer, fittings, the diameter of which is not thinner than 20 mm, a welding machine, several parts of a steel pipe, and a grinder.

Stages of a puncture in a personal plot

We dig an obstacle, or, for example, a road, from two sides. Pits are made in the size of pipes with a small margin of several centimeters. We mark where the axis of the pipe will be. With a grinder, we cut the teeth on a piece of pipe to make it sharp.

Drive the end into the ground with a sledgehammer. With each advance into the ground, it is worth taking out and washing out the soil from the pipe. We do the work until the pipe comes out on the other side.

In general, a puncture is not difficult to perform. It is profitable and convenient if it is impossible to lay pipes differently.