How is grounding done in a private house. Do-it-yourself grounding device: simple and complex, for different cases

In order to provide your own private house with a safe power supply system, it is necessary to take into account the grounding system in the process of its reconstruction or when conducting a new electrical wiring scheme. It should be noted that the installation of grounding in a private house with your own hands 220v is not a very complicated process. Especially when compared with installation in an apartment building. And although everyone understands why protective grounding is needed, not everyone does it. Therefore, we will consider the design in full, and at the same time we will answer the question of how to make a ground loop for a country house.

Grounding device on the street near the house

The device of the ground loop in a private house is the pins driven into the ground vertically, which are tied together with conductors. And this whole structure is connected to the switchboard in the house. Before you make grounding in a private house, you need to prepare the necessary tools and materials.

From the tools you will need shovels, scrap, a sledgehammer, a hammer, a welding machine with electrodes, a grinder, wrenches. From materials:

• metal corner with dimensions 50x50x5 mm;
• steel tape 40 mm wide and 4 mm thick;
• metal wire rod with a diameter of 8-10 mm.

Purely in its design, the house ground loop is an equilateral triangle, into the corners of which metal ground electrodes are driven in. For this, a metal corner is used. The driving depth is 2.5-3.0 m. You can do this yourself with an ordinary sledgehammer. If the soil in the area is solid, then you can first make a deepening with a drill to a depth of 1.5 m, and then finish off the corners with a sledgehammer.

The installation process must begin with applying the dimensions and shape of the ground loop to the ground. After that, a trench up to 60 cm wide is dug around the entire perimeter, so that it is convenient to carry out welding, and 80-100 cm deep. Ground electrodes are driven in. In order for the process of entering the corners into the ground without problems, it is recommended to sharpen their ends under a cone. It is not necessary to hammer in all the way, it is necessary that the edges of the pins remain sticking out above the bottom of the trenches, approximately 20-30 cm.

Now it is necessary to dock the corners with each other by horizontal elements of the ground loop. For this, a metal tape is used. The connection is made only by electric welding. No bolts that will corrode underground, and this is a partial or complete lack of contact, which will lead to inefficient grounding in a country house.

The next stage is the connection of the circuit made with the switchboard in the house. To do this, you can use either a wire rod or the same metal strip. In the yard, the connecting circuit is carried out in a trench, inside the house along a wall or plinth. At the end of the conductor that entered the house, an M6 or M8 bolt is welded. A ring of wire responsible for the internal grounding of a private house will be put on it. Fastening is made with a similar nut. Seams may need to be insulated.

Attention! Metal fittings cannot be used as elements of the ground loop. Its outer layer is hardened, which disrupts the uniform distribution of current over the entire profile section. In addition, rebar in the ground rusts faster.

Places of welding must be treated with anti-corrosion compounds. But it is forbidden to paint or cover the entire contour with some kind of protective compounds. Because the system requires full contact with the ground, where stray currents will go.

On this, the installation of the ground loop for a private house can be considered complete. Therefore, make sure that the welding joints are strong, after which it is necessary to dig trenches with shovels. By the way, this technology can also be used to build a lightning rod (lightning rod). Here is a grounding device in a private house you can do yourself.

It should be noted that the correct form of grounding a private house is not necessarily a triangle. You can use square, circle, line and other shapes. It is important that the circuit itself does not create resistance, so the maximum number of ground electrodes driven deep into the earth and their horizontal counterparts was as large as possible. Although the triangle is a time-tested option. And one more important point - the distance from the home circuit of the grounding system to the foundation of the house should not be less than one meter.

Connection in the electrical panel

Usually, private houses are supplied with electric current by overhead power lines. Therefore, the input to the house is made with two wires: phase and zero. Their grounding system is based on the TN-C scheme, in which the installed zero circuit, which is also the grounding one, is connected to a common neutral in a transformer substation.

Since your house is equipped with a grounding system, the connection can be made according to two different schemes:

1. TN-C to TN-C-S;
2. TN-C to TT.

Connecting the circuit according to the TN-C-S scheme

A do-it-yourself grounding system for a private house according to the TN-C scheme is, as a rule, a two-wire wiring, in which one wire is a phase, the second zero performs two functions at once: a working conductor N and protective PE. To transfer to the TN-C-S scheme, it is necessary to install an additional bus inside the switchboard. It must have metal contact with the electrical panel housing. It will be connected to the neutral wire of the mains and the conductor from the new ground loop, assembled by hand.

The new bus must be connected to the bus to which the neutral wire N was connected, leaving the house. In this case, there should be no contact between the N bus and the shield. In fact, this will work out, because a dielectric terminal block is installed in the shield on the bus, through which the connection is made. By the way, the phase wire is also isolated from the elements of the switchboard and its housing.

The last step on how to properly ground in a private house using the TN-C-S system is to connect a new bus and a ground loop to each other. Usually, a copper stranded cable with a cross section of at least 4 mm² is used for this, one end of which is attached to the shield, the other to a bolt welded to the end of the grounding conductor at the entrance to the house.

TT connection

The scheme is similar to the grounding of a house according to the TN-C-S system, but it also has striking differences. In the TT connection system, the incoming PEN conductor, carrying a dual load (neutral and earth), is connected to a busbar that is isolated from contact with the switchboard. As, in principle, and a phase conductor. The neutral wire leaving the house will be connected to it.

A ground wire coming out of the house is connected to an uninsulated bus, which is not connected to other buses. The ground electrode coming from the street ground loop is also connected here. The connection is made with a copper cable with a minimum cross section of 10 mm². That is, it turns out that all the wires pass through different circuits and are connected to each other only in household appliances.

A distinctive feature of the TT grounding system, its positive side is the separation of two circuits: zero and ground. There is one negative point in the TN-C-S system - when the PEN wire burns out, electricity will go through the least resistance, that is, through the protective ground itself. And this is fraught with big troubles. The minimum that can happen is a short circuit in the wiring, household appliances may burn out. As much as possible - here and the fire is not so far away.

Grounding in a private house according to the TT system guarantees complete safety in any non-standard situations. And even if the PEN conductor burns out, then there will simply be no electricity in the house, because the grounding network passes through a separate circuit. And it has nothing to do with zero. Therefore, choosing a grounding system for a TT house (mounted with your own hands), you can be sure of its complete safety.

Grounding check

Grounding in a wooden or brick house is ready, you need to check it. What do I need to do?

• We dismantle any socket in the house.
• Take your multimeter and set it to voltage mode.
• We connect the wires of the phase and zero with the probes of the device. The voltage value in the network should appear.
• Then the phase and ground are connected. The device should show a slightly different (reduced) voltage value than in the previous paragraph.

All this can be done with the help of a control light. All the same manipulations in which the light bulb should burn brightly when the phase is connected to zero, and dimmer when the phase is connected to the ground. This is how you can answer the question of how to check the grounding in a private house.

In connection with the do-it-yourself grounding device at home, private home owners and newly minted developers often face some problems that they cannot solve on their own. For example, do-it-yourself grounding in a private house (380v of input voltage). Are there any particularities in the installation? There are no special features, because the three-phase connection inside the house is divided into single-phase circuits, which are evenly scattered throughout the building. For example, one phase goes to lighting, the second to sockets, the third closes, for example, to a boiler. The house has to be grounded along one circuit. That is, the ground wire coming out of the house is connected to the bus, where the ground electrode was connected from the street. At the same time, inside the premises, the ground loop connects all sockets and powerful household appliances to each other, as separate consumers.

Is it possible to make grounding in the house using a basement or cellar for this? There are no problems here either. The main thing is that the grounding in the basement (cellar) is completely in the ground so that the resistance of the structure is minimal. In this case, the cellar will be an ideal place (wet floor and soil that conducts current well), the only requirement for it is to close the installation site of the circuit with protective devices, for example, lay wooden grates on the floor.

Conclusion on the topic

When installing a grounding scheme in a private house with your own hands for 220v, you must be aware that this is a security measure. And no matter what expenses you have to do, you should not worry that the family budget incurs losses. It will pay off handsomely, because health and life are more expensive. Therefore, you should not hesitate to do grounding in a private house or not. The answer is positive - you need to do grounding without delay. For grounding, you should not skimp, but how it is done is described in detail.

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Or a country cottage is always associated with a large amount of electrical work. In this range of tasks, along with the power supply to the house, the installation of distribution and protective equipment, the laying of internal lines, a well-planned and executed grounding system is no less important. Unfortunately, when carrying out " samostroy"Inexperienced owners quite often forget about this moment or even deliberately ignore it, trying to achieve some kind of false savings in money and labor costs.

Meanwhile, the grounding system is extremely important - it can prevent many troubles that can lead to very sad or even tragic consequences. According to existing rules, electricians will not connect the house to the power line if this system is not in the house or it does not meet the necessary requirements. And the owner, one way or another, will have to decide how to make grounding in the country.

In modern urban buildings, a ground loop is necessarily provided for at the design stage of the building and its internal communications. The owner of private housing will have to decide this issue himself - to invite specialists or try to do everything with his own hands. There is no need to be afraid - all this is quite a feasible task.

Why is a ground loop needed?

In order to understand the importance of grounding, basic concepts from a school physics course are enough.

The vast majority of private houses are powered by a single-phase AC 220 volts. The electrical circuit necessary for the operation of all devices or installations is provided by the presence of two conductors - in fact, a phase and a neutral wire.

The design of all electrical appliances, tools, household and other appliances provides for insulation elements and protective devices that should prevent voltage from entering conductive housings or casings. Nevertheless, the probability of such a phenomenon is never excluded - the insulation can be a discharge, burn out from unreliable, sparking contacts in wire connections, circuit elements, etc. can fail. In this case, the phase voltage can get on the device case, touching which becomes extremely dangerous for humans.

Of particular danger are situations if next to such a faulty device there are metal objects that have the so-called natural grounding - heating risers, water or gas pipes, open elements of reinforcement of building structures and etc.. At the slightest touch to them, the chain can close, and a deadly current will pass through the human body towards a lower potential. Such situations are no less dangerous if a person stands barefoot or in wet shoes on a wet floor or ground - there are also all the prerequisites for shorting the AC circuit from the device case.

One of the pronounced properties of the electric current is that it will necessarily choose a conductor with minimal resistance. This means that it is necessary to create in advance a line with a minimum resistance and zero potential, along which, in the event of a breakdown, the voltage will be safely discharged to the case.

The resistance of the human body is a variable value, depending on individual characteristics, and even on the temporary state of a person. In electrical practice, this value is usually taken as 1000 ohms (1 kOhm). Therefore, the resistance of the ground loop should be many times lower. There is a complex calculation system, but usually they operate with values ​​of 30 ohms for a household electrical network of a private house and 10 ohms if grounding is also used as lightning protection.

It may be objected that all problems can be completely solved by installing special protective devices (RCDs). But for correct operation, grounding is also a necessity. If even the slightest current leakage occurs, the circuit will close almost instantly and the device will work, turning off the dangerous section of the home electrical network.

Some owners are under the prejudice that it is enough to use plumbing or heating pipes for grounding. This is extremely dangerous and absolutely unreliable. Firstly, it is impossible to guarantee effective voltage dissipation - pipes can be heavily oxidized and not have good enough contact with the ground, and besides, they often have plastic sections. It does not exclude electric shock when touching them in the event of a power failure to the case, and neighbors may also be exposed to such a danger.

Most modern electrical appliances are immediately equipped with a power cable with a three-prong plug. Appropriate sockets must also be installed when carrying out wiring work in the house. (Some older appliances have a ground terminal on the case instead.)

There is a strictly defined color "pinout" of wires: the blue wire is definitely "zero", the phase can have different colors, from white to black, and the ground wire is always yellow-green.

And now, knowing this, some “wise” owners, wanting to save money on updating the wiring and organizing a full-fledged grounding, simply make jumpers in the sockets between the zero contact and the ground. However, this does not solve the problem, but rather exacerbates it. Under certain conditions, for example, in case of burnout or poor contact of the working zero in some section of the circuit, or in case of accidental phase reversal, a phase potential will appear on the instrument case, and this can happen in the most unexpected place in the house. The danger of electric shock increases many times in such a situation.

Grounding is a reliable protection against many troubles.

The conclusion from all of the above is that grounding is an indispensable structural element of the home electrical network. It immediately performs the following functions:

• Efficient discharge of voltage leakage from conductive parts, touching which can cause electric shock.
• Equalization of potentials in all objects in the house, for example, grounded appliances and pipes for heating, water supply, gas supply.
• Ensuring the correct operation of all installed safety systems and devices - fuses, .
• Grounding is also important in preventing the accumulation of static charge on the housings of household appliances.
• It is of particular importance for modern electronics, especially computer technology. For example, the operation of switching power supplies for computers is very often accompanied by voltage induction on the cases of system units. Any discharge can lead to failure of electronic elements, malfunctions, loss of information.

Now that the importance of the grounding system has been clarified, we can move on to the question of how to make it in a private house on your own.

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Protective automation

What are the grounding systems in private homes

So, a well-executed grounding system should provide reliable contact with zero ground potential and with the lowest possible resistance of the created circuit. But, gruent -gruntat discord - its different types seriously differ from each other in resistivity:

Soil type	soil resistivity (ohm × m)
Sand (when the groundwater level is below 5 m)	1000
Sand (when the groundwater level is above 5 m)	500
Fertile soil (chernozem)	200
Wet sandy loam	150
Semi-hard or forest-like loam	100
Chalk or semi-hard clay	60
Graphite schist, clayey marl	50
Plastic loam	30
Plastic clay or peat	20
underground aquifers	from 5 to 50

Obviously, those layers that have the lowest resistivity are, as a rule, located at a considerable depth. But even when the electrode is deepened, the results obtained may not be enough. This problem is solved in several ways - from increasing the depth of installation of pin electrodes, to increasing their number, the distance between them or the total area of ​​contact with the ground. In practice, several basic schemes are most often used:

• Scheme "a" - installation of a buried metal closed loop around the perimeter of the house. As an option - shallowly hammered pins connected by a bus around the ring.

In suburban construction, it is used infrequently due to the large amount of earthworks or due to the peculiarities of the location of buildings on the site.

• Scheme "b" is perhaps the most popular among owners of suburban housing. Three or more moderately buried pin electrodes connected by one bus - this design is easy to do on your own, even in a limited space.
• The diagram "c" shows grounding with one electrode installed at a great depth. Sometimes such a system is arranged even in the basement of a building. The scheme is convenient, but not always feasible - it is almost impossible to implement it on rocky soils. In addition, for such a grounding system, you need to use special electrodes - we will talk about it a little lower.
• Scheme "g" is quite convenient, but only if it was thought out at the design stage of the house, and executed during the pouring of the foundation. Bringing it to life on a finished building will be extremely unprofitable.

So, the easiest way to implement with minimal cost schemes "b" or, if possible, "c".

Grounding using homemade metal parts

To make this type of grounding system, you will need metal profiles, a welding machine, earthwork tools, a sledgehammer. In some cases, with complex dense soils, a hand drill may be required.

Schematically, this system looks like this:

Location buried electrodes is selected so that it is most convenient to bring the ground bus to the switchboard. The optimal distance from the house is 3-6 meters. Permissible limits are no closer than one meter and no further than ten.

The dimensions indicated on the diagram are by no means some kind of dogma. So, the side of the triangle can be up to three meters in length, and the depth of driving the pin can be somewhat smaller - 2.0 ÷ 2.5 m. The number of electrodes can also change - if the soil is dense and it is not possible to drive the pins to a great depth, you can increase their number.

A sound advice is to contact your local power supply in advance for recommendations on the implementation of a ground loop. These specialists probably have well-thought-out and tested schemes in this region. In addition, they will be able to help calculate the dimensions based on the planned load of the home electrical network - this also matters.

What can serve as electrodes? For these purposes, a steel corner with a shelf of 50 × 50 mm and a thickness of at least 4 ÷ 5 mm is most often used. Pipes can be used, preferably galvanized with a wall thickness of at least 3.5 mm. It is possible to take a steel strip with a cross-sectional area of ​​​​the order of 48 mm² (12 × 4), but it is more difficult to drive it vertically into the ground. If it is decided to use a steel bar, now and then it is better to take galvanized, with a diameter of at least 10 mm.

To tie the pins into one loop, use a 40 × 4 mm strip or 12 - 14 mm wire rod. The same material is suitable for laying the ground bus to the point of its entry into the house.

• So, initially marking is done at the chosen place.

• Then it is advisable to dig a small pit of the intended shape to a depth of 1 meter. The minimum depth is 0.5 m. At the same time, a trench is dug to the same depth - a ground bus will go along it from the contour to the basement of the house.

• The task can be somewhat simplified by digging not a continuous pit, but only trenches along the perimeter of the contour being created. The main thing is that their width allows for free plugging of electrodes and welding.

• Prepare electrodes of the desired length. The edge with which they will be driven into the ground must be sharpened with a grinder, cutting it at an angle. The metal must be clean, unpainted.

• In the designated places, the electrodes are driven into the ground using a sledgehammer or an electric hammer. They are deepened so that in the pit (trench) they protrude above the surface level by about 200 mm.

• After all the electrodes are clogged, they are connected with a common bus (horizontal ground electrode) from a metal strip 40 × 4 mm. Only welding is applicable here, although you can find recommendations to get by with a bolted connection. No, in order to ensure reliable and durable grounding, this harness must be welded - the threaded contact located underground will quickly oxidize, the loop resistance will increase sharply.

• Now you can lay a tire from the same lane to the foundation of the house. The busbar is welded into one of the clogged electrodes and placed in a trench, then it enters the basement of the building.
• The tire is attached to the plinth. Not shown in the figure, but it is advisable to provide a slight bend in front of the attachment point, so-called"compensation hump" to compensate for the linear expansion of the metal during temperature changes. At the end of the strip, a bolt with an M10 thread is welded. A copper terminal with a ground wire will be attached to it, which will go to the switchboard.

• To pass the wire through the wall or through the base, a hole is drilled and a plastic sleeve is inserted into it. The wire is copper, with a cross section of 16 or 25 mm² (it is better to check this parameter with specialists in advance). It is also better to use copper nuts and washers for connection.

• Sometimes they do it differently - a long steel pin is welded to the tire, so that it passes through the wall of the house, also through the sleeve. In this case, the terminal part will be in the room and will be less susceptible to oxidation under the influence of high humidity.

Bronze distribution plate for earth wires

• The ground wire is connected to the electrical switchboard. For further “distribution”, it is best to use a special plate made of electrical bronze - all ground wires going to consumption points will be attached to it.

Do not rush to immediately fill the mounted circuit with soil.

- It is recommended, firstly, to capture it in a photograph with reference to the surrounding stationary ground objects - this may be required to make changes to the project documentation, as well as to carry out control and verification activities in the future.

- Secondly, it is necessary to check the resistance of the resulting circuit. For these purposes, it is better to invite specialists from the energy supply organization, especially since their call, one way or another, will be necessary to obtain permits.

If the test results show that the resistance is high, it will be necessary to add one more or even more vertical electrodes. Sometimes, before checking, they also go for tricks, abundantly watering the places near the corners nailed into the ground with a saturated solution of ordinary table salt. This will certainly improve performance, however, do not forget that salt activates metal corrosion.

By the way, if you can’t hammer in the corners, then they resort to drilling wells to the desired depth. After installing the electrodes, they are filled with clay soil with the highest possible density, into which they are also mixed with salt.

After the operability of the ground loop has been verified, it is necessary to treat the welds with an anti-corrosion compound. The same can be done with the bus going to the building. Then, after the mastic has dried, the pit and trenches are covered with soil. It should be homogeneous, not littered and without crushed stone inclusions. Then the place of backfilling is carefully compacted.

Video: installation of a ground loop using a metal corner

Use of ready-made factory kits

Prefabricated ready-made kits are very convenient for organizing grounding in the country. They are a set of pins with couplings that allow you to increase the depth of immersion into the ground as you drive.

This grounding system provides for the installation of one pin electrode, but to a greater depth, from 6 and even up to 15 meters.

The kit usually includes:

• Steel pins 1500 mm long with a galvanized or copper-plated surface, or made of stainless steel. The diameter of the pieces may vary in different sets - from 14 to 18 mm.

• For their connection, they are equipped with threaded couplings, and for the convenience of penetration through the ground, a steel tip is included in the kit.

In some kits, the couplings are not threaded, but pressing. In this case, one end of the grounding pin is tapered by forging and has a ribbed surface. During impact, a strong connection occurs and a reliable electrical contact between the rods is achieved.

• To transfer the impact, a special nozzle (dowel) made of high-strength steel is provided, which will not be deformed by the impact of the hammer.

Nagel - a nozzle that will transmit the impact force from the hammer

• Some kits provide for a special adapter that allows you to use a powerful hammer drill as a driving tool.

To install such a grounding system, it is also advisable to dig a small pit up to a meter deep and the same in diameter, although some even prefer outdoor placement.

The pins are sequentially driven in with an extension to the desired depth.

Then left on the surface section (about 200 mm) a brass contact clamp is put on.

Either a conductive bus made of a metal strip is inserted into it, or a ground cable with a cross section of 25 square meters is immediately inserted. mm. For connection with a steel strip, a special gasket is provided, which does not allow for electrochemical contact between the ground of the rod and steel (zinc). In the future, the bus or cable is brought into the house and connected to the switchboard in the same way as described above.

Video: driving stick electrodes manually

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Accessories for lightning protection and grounding

What type of rod coating to choose - galvanized or copper-plated?

• From the point of view of economy, galvanizing with a thin layer (from 5 to 30 microns) is more profitable. These pins are not afraid of mechanical damage during installation, even deep scratches left do not affect the degree of protection of iron. However, zinc is a fairly reactive metal, and while protecting the iron, it oxidizes itself. Over time, when the entire zinc layer has reacted, the iron remains unprotected and is quickly “eaten away” by corrosion. The service life of such elements usually does not exceed 15 years. And making the zinc coating thicker costs a lot of money.

• Copper, on the contrary, without entering into reactions, protects the iron it closes, which is more active from the point of view of chemistry. Such electrodes can serve for a very long time without sacrificing efficiency, for example, the manufacturer guarantees their safety in loamy soil up to 100 years. But during installation, care should be taken - in places where the copper plating layer is damaged, a corrosion area will most likely occur. To reduce the likelihood of this, the copper plating layer is made thick enough, up to 200 microns, so such pins are much more expensive than conventional galvanized ones.

What are the general advantages of such a grounding system kit with one deep-seated electrode:

• Installation is not particularly difficult. No bulky earthworks are required, no welding machine is needed - everything is done with a common tool that is in every home.
• The system is very compact, it can be placed on a tiny "patch" or even in the basement of the house.
• If copper-plated electrodes are used, then the service life of such grounding will be calculated in several tens of years.
• Due to good contact with the ground, a minimum electrical resistance is achieved. In addition, the efficiency of the system is practically not affected by seasonal conditions. The level of soil freezing accounts for no more than 10% of the electrode length, and winter temperatures cannot adversely affect conductivity in any way.

Of course, there are also disadvantages:

• This type of grounding cannot be implemented on rocky soils - most likely, it will not be possible to drive the electrodes to the required depth.
• Perhaps someone will be scared away by the price of the kit. However, this is a question from with porn, since high-quality rolled metal for a conventional grounding scheme is also expensive. If we add the duration of operation, the simplicity and speed of installation, the absence of the need for a specialized tool, then, quite possibly, such an approach to solving the problem of grounding may seem even more promising from the point of view of efficiency.

Video: how to make grounding in a country house using a modular pin system

The article will address the issue of a grounding device in a private house, cottage or small do-it-yourself production. Many people mistakenly believe that grounding is an unnecessary, additional thing that, out of harm, is required by the power supply organization or inspection inspectors.

The most important thing that any consumer of electricity should understand is that grounding is an integral part of any power supply. This is the same necessity as the installation of circuit breakers in the switchboard, metering device and other equipment.

To qualitatively perform grounding, it is necessary to carry out a large amount of earthwork. Roughly calculate that at least you will have to manually dig one cubic meter of earth. You will also need a welding machine and welding skills.

The best option is to do the grounding with your own hands, since not all electricians like to do this, and those who do, for the most part, do it poorly.

And so, how is the ground loop done correctly?

There are two most common ground loop options - a triangle and a linear one, in the form of a continuous strip along the house.

Both are correct. Which one to choose, you decide for yourself, based on the free space near the house.

Ground Loop Material

The ground loop consists of vertical and horizontal ground electrodes.
The material from which Not recommended make vertical grounding conductors:

Of what can do:

The end of the corner or round steel is cut at an angle of 30 degrees. This is the most optimal angle for steel to enter the ground.

The horizontal ground electrode is made of 40*4 steel strip.

Dimensions and distances for earth electrodes

Mandatory conditions that must be observed when installing grounding in a private house:

• • ⚡ the length of the electrode that is driven into the ground. It should be at least 2.5-3 meters

Initially, it is better to take an electrode 3 m long. Since in the process of hammering it with a sledgehammer, the part on which the blow is struck will be flattened. In the end, you will have to cut off a few centimeters of such a flattened electrode with a grinder.

• • ⚡ distance between electrodes. It should also be 2.5-3 meters

Regardless of what kind of contour you have - in the form of a triangle or a straight line. This is due to the phenomenon of current spreading from grounding conductors. If the electrodes are clogged closer than 2.5m, then it makes no difference how many electrodes you clog.

They will work almost like one electrode.

• • ⚡ deepening of the trench from the planning mark of the earth - 0.7-0.8m

A trench is a place for laying a strip that connects the electrodes. With a smaller trench depth, the strip will be exposed to precipitation and a rapid corrosion process. With a greater deepening - again there is a risk of exposure to dampness from groundwater.

• ⚡ distance of the ground loop from the foundation of the house - at least 1 m
• ⚡ after excavation of the trench, it is sprinkled with sand for better water drainage from the horizontal ground electrode.

Deepening of electrodes

When all the material and trenches are ready, the process of clogging the electrode begins. To facilitate the process, a little water is poured into the pit. The vertical electrode can be hammered in two ways:

Initially, the upper end of the electrode will be at a high altitude. Therefore, a stepladder is required.

It is not necessary to drive the entire electrode into the ground to the end. Leave at least 20 cm on the surface, as a strip will need to be welded in this place. The length of the welding seam is at least 6-10 cm. The seam itself is dyed.

Never paint the horizontal and vertical ground electrodes.

Thus, you will increase the ground resistance and worsen the connection to the ground.

To improve the ground loop, you can connect it to existing metal structures buried in the ground - for example, with a fence.

Ground connection to electrical panel

When the circuit is made, it must be connected to the electrical panel. Here you can already use not a strip, but a wire with a diameter of 10 mm. It is connected with a horizontal ground electrode by welding, and with the shield body by means of a bolted connection.

You can also bring a strip of a horizontal grounding conductor to the surface near the shield, and having welded a bolt to the strip, connect the circuit with the shield one with a copper conductor with a cross section of 10 mm2. The bolted connection must be on the surface and accessible for revision.

After checking the reliability of the connection of the welds, the trench is covered with earth. This completes the installation of the ground loop.

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

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

materials

1. Steel corner 50 x 50 x 4 mm X 3 m - 3 pcs.
2. Steel corner 50 x 50 x 4 mm X 1.5 m - 3 pcs.
3. 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).
4. Electrodes 3 mm.
5. Wire 4 x 4 mm 2 - length, from soldering with a rod, to the shield.
6. Corrugated pipe for cable - length, from desoldering with a rod, to a shield.
7. 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.

1. Pole wires powering the house.
2. Rod 14 mm. It comes out of the ground and rises to the place of desoldering and lightning protection.
3. The place of desoldering (connecting) grounding, and power wires from the pole.
4. 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.

1. Corrugated wire - ground with zero and 3 phases entering the house.
2. 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 inevitably 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.

All household electrical appliances not only make our existence comfortable, but also pose a certain danger to human health. Therefore, in a network of any voltage class (220 V or 380 V), it is always necessary to provide for grounding in a private house, how to do it, we will tell further.

Why is grounding necessary?

Grounding in an electrical network is based on elementary physical laws and is a universal system for protecting a person from electric shock, as well as a system for protecting electrical equipment of any purpose from insulation breakdown (zeroing). Operation of electrical networks without grounding is potentially a fire hazard. The arrangement of a private house with a ground loop is a prerequisite for the safe use of any electrical appliances and apparatus.

According to the rules for the installation of electrical installations (hereinafter PUE), which apply to all types of electrical installations, protective grounding must be provided.

1.7.56. To prevent electric shock in case of insulation damage, the following protective measures should be used alone or in combination in case of indirect contact:

Protective grounding (1.7.63, 1.7.65, 1.7.66);

Automatic power off (1.7.61, 1.7.63);

Potential equalization (1.7.78);

Class II equipment or equivalent insulation (1.7.86, 1.7.87);

Protective electrical separation of circuits (1.7.86, 1.7.88);

Insulating (non-conductive) premises, zones, sites (1.7.86, 1.7.89);

Systems of extra-low (low) voltage SELV, ZSNN, FSNN (1.7.68–1.7.70);

Potential equalization (1.7.65, 1.7.66).

PUE-2009

For an objective understanding, you need to understand the following terms, according to the PUE:

• direct touch- electrical contact of people or animals with current-carrying parts under voltage, or approaching them at a dangerous distance.
• indirect touch- electrical contact of people or animals with an open conductive part that has become energized as a result of damage to the insulation.
• Protection against direct contact- protection that prevents electric shock in the absence of damage to the insulation of conductors.
• Protection against indirect contact- protection that prevents electric shock in the event of a single damage.
• grounding conductor- a conductive part (conductor) or a set of interconnected conductive parts (conductors) that are in electrical contact with the ground directly or through an intermediate conductive medium, such as concrete.
• Ground conductor- a conductor connecting the earth electrode to a certain point in the system or electrical installation or equipment.
• Grounding device- a set of electrically interconnected grounding conductors and grounding conductors, including elements of their connection.

grounding- making an electrical connection between a specific point in a system or plant or equipment and local earth.

Note. The connection to the local ground can be intentional, unintentional and accidental, as well as permanent or temporary.

After making sure of the need for grounding, you can begin to consider the issue of self-equipping a private house with a ground loop.

What types are there

First of all, you need to understand what kind of grounding you need to install. The decisive factor in the decision will be the voltage class in a private house (220 V or 380 V).

According to its purpose, there are two types of grounding: protective and working.

Working- is performed in order to prevent a sudden increase in voltage in household electrical appliances. This can happen as a result of a violation of the insulation of the transformer windings. And also this type of grounding protects electrical appliances from lightning entering the building structure. In this case, the entire charge goes to the ground.

Protective earth- is carried out due to the forced connection of the body of the electrical appliance to the ground through a conductor.

Protective earthing must be provided for the following household appliances:

• washing machine- its body has a relatively large electrical capacity due to operation in conditions of high humidity.
• microwave- the main working element of the furnace is the magnetron. It has great power. If the ground connection in the socket is poor, then an increase in the level of magnetic emissions may occur. Many microwave oven manufacturers equip a ground terminal on the back of the oven.

To contact the grounding conductor in the network and the electrical appliance, modern sockets are equipped with grounding contacts.

Grounding in a household electrical network

There are six grounding systems to provide grounding. In individual building structures, in particular residential buildings, two main grounding systems are used.

TN-S-C system- recommended for implementation in recent years. Such a scheme was made with a dead-earthed neutral at a substation. The equipment in this case has direct contact with the ground. To the consumer itself, earth (PE) and neutral / zero (N) are led by one conductor (PEN). At the entrance to the power grid of a private house, such a conductor is divided into two independent conductors.

Such a system does not provide for the mandatory installation of a residual current device (RCD). Protection is carried out by automatic switches.

The disadvantage of such a system is that if the PEN conductor is damaged or burnt out throughout the substation / house section, a phase voltage appears on the grounding bus of the house. There is no such thing as tension. Based on this, the PUE regulates stringent requirements for such a line: the PEN conductor must be provided with mechanical protection, and periodic local grounding must also be equipped on the power line supports.

Many transmission lines, especially in rural areas, do not meet the above conditions. For such a case, another earthing system is recommended - the TT system.

circuit diagram

Such a grounding system is implemented due to a separately running wire from the ground loop to the input shield of the building, and not from the transformer substation. This system is more resistant to damage to the protective conductor, but requires the installation of an RCD. Without equipping the system with such devices, there is no protection against electric shock. In this regard, the PUE recommends such a system only as an additional one to the TN-S-C system. (If the line does not meet the requirements of the TN-S-C system).

General form

Grounding difference for 220V and 380V networks

Differences in the grounding systems of private houses with an operating voltage of 220 V or 380 V are not significant. In both cases, a ground loop is constructed. The difference lies in the way the circuit is connected to the home electrical network.

In the 220V network - the voltage is single-phase. In this case, a three-wire conductor and sockets with three contacts (phase, zero, ground electrode) are used.

For 220 V network

In a network of 380 V - three-phase voltage. In this case, a five-wire conductor and sockets with five contacts are used (phase - 3 pcs, zero, ground electrode).

For 380 V network

Kinds

The main purpose of the ground electrode is direct electrical contact with the ground. The grounding device (grounding loop) includes a grounding conductor and a set of all conductors connected to it. Including elements of their compounds.

Grounding conductors are of two types:

• natural - metal structures located at a sufficient depth in the ground or reinforced concrete foundation of the building;
• artificial - a direct-purpose metal structure independently installed in the ground;

Artificial ground electrodes are distinguished by their design features.

The combined installation scheme of the grounding device (circuit) is the most effective. When installing in compliance with the necessary rules, such a circuit will be reliable and durable.

How to make a ground loop for a private house with your own hands

The most popular protective circuit design today is the delta circuit. It is made by connecting three pins buried in the ground with a metal strip. Such a scheme is characterized by increased reliability. If the steel connecting strip is broken or damaged on one side, the circuit will continue to function due to the contact on the other side.

Triangle scheme

For the manufacture and installation of the ground loop, you will need the following materials and tools:

Materials:

• steel corner 50–70mm, h=4mm, 3 pcs. the length of one corner is at least 2 meters;
• steel strip 50–70 mm, h = 4 mm, 4 m. for connecting pins from a corner;
• steel strip 30 mm, h=4mm. for electrical connection of the ground loop and the inlet shield of the building. The length depends on local conditions;
• electrodes 3mm.

Tool:

• shovel, crowbar, earthmoving drill for arranging holes in the ground;
• grinder for cutting metal blanks;
• metalwork tool (hammer, sledgehammer, file, screwdriver, clamp) for processing and mounting workpieces;
• welding machine;
• measuring tool (tape measure, square) for marking workpieces;

The joints of the blanks of the grounding loop should be made exclusively by welding. This is regulated by the requirements of the PUE. This type of connection provides the most efficient electrical contact and is most resistant to corrosion.

Work with power tools should be using the necessary protective equipment: glasses, overalls. Work safety first.

When working on the preparation of a corner, it is better to cut one end at an acute angle. Such a corner will be easier to hammer into the ground.

Ground loop pins

Consider the process of installing the ground loop in stages.

This completes the installation of the ground loop. The following is the process of connecting it to the power supply network of a private house.

After connecting the loop to the PE conductor of the electrical network, a test of the loop should be performed. To do this, use special electrical measuring instruments. Such equipment is quite expensive. Therefore, a more simplified version of the circuit health check is used.

This method is carried out by connecting an incandescent lamp (100 W) to the network as follows: the phase wire is placed on the phase contact of the socket, and the neutral wire is placed directly on the circuit design. In this case, you need to pay attention to the intensity of the lamp. A bright light indicates the correct operation of the circuit. Dull, about poor-quality contact at the junction of the metal elements of the circuit. In this case, the connections should be reinforced with an additional welding seam.

Using an incandescent lamp

When determining the resistance value of the protective grounding circuit with a special device, it must be remembered that the value of grounding should not exceed 4 ohms. If its value is greater, then this may indicate poor contact of the circuit with the ground. To eliminate this problem, you can fill the ground with water at the place where the pins are clogged. Due to this, the soil will be compacted and the contact area will increase.

Grounding device calculation

The grounding device is also calculated from the condition of the maximum value of the resistance of the protective ground loop. Which should not exceed 4 ohms. The best option would be the resistance value of an artificial ground electrode, not exceeding 1 ohm.

It is almost impossible to carry out a thorough calculation of the ground electrode at home, without special knowledge and technical literature. Since it provides for the experimental determination of soil resistivity, taking into account correction factors that take into account the drying and freezing of the soil. Determination of the spreading resistance value. Element-by-element calculation of the resistance of the circuit based on its geometric dimensions, depth of occurrence and soil moisture. The coefficient of use of vertical grounding. The presence of natural grounding. And other.

It is better that this is done by specialized organizations that issue a protocol on the suitability of the ground loop and on the compliance of its characteristics with regulatory documents.

There is a simplified method.

Simplified calculation of the ground conductor:

For a vertical earthing electrode (single), the following formula is used:

R1=0.84*p/L where:

R1 - grounding resistance, Ohm;

p - soil resistivity, Ohm*m;

L - length (depth) of the ground electrode;

For multiple vertical ground pins (electrodes):

R=R1/0.9*n where:

R - resistance of one electrode, Ohm;

n is the number of electrodes in the ground loop;

Thus, if the soil resistivity (p) is known, then the resistance of one electrode (R1) is calculated using the first formula. The resulting value is substituted into the second formula and the number of electrodes (n) is determined, with a set length (L).

In the case when the specific soil penetration is not known, you can use the reference table:

Values ​​for common soils

If in practice it was not possible to find or measure the value of the resistivity of the soil in the area for mounting the circuit, the test immersion method of the electrode is used. The method consists in periodically measuring the resistance of the electrode as it sinks into the ground. You can stop clogging the electrode when the resistance indicators have stopped decreasing. This means that the electrode has reached a depth at which the soil resistivity becomes constant. In the future, this electrode must be connected with a metal strip to other elements of the circuit.

Choice of mounting location

Its efficient and safe operation largely depends on the correctly selected place for arranging the circuit. There are several recommendations for this:

• It is impossible to place the ground loop in a place where people or animals are constantly or frequently located. At the moment of insulation breakdown and voltage discharge to the ground, a person or animal in the immediate vicinity may suffer. It is better to take measures to protect such an area.
• Some experts recommend placing the contour on the north side of the building. This is due to the more humid damp in this area.
• If the soil is too wet and there is a high probability of corrosion of the metal of the circuit, then it is better to make it from steel of a large section. And also the design of the circuit can be covered with special conductive materials that will protect against corrosion, but will not impair electrical contact with the ground.
• Do not place the ground loop close to heat communications. Overdried negatino soil affects the resistance of the circuit.
• It is forbidden to locate the circuit in close proximity to a gas pipeline running in the ground.
• The depth of the contour should be below the freezing level of the soil, but not less than 0.5 m.

Earthworks and structural assembly

Earthworks must be carried out carefully. Beforehand, you should consider the perimeter of the work, taking into account the possible occurrence of communications for various purposes in the ground: pipelines, telephone lines, cable power lines. It is better to position the outline away from such objects.

Ground work is carried out using standard tools: shovels, scrap, drill.

Installation of the ground loop

When arranging trenches, they must be made wide enough. This is necessary for the convenience of performing welding work. Indeed, the efficiency of the protective grounding system largely depends on the quality of the welding joints.

A bolted connection is allowed to be used only at the point where the steel strip is brought out directly to the house and connected to the incoming electrical panel.

In some factory-made earthing switches, bolted connections are used, but high-quality contact in these cases is achieved due to pressure plates and copper-plated electrode surfaces.

Connection of copper-plated contour elements with pressure plates

Welding joints must be continuous, the length of the welding seam is at least 100 mm.

For clarity, there is a video that shows the process of arranging a protective ground loop in a private house.

The video is taken from the Youtube Internet resource, is used for informational purposes and is not an advertisement.

Video: self-installation of the ground loop

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