How to make grounding in a cottage. Do-it-yourself grounding at home. How to do. Triangle - closed loop

Modern household and computer equipment cannot function normally without protective grounding. In its absence, under certain conditions, the electronics will simply fail. This is especially true for suburban areas and rural areas, where old equipment and power lines are still in use. Many of them are in poor condition and do not provide the required level of electrical safety. Therefore, the owners living in such places are forced to independently make protective grounding in a private house or in the country, since it is not always possible to attract qualified specialists for these works.

If everything is done correctly, including, then in the event of current leaks, the residual current device is triggered instantly - the RCD and the dangerous area is de-energized. Exactly the same events are held in a wooden house.

The need for grounding in private homes

Among the measures to ensure the electrical safety of suburban households, the most important component is protective grounding in a private house, filled with a large number of modern household appliances. In addition, the home electrical network scheme will not be approved and approved if it does not have a protective earthing system.

Proper grounding allows you to effectively solve the following tasks:

Protection against electric shock to people living in the house, in case of contact with devices that have broken insulation. If necessary, even grounding of the electrical panel is performed.
Ensuring the correct and safe operation of modern equipment and household electrical appliances.
Gas equipment () will be operated in a safe environment.
Significantly increased efficiency, grounded and connected into a single whole with the entire system.

The organization of grounding and its necessity are based on physical laws that determine the movement of electric current to the side with minimal resistance. When the insulation of the device is damaged, it goes outside and closes on the case. The equipment ceases to function normally, and a person risks being electrocuted if he accidentally touches such a surface.

If grounding in a private house is installed and mounted in accordance with all the rules, the distribution of electric current will occur taking into account the resistance of the human body and the ground loop. Since the grounding resistance is significantly lower compared to the body, the current will begin to flow along this particular circuit and go into the ground without causing any harm to a person. This is the simplest answer to the question.

The principle of operation of grounding systems

The main function of any grounding system is to connect electrically conductive parts of devices and equipment with a special metal structure that is in close contact with the ground. In electrical engineering, this design is known as a ground electrode, or grounding device. It consists of metal parts made of corners, pipes, and other profile materials, connected to each other by welding.

Protective grounding devices reduce the potential at the point of contact of a person with the body of the device and bring it to a safe level. This is the principle of operation of these systems, based on the movement of electric current in the direction of minimum resistance. The whole process takes a very short time, during which the protective automatic device is triggered - the RCD, which completely cuts off the voltage supply.

Modern standards provide for the use of a three-core wire in the internal electrical network. Among the three cores there is a conductor, with the help of which the socket is grounded in a private house and the subsequent connection of devices and devices with a pinching circuit located in the ground. When used together with lightning rods, protective systems are additionally equipped with arresters capable of withstanding high currents and voltages.

The main requirement for the grounding structure of the cottage is the introduction of metal parts into the ground. The improvement of such contact is facilitated by an increase in the electrical conductivity of the soil near the ground electrode, carried out in various ways. One of them is the direct chemical impact on the soil with various reagents, including salt. This factor must be taken into account when grounding a private house with your own hands. If the design is done correctly, the current will flow freely into the soil.

Types of grounding for a private house

When erecting a new building or replacing old wiring, the owners have to solve the problem of which grounding in a private house to choose in a particular case. For modern facilities, TT and TN-C-S systems are most suitable. Each of them has its own characteristics, as well as positive and negative sides. Considering them will help you figure out which grounding to choose.

It should be taken into account the factor that transformer substations and power lines with four wires are used to supply power. This is especially important when doing grounding in a private house with your own hands at 380 volts using three phase and one PEN conductor that combines ground and zero.

If the TN-C-S private house grounding scheme is used, then the input is equipped with a re-grounding of the PEN conductor. If the TN system is used, in this case this combined conductor is divided into PE and N. In this case, three- or five-core wiring is already used. The interconnection of PE and PEN conductors is strictly prohibited. In this regard, the point of their separation must be in front of the switching devices.

A serious disadvantage of such systems is the occurrence of dangerous voltage on the housings of electrical appliances in the event of a break in the PEN conductor. Therefore, this scheme is used only on modern power lines equipped with a low probability of breakage.

In TT systems, there is no connection between the building ground and the PEN conductor. This is what distinguishes this ground loop in a private house from the previous scheme. The main disadvantage of such a system is the appearance of a dangerous potential on the device case in the event of a phase-to-ground short circuit. To operate the machine, the short circuit current is not enough, therefore, RCDs are additionally connected to ensure a guaranteed power outage. Such a scheme is suitable not only for a private house, but also for a summer cottage.

Grounding in private houses with old wiring

Many owners of cottages and private houses are faced with the problem of connecting individual grounding in the presence of old wiring diagrams, often in a dilapidated and even out of order condition. In such cases, the most acceptable option is to completely replace the home network, when the entire wire and cable is changed.

This option is considered expensive and not everyone has the financial means to implement it. Therefore, it is necessary to use existing resources and solve the problem by improving and improving them.

It is recommended to start repairs with the installation of new junction boxes, sockets and switches. The places of their installation and the input itself can be left the same, paying only attention to the presence or absence of ground wires. Before connecting the ground, they are connected through the junction box to the ground bus installed in the shield.

Otherwise, you can completely turn off the old network and leave it inside the wall. Instead, external wiring is laid in plastic cable channels. To install new sockets and switches, you can use old holes or drill new ones in more convenient places. Distribution boxes must also be freed from old wiring.

If desired, the old wire can not be disconnected, but used to connect low-power household appliances. A new line equipped with earthing will require the installation of a more modern switchboard. If there is no desire to change all the wiring, the ground connection can be made only by laying a ground wire laid in a plastic cable channel.

The main components of grounding for a private house

Before proceeding with the grounding device, you need to study all the details and elements that are required for grounding in a private house and determine the places for their installation and installation.

First of all, a ground loop is equipped, which is a prefabricated structure. For its manufacture, smooth bars, steel pipes, corners and other typical profile materials, as well as a ground wire are used. After being placed in the ground, the individual parts are welded together, providing high-quality contact with the ground and rapid flow of electric current into it. In conjunction with the ground loop, an RCD is usually installed, which instantly turns off the network in case of contact with live parts.

In addition, with the grounding device, you will need to do the following:

On the main grounding bus - GZSH, installed inside the shield, a separate PE terminal is created, which will be used to connect the re-grounding.
A copper wire is drawn from the same terminal, intended for connection to the ground electrode.
Next, the manufacture of the grounding structure itself, which is installed in close proximity to the house, is carried out.

Grounding conductors are artificial, created on purpose, in the absence of existing conditions, and natural, when existing building structures, parts and elements suitable for these purposes are used.

If you plan to do-it-yourself grounding in the country, the scheme in this case is recommended using natural elements. Metal or reinforced concrete elements of the building itself are best suited. You can use steel pipelines, lead protection of the power cable and other metal structures in the form of supports and poles.

Ground loop design

Since the ground loop is the main element of the system, its design should be considered in more detail.

As a configuration, a triangle, rectangle, straight line, arc or oval is used. Most often, a grounding device in a private house is made with a triangle-shaped circuit, since this is the most optimal option, which is best suited. Its isosceles configuration contributes to the creation of the largest current dissipation area. The design parameters meet all standards, and the cost of arrangement is minimal.

The distance between the individual pins can be from one to twice the length of such a pin. That is, when driving an element 3 meters into the ground, the distance between them will be from 3 to 6 meters. Such indicators provide normal ground loop resistance. The sides of a triangle are not always straight. It is allowed to shift the pins in the presence of stones and other obstacles inside the ground.

Often, natural conditions allow you to use only a semicircular or in-line circuit for connecting, when the pins line up. Such a scheme involves the use of a larger number of electrodes that provide a sufficient current dissipation area. This is a serious disadvantage due to the increase in the material consumption of the structure and problems when driving into the ground. Therefore, if possible, the owners of any country house try to make a contour in the form of a triangle.

For maximum grounding efficiency, loop resistance should not exceed 4 ohms. This condition ensures high-quality and reliable connection and contact of ground electrodes with the ground. Much also depends on the materials used as a connecting agent for the pins. Usually, a steel strip or a corner is used for these purposes, connected to the electrodes by welding.

Pay special attention to the quality of the welds. For a bundle, as a conductor, you can also use a copper wire with a cross section of at least 10 mm 2, or aluminum - with a cross section of at least 16 mm 2. Large bolts welded to the pins are used as fasteners. The wire is wound onto the bolt, pressed with a washer and fixed with a nut.

Installation of a ground loop in a private house

After studying theoretical issues, including why grounding is needed in the house, you can proceed to the direct installation of the circuit.

The procedure for grounding a residential building begins with the choice of installation site. This site should be free from any communications, therefore, all necessary approvals with the relevant services must first be completed. Next, one of the ground loop configurations discussed earlier is selected. After that, you can begin to install the electrodes yourself without helpers.

To facilitate this procedure, it is recommended to use a hand drill. With the help of a drill, the first hole is made in the ground to a depth of about 2 meters, after which the first pin is driven in. If it easily enters the ground, then all subsequent electrodes can be driven deeper, but not more than 3 meters. In this case, the pin will simply get stuck and will not go any further.

Upon completion of driving, all ground electrodes are cut off in the upper part 15-20 cm down from the ground level. Between them, a groove is dug to the same depth for laying the connecting elements. Then all parts are connected by bolts or welding. A special ground wire is connected to the closest part of the house. The disadvantage of bolted connections is the need to periodically check them, tighten the contacts and clean them from rust.

When solving the problem of how to properly make grounding, it should be borne in mind that its operation is based on elementary physical laws. Their exact observance at all stages of the system design guarantees its further stable and efficient operation. Its effect will be the higher, the larger the area of contact between the contour and the ground.

In this regard, the owners of such objects are advised to observe the following rules:

The grounding system in a private house cannot do with a single metal pin. Even if you drive it too deep, it will not create a full-fledged contour. In some cases, the solution of the problem of how to make grounding in a private house becomes possible only with several ground electrodes using at least two triangular circuits located at a depth of up to 3 meters.
It is impossible to ground the house using parts with a high surface density for the contour. These include profile fittings, rails, channels, etc. A circuit made of these materials has very poor contact with the ground, and sometimes there is no contact at all.
When choosing the number of circuits and calculating their total area, one should proceed from the total power of the appliances installed in the house. The more such devices, the larger the entire grounding of a private house should be.
To protect the metal parts of the circuit from corrosion, they must be coated with a special protective coating that conducts electric current before being placed in the ground. It is forbidden to use ordinary paints and varnishes for this purpose.

Content:

Many people live and spend time in dachas and private country houses. They try to create for themselves maximum coziness and comfort, to surround them with all modern conveniences. The vast majority of such objects are fully electrified, so the question often arises of how to make grounding in a private house with your own hands.

Do-it-yourself grounding scheme in a private house 220 and 380v

In each private house, grounding is arranged depending on what voltage is connected to it - 220 or 380 volts. Both grounding schemes practically do not differ from each other. In both cases, the ground loop device will be exactly the same. The existing differences relate to the connection method, depending on the type of electrical network.

When connected to a single-phase network, with a voltage of 220 volts, three wires are used - phase, zero and ground. The sockets also have three corresponding pins. If a three-phase voltage of 380 volts is connected, five wires are already used, of which three are phase, and the other two perform the functions of zero and ground. The sockets also have five pins.

It is strictly forbidden to use a neutral wire instead of a grounding conductor, regardless of the voltage in the electrical network. In this case, the failure of expensive household appliances and equipment is quite possible. In addition, a real threat to the health and life of people in the house is created.

When installing grounding in a private house, the difference in resistance should be taken into account. If the installation is carried out in accordance with all the rules, then the grounding resistance with a voltage of 220 volts will be about 30 ohms. At a voltage of 380 volts, this figure will be equal to 10 ohms. An important role is played by the resistivity of the soil in which the ground loop is laid. For example, rocky soil has very low rates.

Grounding schemes

First of all, you need to decide on the most suitable variant of the grounding scheme for a private house. Depending on this, the entire system will be mounted in the future.

The most popular grounding schemes are:

A closed circuit in the form of a triangle. Its main advantage is more reliable operation. In case of damage to the jumper between the pins, the operation of the system will continue from any whole side.
The linear circuit consists of several pins dug in on the same line, connected in series with each other. The disadvantage of such a system is its complete failure if the jumper installed at the very beginning is damaged.

For private houses, a triangle is best suited. In terms of the amount of work, this scheme is no different from other systems, but its efficiency is much higher. Based on specific conditions, you can use your own option and perform a grounding configuration in the form of a rectangle or other shapes.

Necessary tools and materials

For the manufacture of artificial ground electrodes, rolled steel is used. Round bars, pipes of different sections and corners are best suited for these purposes.

It is strictly forbidden to use profile fittings as grounding conductors and grounding conductors. This is due to the hardened outer layer found in all products of this type. As a result, the current distribution over the cross section is disturbed, and the oxidation process occurs much faster.

In order to protect the metal from corrosion, the use of galvanized electrodes is practiced. In some cases, electrically conductive concrete can perform the functions of a grounding conductor.

There are prefabricated kits consisting of seamless copper-plated pins. Their length is 1.5 meters, and there is a thread at the end. To connect the pins to each other, special brass threaded couplings are provided. Immersion in the ground of the electrodes is carried out by high-power hand impact tools with the help of an adapter and a guide head. The electrodes are connected to the ground conductor with clamps made of stainless steel. Corrosion protection at the joints is carried out by coating with a special paste.

Ground electrodes must not be painted or coated with other coatings that reduce conductivity. However, under the action of corrosion, the thickness of steel parts gradually decreases. This factor must be taken into account, so the electrode cross section is selected with a certain margin. Thus, a sufficiently long operation of the circuit is ensured.

The regulatory documents define the minimum allowable cross-section of ground electrodes, which should be taken into account when choosing materials. So, for a galvanized rod, this parameter is 6 mm2, for a rod made of ordinary ferrous metal - 10 mm2, and for rectangular rolled products - 48 mm2. Pipe walls or rolled steel flanges are selected with a minimum thickness of 4 mm.

Of great importance is the correct choice of material used to connect the electrodes. In most cases, a strip is used, however, in certain conditions, the use of a pipe, angle or wire is allowed. With these materials, grounding can be brought directly to the electrical panel. The cross section of the grounding conductor located inside the building must match the cross section of the phase wire used in the wiring.

All ground conductors are connected to a single ground bus used for switching. The tire itself is made of special electrotechnical bronze. It is one of the elements of the switchboard and is fixed directly on its wall. A sledgehammer and a ladder may be required to complete the work. The connection of parts from rolled ferrous metal is carried out by welding.

Installation of the grounding system

In private houses, use is practiced in the form of a triangle with equal sides. In order to make a ground loop in a private house with your own hands, the markings for the future design are performed in exactly the same configuration. The grounding distance from the foundation of the building should not exceed 1 meter.

After marking, a trench is cut off along the entire perimeter of the triangle to a depth of 0.8 to 1 meter. Its width is from 50 to 70 cm, which ensures the convenience of welding and other work. The trench itself is necessary for laying horizontal connecting ground electrodes.

At each vertex of the triangle, vertical ground electrodes are driven from a corner 2-3 meters long. They are buried almost completely with sledgehammer blows. To better enter the corners into the ground, their ends are pointed. The device of small wells opposite each vertex of the triangle, about 1.5 m deep, will help facilitate the work. In this case, the corners are hammered into the ground at a shorter distance.

After completing all the preparatory work, you can begin the direct installation of the ground loop:

At the very beginning of work, the corners are driven into the ground so that their upper edge protrudes above the bottom of the trench by about 20-25 cm.
Upon completion of the installation of vertical grounding, horizontal piping is performed in order to create a closed loop. All connections are made by welding - a steel strip is welded to the ends of the corners. The use of bolted connections is not allowed, since after a while oxidation of these places occurs. As a result, the contact is lost and the ground loop starts to work inefficiently.
After complete assembly of the ground loop, it must be connected to the electrical panel. This is done using a grounding conductor, for which a steel wire with a cross section of 8-10 mm is used. It is welded to the contour and then laid in a trench to the junction with the shield. A bolt with a diameter of 6 or 8 mm is also welded in this place, to which the ground wire will be attached.
If there is no steel wire, then a steel strip, the same as in a horizontal ground electrode, may well become a grounding conductor. The strip will be even more efficient because it has a larger area of contact with the ground. However, it is harder to work with, especially when laying on the bends of the trench.
Upon completion of all welding work, the welding points are treated with special anti-corrosion compounds. Paint cannot be used for these purposes, since it completely breaks the connection between the metal and the ground and the grounding system simply will not work.

After checking all connections, the excavated trench is covered with earth. Next, grounding must be connected to the equipment installed in the house. Many private houses use the TN-C grounding system, where it is grounded. After installing your own ground loop, such a circuit will no longer work and will require alteration to a TN-C-S or TT system.

Earth connection system TN-C-S

The TN-C circuit does not have a separate ground conductor, so it needs to be converted to a TN-C-S circuit. To do this, it is necessary to divide the combined PEN wire in the electrical panel, which is both a zero working and protective conductor. After separation, two separate wires should be obtained: N - working and PE - protective.

Since only two supply wires are connected to the house, in order to obtain a three-core internal wiring, it is necessary to use a special PE ground bus connected to the shield through a metal surface. The PEN wire connected from the outside network is connected to it.

Then the PE bus is connected by a jumper to the same bus connected to the zero working conductor N. The zero bus is necessarily isolated from the shield. After that, the shield itself is connected to the ground loop. For this purpose, a stranded copper wire is used, one end of which is connected to the shield, and the other is attached to the ground conductor using a bolt welded on the end.

Grounding connection according to the TT scheme

This system does not require PEN conductor separations. The scheme provides for the connection of a phase conductor to a bus isolated from the electrical panel. Further, it will serve as a neutral wire. After that, the shield body is connected to the ground loop.

Thus, do-it-yourself grounding in a private house according to the TT scheme does not provide for any electrical connection of the circuit with the PEN conductor. This connection has significant advantages over the TN-C-S scheme. When the PEN wire burns out, the zero potential on the instrument cases will remain. Therefore, the CT circuit is considered more reliable and safer. Its high cost is considered a serious drawback, since the presence of protective devices is mandatory in the circuit.

How to make the grounding of your home yourself

For a grounding device in a country house or in the country, you will need a little patience, building materials, a minimum of tools, and a little knowledge gained from this article. We will not think about what kind of grounding is and what grounding options should not be adopted. Also, let's not bother with information about the equivalent soil resistivity and the values of the calculated climatic coefficients of soil resistance seasonality.

We will go exclusively in the best way - we will take the successful experience of the already completed installation of grounding, which was carried out on the basis of an approved project, it was checked and the competent services gave the appropriate operating permit.

First, let's roughly calculate what we need:

Tool

Welding machine and mask for welding.
Sledgehammer 5-8 kg.
Shovel (bayonet and shovel).

materials

Steel corner 50 x 50 x 4 mm X 3 m - 3 pcs.
Steel corner 50 x 50 x 4 mm X 1.5 m - 3 pcs.
Steel rod D - 14 mm - length - from the place of installation of the ground loop to the house + height to the gable + a separate bar from the ground loop to the house and up to the ridge (when installing lightning protection).
Electrodes 3 mm.
Wire 4 x 4 mm 2 - length, from soldering with a rod, to the shield.
Corrugated pipe for cable - length, from desoldering with a rod, to a shield.
Terminal for connecting rod and wire.

Laying the outer part of the ground

Let's start with what we got. This is a country house in the village, that is, the requirements for electricity and security are at a high level.

Pole wires powering the house.
Rod 14 mm. It comes out of the ground and rises to the place of desoldering and lightning protection.
The place of desoldering (connecting) grounding, and power wires from the pole.
cable 4 x 4 mm in a corrugated pipe going to the shield in the house (3 phases, zero with earth in one core)

Wires from the pole to the house.

2 rods welded to the ground loop and coming out of the ground. 1 for shield, 2 for lightning protection.

Corrugated wire - ground with zero and 3 phases entering the house.
Wooden pads for cables and grounding rods - to avoid direct contact with the house.

Lightning protection, arranged on the ridge of the house.

The arrow shows a grounding rod that comes out of the ground and rises to the ridge to be connected to the lightning protection cable. For the lightning protection device, a steel cable was used, with a diameter of 8 mm, the tension between the supports is achieved due to the door spring.

Location for wiring. 1 - 3 phases; 2 - zero connected to the ground.

This is the same place of desoldering from a closer angle.

Wire 4 x 4 mm. In the corrugation, coming from the street into the house, on the electrical panel.

Electrical shield. Separately, we see an earthen vein that is in contact with the shield due to the standard bolted connection located on the shield door.

And now what we have left behind the scenes, that is, underground.

Where we decided to bury the ground loop, we tear off a moat in the form of an equilateral triangle - external dimensions 1.8 x 1.8 x 1.8 m, width - 40-50 cm, depth 1 m.

Accurately marking three points, between which the distance of 1.5 meters we hammer in the electrodes - 3 steel, 3-meter corners. This is where you really have to work hard. Corners on one side can be sharpened with a grinder - for better entry into the ground. Corners must be hammered strictly vertically. It will be necessary to drown them at half the height of the moat, that is, half a meter from the ground level, it will turn out deeper - please, it will only be inconvenient to carry out welding work.

We carefully weld three one and a half meter corners to the electrodes hammered into the ground - the corners, we weld all adjacent planes well.

Then, you need to measure the resistance of our grounding. For reference, the maximum allowable resistance for a single-phase wiring system is 30 ohms. Special, competent services in this matter hammer 2 electrodes into the ground and check with their device. For us, in order to be sure that the contact of our circuit with the ground is good and the resistance does not exceed the permissible parameters, that is, our work is not in vain and the grounding device with our own hands in your private house will be really reliable, you need to do the following:

Find the socket closest to the buried steel structure in the house and use the indicator to determine the phase.

Ground resistance test

Then take a lamp with a cartridge and power one of the lamp contacts from the phase in the socket, and connect the second to the ground loop. If the lamp burns brightly, then the connection with the ground is good and the resistance does not exceed the permissible values. If the lamp burns dimly or does not light at all, then the resistance exceeds the permissible values, such grounding will not protect the house. It will be necessary to increase the area of the ground loop and check again.

If the test is successful - the lamp burns brightly, the resistance is acceptable, then we weld one end of a metal 14 mm rod to the steel corner of the ground loop and lay it to the house in the ground. Then we lift it under the pediment and commute with at least 4 copper squares from the core and lay it in the shield. In the shield, we connect the earth to the body of the shield using a standard, bolted connection and distribute the earth among household appliances and sockets. We return the excavated soil to the ditch.

A lightning protection device, when the ground loop is ready, will take a little time and save you from possible troubles.

Typical grounding device error

In this video, the grounding device is made, say, with a C grade with a plus. Reinforcement or corrugated metal is not used as electrodes or metal driven into the ground, since by its properties it is not able to stay in an aggressive environment for a long time - this leads to its inevitable rapid corrosion, respectively, such grounding will fail quickly enough. When using a rod, only a smooth surface is justified. And the method of hammering metal into the ground with the help of a perforator, frankly, pleased me, for this respect to the author.

More recently, protective grounding was equipped only at industrial enterprises and other facilities where powerful electrical installations are used. To protect their employees from accidental breakdown to the case, each installation and device was grounded without fail. But time does not stand still. Today, our homes are crammed with powerful household appliances: refrigerators, freezers, microwave ovens, induction cookers, underfloor heating systems and much more. But all this is a source of increased danger. If their isolation is violated, "close communication" with powerful devices can be fatal. That is why, in order to protect all the inhabitants of the home, in country houses it is imperative to equip electrical grounding. Its arrangement can be entrusted to professionals, or you can do it yourself.

Why is protective grounding necessary?

Professional literature indicates that protective grounding is a connection of non-current-carrying parts of electrical installations to the ground (soil), which is performed intentionally. At the same time, in the normal state, these parts of electrical appliances and installations are not energized. But if a partial destruction of the insulating layer suddenly occurs, the metal case of the device may be energized.

If you explain in a more accessible language, you will have to remember the school physics course. As we know from this, the current tends to flow in the direction where there is the least resistance. When the insulation is broken on the current-carrying parts of electrical appliances, the current begins to look for a place where the resistance is lowest. So it reaches the body of the device, as a result of which the body is energized. This situation is called "breakdown on the hull". In addition to the fact that the current on the case can harm the device itself or disrupt its functionality, if at such a moment a person or animal touches the device case, they will receive an electric shock. This can have dire consequences.

Protective grounding is performed in order to divert current to the ground (ground). At the same time, it is extremely important to make a ground loop with such low resistance that the current, which is distributed in inverse proportion between the person and the grounding device, passes through the person at the maximum allowable rates, and most of it is redirected to the ground.

What is a ground loop

The most common variant of the ground loop is electrodes buried in the ground, connected to each other in some kind of circuit, which can be any geometric figure - a triangle, a square or another, but the connection can also be made in one row. The arrangement option depends on how convenient it is for installation, and on the size of the territory that can be used for the circuit. Sometimes the ground loop is performed along the perimeter of the building. The resulting design is attached to the shield, for which a ground cable is used.

The distance from the ground loop to the house should not be too large, 4-6 m is considered optimal. You cannot place the loop closer than 1 m to the house, it is undesirable to go further than 10 m.

Important! The ground loop must be equipped below the freezing level of the soil, i.e. at a depth of at least 0.8 m.

The depth to which it is necessary to bury the electrodes depends on the structure of the soil and its saturation with water and can range from 1.5 m to 3 m or more. If groundwater is close to the soil surface, the soil is saturated with water, then the depth will be shallow. Otherwise, you will have to drive the rods deep into the ground or equip another version of the grounding system.

Ground loop from black rolled metal

Any ferrous metal rods can be used as ground electrodes. It can be a steel corner (most often used), a pipe, an I-beam, fittings with a smooth structure. The principle of choice is simple - the convenience of driving into the ground. Those. you can choose any shape, the main thing is that the cross section of the metal is at least 1.5 cm2.

The number of rods - electrodes can be determined empirically or made calculations, but the most common is a triangular ground loop with electrodes at the vertices of the triangle. Between themselves, the rods are connected by metal strips, the same strip leads to the switchboard.

The distance between the rods can be from 1.2 m to 3 m or more. It depends on the resistance of the soil.

Important! Before doing grounding in your home, check with regular electricians in your area. Ask them what are the most common designs, and with what characteristics they equip in your area. At what depth to put the electrodes, how far to take out from the house, what distance to make between the rods. This will make your task much easier.

In addition to the fact that it is possible to equip a ground loop from improvised material, ready-made modular grounding systems have appeared on the market.

The set includes rods made of high-quality steel, they are covered with copper on top. The diameter of the rods is about 14 mm, the length is up to 1.5 m. There is a copper-plated thread on both sides of the rod. The elements are interconnected by means of brass couplings. To deepen the rods into the ground, there are tips that are screwed onto the threaded connection. There are several types of such tips for different soils. The kit also includes clamps for connecting vertical (rods) and horizontal (strips) elements. To protect the structure from corrosion, a special paste is used, which processes all elements of the system.

Ready-made modular grounding systems have several significant advantages:

By connecting vertical elements, a depth of 50 m can be carried out;
The rods are not very susceptible to corrosion due to copper plating and stainless steel;
No welding required;
Arrangement can save space, because. the whole system can be equipped on 1 m2;
Installation does not require special equipment;
Durable.

The choice of grounding system, homemade or ready-made modular, depends only on the financial budget and personal preferences. But in any case, before arranging, it is necessary to make grounding calculations.

How to calculate grounding

For those who do not like unnecessary complications, there is an option to perform grounding empirically. You can equip a triangular circuit at the optimal distance from the house, use metal rods 3 m long, make the distance between the rods from 1.5 to 2 m, connect them together and measure the resistance of the circuit. The requirements for grounding are as follows: the resistance of the ground loop must be in the range from 4 to 10 ohms. As a general rule, the lower the resistance value, the better. If the measurement result of our circuit does not meet the requirements, then we add more electrodes and connect them with those already installed. We take measurements again. And so we repeat until our circuit has a resistance of 4 ohms.

A more correct solution would still be to make all the necessary calculations before starting the installation of the circuit. The most important thing is to determine the number of required electrodes and the length of the horizontal ground electrode (strip). All this directly depends on the properties of the soil, or rather its resistance.

First of all, we determine the resistance of one rod.

The value of soil resistivity for calculations can be taken from the table.

If the soil is heterogeneous, then its resistance is calculated by the formula:

The value of the seasonal climate coefficient can be taken from the table:

If we do not take into account the resistance of the horizontal ground electrode (strip), then the number of electrodes can be found by the formula:

We find the resistance of spreading horizon. ground electrode:

The length of the grounding conductor is found by the following formulas:

Final number of electrodes:

The demand coefficient can be found from the table:

The utilization factor indicates the influence of currents on each other, which depends on the location of the vertical ground electrodes. When the electrodes are connected in parallel, the currents passing through them affect each other. The smaller the distance between the vertical electrodes, the greater the resistance of the entire circuit. That is why it is sometimes advised to space the rods from each other at a distance equal to their length, for example, 3m.

The value of the number of electrodes obtained in the course of calculations is rounded up to a whole number. The calculations are ready, you can proceed with the installation.

How to make grounding in a private house with your own hands

Installation of grounding is recommended to start in the warm season. Firstly, it is easier to carry out excavation work. Secondly, the value of soil resistance will be more accurate and maximum. This is very important for good grounding. And then you can make grounding when the soil is temporarily saturated with water, and its resistance will be 4 ohms, and then drought will come and its resistance will increase to 20 ohms. It is better to immediately take into account the maximum value.

We will consider the arrangement of a ground loop made of rolled metal in the form of a triangle:

First of all, choose a convenient place. We dig a trench in the form of a triangle. The optimal depth is from 0.7 to 1 m, width is 0.5 - 0.7 m. The length of each line is the same as we determined in the course of calculations (the length of the horizontal ground electrode).
From one of the corners (any) we dig a trench leading to the power shield near the house.
Vertical grounding - we drive the electrodes into the vertices of the triangle. You can use a steel corner 50 * 50 or any other rod metal. For the convenience of driving into the ground, we sharpen the end of the rod with a grinder. If the soil is too hard to hammer electrodes into it, then we drill wells.
We deepen the rods so that their top sticks out of the ground. If we had to drill wells, then inserting electrodes into them, we fill them with soil mixed with salt.
We weld a steel strip (at least 40 * 5 mm) to the rods so that a triangle forms. We lead one lane along the trench to the power cabinet.
In a private house, we start grounding through a shield. To do this, we attach the strip to the ground wire or directly to the power shield with a 10 mm bolt. The bolt must be welded to the strip.

The next step is to check the grounding. To do this, you need the device "Ohmmeter", it costs a lot. In order to check the resistance once or twice in a lifetime, it is expensive to buy it. Therefore, we invite specialists from the energy department to check the resistance of the circuit. In addition to taking measurements, they will also fill out a ground loop passport. If the resistance indicators are normal, then you can bury the circuit. If not, then we drive in additional electrodes.
We fill up the trench. We use for this homogeneous soil without impurities of crushed stone or construction waste.

Important! In dry weather, it is recommended to water the ground loop with water from a hose, so its resistance decreases.

For better operation of the circuit breaker, neutral grounding is also performed. At the entrance to the building, the neutral is connected to re-grounding. The fact is that electricity comes to private homes through the air. For power transmission towers of 6 - 10 kW, the neutral is re-grounded, but for power lines of 0.4 kW, power companies almost never do this. In order for the load to be distributed correctly, it is necessary to re-ground the support near the house (it is desirable that all neighbors are also grounded). And this grounding should not be combined with the circuit.

If you are not sure that you will do everything correctly, you can contact specialized organizations that will perform all the necessary calculations and installation with skill. If you are an ardent business executive who is used to doing everything with his own hands, well, go for it. Just remember - your creation is designed to protect the whole family.

When living in an apartment building, there are no problems with grounding - each storey electrical panel is a ready-made ground loop. But if you live in a private house or in a country house, it is not necessary to invite paid specialists, because you can make a grounding device in a private house with your own hands. 220 V is a strong current supply, so ignoring grounding is life threatening.

Before you take on the independent production of a ground loop, you need to figure out Why do electrical appliances need to be grounded?. This will help to take a responsible attitude both to the choice of the scheme and materials of the ground loop, and to the process of its manufacture.

Interference protection

The problem of interference concerns mainly owners of high-quality sound reproducing/recording equipment and PCs. The network filters built into such devices “collect” impulse noise from the mains and send them to the chassis of the device, and in the case of a PC, to a metal casing.

A fragment of the PC power supply circuit (the filter is circled in red)

If the body of the device is not connected to the ground (PE terminal on the mains plug), then all interference remains on the casing and creates an electromagnetic field around it, which interferes with signal wires, microphones, headphones.

Anyone who has encountered such a problem knows that it is difficult to get rid of such interference. No shielding and super cables solve the problem - pickup from the case penetrates into external devices even through the shielding braid of the connecting wire. But it is worth connecting the case of the same PC to a central heating battery or water supply, as the background in headphones or speakers disappears in the most miraculous way.

If the interference in sound reproduction is, although serious, but only an inconvenience, then the voltage that has fallen on the casing of the device for one reason or another can be life-threatening. The worst thing is that equipment malfunction during insulation breakdown on the case often does not manifest itself in any way- the device works and looks absolutely fine. But as soon as a person touches the casing of the same washing machine, a current begins to flow through his body into the ground (damp floor, tile, concrete), the value of which is even 50-80 mA is fatal:

Electric shock to a person when touching faulty equipment

To eliminate such a situation, it is enough to connect the body of the device to the ground, and even a faulty washing machine or dishwasher will not pose any threat to a person. With an incomplete breakdown, the voltage from the casing will simply drain into the ground through a special bus, but a complete breakdown of the insulation will cause a short circuit and trigger the protective equipment - a fuse in the device, a machine on the landing or in the house shield.

It is absolutely safe to touch faulty but grounded equipment

For a quick and easy connection to earth, all devices that require earthing are supplied with a special mains plug with earthing contacts or a grounding terminal.

Contacts marked with arrows are grounding

How to make a ground loop

From the foregoing, it can be seen that not only convenience and tranquility, but also people's lives depend on the reliability of grounding. Therefore, the manufacture of the contour must be approached extremely seriously. Do you know how to hold a shovel and a hacksaw in your hands and are you confident in your abilities? Then get to work! But before finding out how to properly make grounding in a private house, it is necessary to decide what to make it from and what design to choose.

Design choice

The main task that needs to be solved in the manufacture of grounding is a good electrical contact of the circuit with the ground. It would seem that the simplest solution is to dig in a voluminous metal object.

If you have a couple of old but strong barrels at your disposal, a rear axle from KAMAZ or something similar, then the option is quite feasible. You weld a metal tire to an object, dig in the object itself, and bring the tire to the surface. But, simple in appearance, this method has a lot of disadvantages:

A much more reliable and durable grounding can be obtained using long pins driven into the ground to a certain depth and electrically connected to each other. The key factor here is the number of pins and their length. By design, these types of grounding are divided:

linear;
voluminous.

Linear grounding consists of a series of pins driven into the ground and connected in series. The volumetric type implies several pins driven in a circle and connected into a ring.

Linear (left) and volumetric types of ground loops

In principle, both types provide high-quality grounding of equipment, a small difference is only in reliability. If one of the jumpers in the linear grounding is broken, a certain number of grounding pins are excluded from operation, which leads to an increase in the resistance of the grounding loop.

The electrical characteristics of the three-dimensional structure are practically not affected. Nevertheless, with high-quality jumpers, the probability of such an accident is small, therefore, when choosing the type of grounding, it makes sense to be guided only by the expediency and convenience of manufacturing a particular design, depending on specific conditions.

Material options

Do not save on materials - after all, your safety depends on their correct choice. As pins, a corner from 40x40 and above is ideal. It is strong enough, which is important when driving, and has a large surface area for minimal contact resistance. If there is no corner at your disposal, then a thick-walled water pipe or a pin with a diameter of at least 15-20 mm will do.

There is an opinion that fittings cannot be used as grounding pins - they allegedly quickly rust. This statement is absolutely groundless - the corrosion resistance of reinforcement is no worse than the resistance of the same corner or pipe, and it is much easier to drive in reinforcement than, say, a soft rod. So if you have rebar with a diameter of 16 mm and above, you can safely use it. In this case, the length of the pins must be at least 2 m, and their number depends on the type of grounding you have chosen, but at least three pieces.

As jumpers, an iron strip (tire) with a width of 15 mm and a thickness of 5 mm is ideal. Such a section was chosen solely for reasons of durability, since even an eight-millimeter wire rod can withstand the emergency short circuit current. It just rots faster and is harder to cook. An ordinary corner or fittings of the corresponding section will also go for jumpers, but this, of course, will cost more. In any case, all materials should not have a dielectric coating - paints, mastics, etc.

Manufacturing process

If you have selected the necessary materials, you have a shovel, a welding machine, a sledgehammer and a hacksaw at your disposal, then you can begin work. The entire manufacturing process of the contour can be reduced to the following basic operations:

Markup.
Trench dig.
Driving in ground pins.
Connecting the pins to each other with jumpers and bringing the grounding bus to the surface.
Trench backfill.
Checking the quality of grounding.

Regardless of the contour design you choose, you must use at least 3 pins located at least 1.5–2 m apart from each other. If your backyard is a continuous lawn, then it is most convenient to use a linear scheme by digging the contour along the wall of a building or garden path.

Having marked the place for the pins, you can proceed to digging a shallow (20–30 cm) trench connecting the marking points. There is no point in digging deeper - a bus laid in a trench will play the role of jumpers, not grounding. It rusts, contrary to the opinion of "specialists", in exactly the same way at any depth. The main purpose of the trench is to hide the tire so that people don't trip over it.

Since there is a lot of free space near the house, the “triangle” scheme was chosen

Now the most responsible and difficult operation is driving in the grounding pins. To do this, their ends must be cut at an angle of about 30 degrees. You can drive in with an ordinary sledgehammer, but some use an ordinary puncher for this purpose.

Ground pins can be driven in with a sledgehammer or puncher

The pins are hammered to the full length, only the ends 10–20 cm long remain on the surface. Jumpers will be welded to them. After all the pins are clogged, they need to be connected to each other with a bus. To do this, it is better to use welding - it is much more durable and reliable than a bolted connection.

A welded connection (left) is less aesthetically pleasing, but much more reliable than a bolted one.

Immediately weld a branch bus to the almost finished structure - the house circuit will be connected to it.

Outlet bus and the option of connecting a house circuit to it

It remains to paint over the welding spots with any paint or mastic, wait for it to dry and fill the trench. If possible, it is advisable to make it with sand for better drainage - and the tire will last longer, and the ground around the pins will be more wet. If sand is unacceptable for technical or aesthetic reasons, then you can use the earth - that's okay. Sleep, plant grass. Question. you decided how to make grounding in a private house, but the circuit must be checked.

Now you need to make sure that the circuit is securely connected to the ground electrically and can act as an emergency ground. For verification, you can call power engineers with special equipment for a fee, but it is quite possible to conduct high-quality tests on our own.

To do this, you will need any powerful electrical appliance with a power of about 1 kW. An electric stove, iron, heater, etc. will do. You also need a voltage indicator (indicator screwdriver), a piece of wire and an AC voltmeter.

Using the pointer, find the phase in the outlet and measure the voltage between it and your ground. Record the instrument readings. Now connect the device between phase and circuit. He should earn quite well. Repeat the measurement and compare with the readings obtained without load. If the voltage under load drops by no more than 10-15 V, then the ground loop can be considered working.

Grounding test circuit (a light bulb is conventionally shown as a load)

If the voltage drop is greater, repeat the measurement operation, but now use the regular zero in the outlet instead of the circuit. It also drops a lot - your electrical wiring cannot cope even with a relatively small load and it's not about grounding. If there is not a big drop, then you will have to add a few more ground pins to your circuit and repeat the tests.

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