Correct grounding arrangement. How to properly ground in a private home

Modern household appliances and equipment require grounding. Only in this case will manufacturers maintain their guarantees. Residents of apartments have to wait for the networks to be overhauled, while home owners can do everything themselves. How to make grounding in a private house, what is the procedure and connection diagrams - read about all this here.

In general, ground loops can be in the form of a triangle, rectangle, oval, line or arc. The best option for a private home is a triangle, but others are also quite suitable.

Grounding in a private house - types of grounding loops

Triangle

Grounding in a private house or country house is most often done with a contour in the form of an isosceles triangle. Why is this so? Because with such a structure on a minimal area we get maximum area dissipation of currents. The costs of installing a grounding loop are minimal, and the parameters correspond to the standards.

Minimum distance between the pins in the ground loop triangle - their length, the maximum is twice the length. For example, if you drive the pins to a depth of 2.5 meters, then the distance between them should be 2.5-5.0 m. In this case, when measuring the resistance of the ground loop, you will get normal values.

During work, it is not always possible to make the triangle strictly isosceles - stones come across in the right place or other difficult-to-pass areas of soil. In this case, you can move the pins.

Linear ground loop

In some cases, it is easier to make a ground loop in the form of a semicircle or a chain of pins lined up (if there is no free area of suitable dimensions). In this case, the distance between the pins is also equal to or longer the electrodes themselves.

With a linear contour it is necessary larger number vertical electrodes - so that the dissipation area is sufficient

The disadvantage of this method is that to obtain the desired parameters, a larger number of vertical electrodes is required. Since hammering them in is still a pleasure, if there is a meta, they try to make a triangular outline.

Ground loop materials

For the grounding of a private house to be effective, its resistance should not be more than 4 ohms. To do this, it is necessary to ensure good contact of the grounding conductors with the ground. The problem is that ground resistance can only be measured with a special device. This procedure is carried out when putting the system into operation. If the parameters are worse, the act is not signed. Therefore, when doing the grounding of a private house or cottage with your own hands, try to strictly adhere to the technology.

Pin parameters and materials

Grounding pins are usually made of ferrous metal. Most often, a rod with a cross-section of 16 mm or larger or a corner with parameters 50 * 50 * 5 mm (5 cm shelf, metal thickness - 5 mm) is used. Please note that reinforcement cannot be used - its surface is hardened, which changes the distribution of currents, and in addition, in the ground it quickly rusts and collapses. What is needed is a rod, not reinforcement.

Another option for arid regions is thick-walled metal pipes. Their lower part is flattened into a cone, and holes are drilled in the lower third. To install them, holes of the required length are drilled, since they cannot be driven in. When soils dry out and grounding parameters deteriorate, a saline solution is poured into the pipes to restore the dissipative capacity of the soil.

The length of the grounding rods is 2.5-3 meters. This is sufficient for most regions. More specifically there are two requirements:

Specific grounding parameters can be calculated, but the results of a geological study are required. If you have any, you can order a calculation from a specialized organization.

What to make metal connections from and how to connect them with pins

All pins of the circuit are connected to each other by metal bonding. It can be made from:

copper wire cross section less than 10 mm 2;
aluminum wire with a cross-section of at least 16 mm 2
steel conductor with a cross section of at least 100 mm 2 (usually a strip of 25 * 5 mm).

Most often, the pins are connected to each other using a steel strip. It is welded to the corners or heads of the rod. It is very important that quality weld was high - this determines whether your grounding will pass the test or not (whether it meets the requirements - resistance less than 4 ohms).

When using aluminum or copper wire, a large cross-section bolt is welded to the pins, and the wires are already attached to it. The wire can be screwed onto a bolt and pressed with a washer and nut, or the wire can be terminated with a connector suitable size. Main task the same thing - to ensure good contact. Therefore, do not forget to clean the bolt and wire before pure metal(can be sanded) and pressed well - for good contact.

How to make grounding yourself

After all materials have been purchased, you can begin the actual manufacture of the ground loop. First, cut the metal into pieces. Their length should be about 20-30 cm longer than the calculated one - when driven in, the tops of the pins bend, so you have to cut them off.

Sharpen the clogged edges of the vertical electrodes - things will go faster

There is a way to reduce the resistance when driving electrodes - sharpen one end of the angle or pin at an angle of 30°. This angle is optimal when driving into the ground. The second point is to weld a metal pad to the upper edge of the electrode, from above. Firstly, it is easier to hit, and secondly, the metal is less deformed.

Work order

Regardless of the shape of the contour, it all starts with excavation work. It is necessary to dig a ditch. It is better to make it with beveled edges - this way it crumbles less. The order of work is as follows:

Actually, that's all. We did the grounding in a private house with our own hands. All that remains is to connect it. To do this, you need to understand the grounding organization diagrams.

Inserting a ground loop into the house

The ground loop must somehow be connected to the ground bus. This can be done using a steel strip 24*4 mm, copper wire with a cross-section of 10 mm2, aluminum wire with a cross-section of 16 mm2.

If wires are used, it is better to look for them in insulation. Then a bolt is welded to the circuit, and a sleeve with a contact pad (round) is put on the end of the conductor. A nut is screwed onto the bolt, a washer is screwed onto it, then a wire, another washer is placed on top, and the whole thing is tightened with a nut (picture on the right).

How to bring “earth” into the house

When using a steel strip, there are two options - bring a tire or wire into the house. I really don’t want to pull a steel tire measuring 24*4 mm - it looks unaesthetic. If there is, you can use the same bolted connection conduct a copper busbar. It needs a much smaller size, it looks better (photo on the left).

You can also make a transition from a metal bus to a copper wire (cross section 10 mm2). In this case, two bolts are welded to the tire at a distance of several centimeters from each other (5-10 cm). The copper wire is twisted around both bolts, pressing them with a washer and nut to the metal (tighten as best as possible). This method is the most economical and convenient. It doesn't require as much money as using only copper/aluminum wire, and it's easier to run it through the wall than a busbar (even a copper one).

Grounding schemes: which one is better to make?

Currently, in the private sector, only two grounding connection schemes are used - TN-C-S and TT. For the most part, a two-core (220 V) or four-core (380 V) cable (TN-C system) is suitable for the house. With such wiring, in addition to the phase (phase) wire, there is a protective conductor PEN, in which neutral and ground are combined. At the moment, this method does not provide adequate protection against electric shock, so it is recommended to replace the old two-wire wiring with a three-wire (220 V) or five-wire (380 V).

In order to obtain normal three- or five-wire wiring, it is necessary to separate this conductor into ground PE and neutral N (in this case, an individual ground loop is required). This is done in the entrance cabinet on the facade of the house or in the accounting and distribution cabinet inside the house, but always before the meter. Depending on the separation method, either the TN-C-S or TT system is obtained.

Installation of a TN-C-S grounding system in a private house

When using this circuit, it is very important to make a good individual ground loop. Please note that with the TN-C-S system, protection against electric shock requires the installation of RCDs and breakers. Without them, there is no talk of any protection.

Also, to ensure protection, it is necessary to connect all systems that are made of conductive materials - heating, water supply, foundation reinforcement frame, sewerage, gas pipeline (if they are made of metal pipes) to the earth bus with separate wires (inextricable). Therefore, the grounding bus must be taken “with a reserve”.

To separate the PEN conductor and create grounding in a private house TN-C-S, three buses are needed: on a metal base - this will be a PE (earth) bus, and on a dielectric base - this will be an N bus (neutral), and a small splitter bus for four " seating places.

The metal “ground” bus must be attached to the metal body of the cabinet so that there is good electrical contact. To do this, at the fastening points, under the bolts, the paint is removed from the body to bare metal. The zero bus - on a dielectric base - is best mounted on a DIN rail. This installation method fulfills the basic requirement - after separation, the PE and N buses should not intersect anywhere (should not have contact).

Grounding in a private house - transition from the TN-C system to TN-C-S

The PEN conductor coming from the line is connected to the bus splitter.
We connect the wire from the ground loop to the same bus.
From one socket with a copper wire with a cross-section of 10 mm 2 we place a jumper on the ground bus;
From the last free socket we place a jumper on the zero bus or neutral bus (also 10 mm2 copper wire).

Now that's it - grounding in a private house is done according to the TN-C-S scheme. Next, to connect consumers, we take the phase from the input cable, zero from the N bus, and ground from the PE bus. We make sure that ground and zero do not intersect anywhere.

Grounding according to the TT system

Converting a TN-C circuit to TT is generally simple. There are two wires coming from the pole. The phase conductor is further used as a phase, and the protective PEN conductor is attached to the “zero” bus and is then considered zero. The conductor from the made circuit is directly supplied to the grounding bus.

Do-it-yourself grounding in a private house - TT diagram

The disadvantage of this system is that it provides protection only for equipment that requires the use of an “earth” wire. If there are also household appliances made using a two-wire circuit, they may be energized. Even if the housings are grounded with separate conductors, in case of problems, the voltage may remain at “zero” (the phase will be broken by the machine). Therefore, of these two schemes, TN-C-S is preferred as it is more reliable.

Grounding is a mandatory element of organizing the electrical wiring of a private home. After all, in the event of an unexpected breakdown of electricity, it is grounding that protects against electric shock. And those who have tried to grab a washing machine connected to the network from behind know how its open metal parts “pinch” noticeably.

Except washing machine It is advisable to ground directly, and not through a European socket:

microwave ovens– if there is poor contact with the socket, it can shock quite noticeably, which is why almost all models have a separate grounding screw terminal on the back;
electric stoves (ovens and hobs) – due to the high power, the probability of breakdown is very high, so grounding through the socket is not enough;
personal computers - are grounded using any mounting screw on the back of the case, which allows you to remove floating potentials and improve the speed of wireless Internet.

In addition, electrical appliances and lightning protection (if there is an SPD) can be connected to one grounding circuit, which will save time and effort during construction.

What you need to know about grounding

Before you start assembling a ground loop with your own hands, you need to understand the terminology. The circuit itself consists of grounding conductors and metal connections. Grounding conductors are metal pins 2-3 m long, completely immersed in the ground. And the metal connection connects these pins and the distribution board in the house.

It is strictly forbidden to use reinforcement for the grounding loop - insufficient cross-sectional diameter and ribbed surface quickly lead to rusting of the structure and loss of grounding properties.

Therefore, when choosing a metal connection, you need to decide in advance on the circuit diagram and the method of introducing the grounding conductor into the house.

Ground loop schemes - their advantages and disadvantages

The reliability and durability of the entire structure will depend on the chosen scheme. So, conditionally, the contours are divided into:

linear - when the grounding electrodes are laid in a row and connected to each other in series;
with a closed loop (triangular, square, oval) – when all grounding conductors are connected in a closed circle.

The linear circuit is a little simpler to implement - one less connection is needed and does not require much space. Installation of grounding conductors laid in a row can be done even along the foundation blind area (but not closer than 1.2 m from the edge). But a closed circuit is more reliable - even if one connection fails, the circuit will work, because the circuit will not open.

Types of grounding connection to the distribution panel

Connection to the power line, for the most part, occurs via overhead lines. The grounding of the lines in this case is carried out according to the TN-C system, when two wires are supplied to the house - phase (L) and zero (combined protective and working wire PEN), and the neutral of the power source itself is grounded.

In order to connect the grounding loop of a house or cottage to an electrical panel in this case, you need to redo the grounding system yourself:

In the first option, the PEN wire is divided and connected into two separate buses N and PE, which must be marked. Zero - with blue electrical tape, grounding - with a yellow grounding sign. Bus N must be secured in the shield with special insulators so as not to come into contact with the core. And the PE grounding bus is attached directly to the housing. Both buses are connected to each other by a conductive jumper.

When separating the PEN conductor, under no circumstances should you subsequently connect the N and PE wires - this will lead to a short circuit!

In the second option, the PEN wire is not divided, but is attached to the N bus and is subsequently considered zero. Only the grounding wires of electrical appliances will be attached to the PE bus. This method is preferable, since if the PEN conductor burns out, all users of the power line will be connected to the grounding buses in their houses. And if not all residents have grounding, then this can lead to equipment breakdown for those users who are still concerned about its design.

The only drawback of the TT system is the need to install an RCD or voltage relay, which leads to an increase in the cost of organizing electrical wiring.

How to make grounding - detailed instructions with photos

The grounding device is divided into two stages - installation of ground electrodes and connection of the circuit to the panel. Considering the labor intensity of the process, all work can be divided into two days. The main thing is to wait for dry weather.

Ground loop device

The only requirement for the worker is physical strength, as you will have to swing the sledgehammer well.

It is very important to choose a place for the circuit - in the event of an electrical breakdown, there should be no people or animals above it. The ideal option is to hide the grounding under a fenced flowerbed or asphalt path.
The place for the contour is marked. The most popular scheme is a triangle, as it improves the conductive properties minimum quantity There are three grounding electrodes in the circuit. The optimal distance between them is 1.2 m, but can vary from 1 m to 1.5 m. It is important to maintain the same spacing between the ground electrodes.

Although the contour should be placed no closer than 1 m from the house, the maximum distance should not exceed 10 m.
Following the marking of an isosceles triangle and towards the house, a trench 50-70 cm deep is dug. At the tops, metal corners or pipes are driven in with powerful blows of a sledgehammer to a depth below freezing of the soil (an average of 2-3 m). The heavier the sledgehammer, the faster the work goes. And grounding conductors from copper pipes very convenient to hammer with a regular hammer drill.

The upper ends of the grounding conductors are not hammered in completely, but in such a way that after filling the trench there is another 50 cm of earth above them.
The vertices of the triangle are connected with metal strips or rods. It is very important to weld the joints - this will avoid regular tightening of the bolts when using fasteners. If there is no contact between the grounding conductor and the metal connection, then all the work on constructing the circuit is pointless. (13)

The grounding conductor going to the house is also welded to the circuit. A bolt is welded at the end located on the wall of the house, to which the grounding wire from the busbar in the panel will go.

All welding joints are covered after cooling bitumen mastic in several layers. This will prevent corrosion and resulting loss of contact.
The trench is filled with earth, and part of the grounding conductor located on the surface (the “ground” bus) is painted to protect the metal from moisture. Traditional paint for the grounding conductor is red. But in no case should you paint the entire conductor - it must be in contact with the ground to dissipate the voltage.

Work on connecting the grounding to the panel can be postponed to any other day - if everything is done correctly, the circuit will last 50-70 years without repair, so you need to rush with the connection only if you have electrical appliances already connected to the network.

Correct grounding connection is the key to safety and long service life of equipment

It is very important to correctly connect the ground bus to the panel. For this, copper, aluminum or steel conductors are used. For copper products, the cross-section should not be less than 10 sq.mm, for aluminum - 16 sq.mm, and for steel - 75 sq.mm. Both metal strips and twisted wires can be used.

To attach metal strips, a hole is made along the diameter of the bolt and secured with a nut and washer. The wires should be attached to the bolts with special terminals, and under no circumstances should they be screwed onto them.

The joint must be cleaned to a shine and coated with grease - it protects the metal from oxidation and electrical corrosion.
The grounding conductor is also attached to the panel with a screw connection to the housing. If the switchboard door is not grounded, it is necessary to ground it too - with another conductor. It is important to select in advance the grounding bars in the panel with a sufficient number of holes for different devices - attaching two wires to one point is strictly prohibited.

There is a common misconception that it is better to ground electrical appliances “purely” and not through a common ground loop. But in this case, a large number of “individual” grounding conductors create their own circuit, and in the event of a breakdown of electricity on one device, it is likely that voltage will appear on another.

Grounding check

It is very important not to neglect checking the grounding. Ideally, it should be carried out every few years to make sure that the contacts at the welding site have not moved away. The check is carried out by special measuring instruments, which are not practical to buy for one-time use. Without a special ohmmeter, checking the circuit resistance is useless and even dangerous.

So, when an ordinary light bulb is connected to a phase and circuit, it will light up, even if instead of the circuit a crowbar is stuck into the ground - due to low power consumption. If you use a powerful device, such as a heater, it can be hazardous to your health. In addition, you need to accurately measure the circuit resistance - it should not exceed 4 ohms.

You can use the three-electrode method with an ammeter and a voltmeter, and use a 12-16 volt step-down transformer as a current source, but not everyone has these devices. Therefore, it is better to invite an electrician once and be sure of quality work done!

Operation of modern household and computer equipment without grounding is fraught with its failure. A large part of our country, especially in rural areas, has old-style power transmission systems. They do not provide for protective grounding or are in such a state that they simply do not meet electrical safety requirements. Therefore, owners have to do the grounding of a private house or cottage themselves.

What does it give

Protective grounding is necessary to ensure electrical safety in the home. If done correctly, when a leakage current appears, it leads to immediate tripping of the RCD (damage to the electrical insulation or when live parts are touched). This is the main and main task of this system.

The second function of grounding is to ensure the normal operation of electrical equipment. For some electrical appliances, having a protective wire in the socket (if any) is not enough. A direct connection to the ground bus is required. For this purpose there are usually special clamps on the case. If we talk about household appliances, these are a microwave oven, an oven and a washing machine.

The main task of grounding is to ensure the electrical safety of a private home.

Few people know, but a microwave without a direct connection to the “ground” can emit significant radiation during operation; the reception level of radiation can be life-threatening. In some models, you can see a special terminal on the back wall, although the instructions usually contain only one phrase: “grounding is required” without specifying exactly how it should be done.

When touched wet hands to the body washing machine A tingling sensation is often felt. It is not dangerous, but unpleasant. You can get rid of it by connecting the ground directly to the case. In the case of an oven, the situation is similar. Even if it does not “pinch”, a direct connection is safer, since the wiring inside the installation operates under very harsh conditions.

With computers the situation is even more interesting. By directly connecting the ground wire to the case, you can significantly increase the speed of the Internet and minimize the number of freezes. It’s that simple because of the direct connection to the ground bus.

Do you need grounding in a country house or in a wooden house?

In holiday villages, grounding is mandatory. Especially if the house is built of flammable material - wood or frame. It's about thunderstorms. At dachas there are a lot of elements that attract lightning. These are wells, boreholes, pipelines lying on the surface or buried to a minimum depth. All of these objects attract lightning.

If there is no lightning rod and grounding, a lightning strike is almost equivalent to a fire. There is no fire station nearby, so the fire will spread very quickly. Therefore, in combination with grounding, also make a lightning rod - at least a couple of meter-long rods attached to the ridge and connected to the ground using steel wire.

Grounding systems for a private house

There are six systems in total, but in individual developments, mainly only two are used: TN-S-C and TT. IN recent years TN-S-C system is recommended. In this scheme, the neutral at the substation is solidly grounded, and the equipment has direct contact with the ground. The earth (PE) and neutral/zero (N) are connected to the consumer by one conductor (PEN), and at the entrance to the house they are again divided into two separate ones.

With such a system, a sufficient degree of protection is provided by automatic devices (RCDs are not required). The disadvantage is that if the PEN wire burns out or is damaged in the area between the house and the substation, phase voltage appears on the earth bus in the house, which cannot be turned off by anything. Therefore, the PUE imposes strict requirements on such a line: there must be mandatory mechanical protection of the PEN wire, as well as periodic backup grounding on poles every 200 m or 100 m.

However, many transmission lines in rural areas do not meet these conditions. In this case, the TT system is recommended for use. Also, this scheme should be used in free-standing open outbuildings with an earthen floor. There is a risk of touching the ground and ground at the same time, which can be dangerous with a TN-S-C system.

The difference is that the “ground” wire to the panel comes from the individual ground loop, and not from transformer substation, as in the previous diagram. Such a system is resistant to damage to the protective wire, but requires the mandatory installation of an RCD. Without them, there is no protection against electric shock. Therefore, the PUE defines it only as a backup if the existing line does not meet the requirements of the TN-S-C system.

Grounding device for a private house

Some older power lines have no protective ground at all. They all must change, but when this will happen is an open question. If this is your case, you need to make a separate circuit. There are two options - do the grounding in a private house or country house yourself, with your own hands, or entrust the implementation to a campaign. The services of the campaigns are expensive, but there is an important advantage: if during operation problems arise due to improper functioning of the grounding system, the company that carried out the installation will compensate for the damage (must be specified in the contract, read carefully). In case independent execution everything is on you.

The grounding system of a private house consists of:

grounding pins,
metal strips combining them into one system;
lines from the ground loop to .

What to make grounding conductors from

A metal rod with a diameter of 16 mm or more can be used as pins. Moreover, you cannot take the reinforcement: its surface is hardened, which changes the distribution of current. Also, the hardened layer in the ground breaks down faster. The second option is a metal corner with 50 mm shelves. These materials are good because they can be driven into soft soil with a sledgehammer. To make it easier to do this, one end is sharpened, and a platform is welded to the other, which is easier to hit.

Sometimes metal pipes are used, one edge of which is flattened (welded) into a cone. Holes are drilled in their lower part (about half a meter from the edge). When the soil dries out, the distribution of the leakage current deteriorates significantly, and a saline solution can be poured into such rods, restoring the functioning of the grounding. The disadvantage of this method is that you have to dig/drill holes under each rod—it won’t be possible to hammer them in with a sledgehammer to the required depth.

Pin driving depth

The grounding pins should go into the ground below the freezing depth by at least 60-100 cm. In regions with dry summers, it is desirable that the pins be at least partially in moist soil. Therefore, corners or rods 2-3 m long are mainly used. Such dimensions provide a sufficient area of contact with the ground, creating normal conditions for the dispersion of leakage currents.

What not to do

The job of protective grounding is to dissipate leakage currents over a large area. This happens due to the close contact of metal grounding conductors - pins and strips - with the ground. That's why Grounding elements are never painted. This greatly reduces the current conductivity between the metal and the ground, making the protection ineffective. Corrosion in welding areas can be prevented with anti-corrosion compounds, but not with paint.

The second important point: grounding must have low resistance, and for this good contact is very important. It is provided by welding. All joints are welded, and the quality of the seam must be high, without cracks, cavities and other defects. Please note again: Grounding in a private house cannot be done on threaded connections. Over time, the metal oxidizes, breaks down, the resistance increases many times, the protection deteriorates or does not work at all.

It is very unwise to use pipelines or other metal structures located in the ground. For some time, such grounding works in a private house. But over time, the pipe joints become oxidized and destroyed due to electrochemical corrosion, activated by leakage currents, and the grounding becomes inoperative, as does the pipeline. Therefore, it is better not to use these types of grounding conductors.

How to do it right

First, let's look at the shape of the ground electrode. The most popular is in the form of an equilateral triangle with pins hammered into the vertices. There is also a linear arrangement (the same three pieces, only in a line) and in the form of a contour - the pins are driven around the house in increments of about 1 meter (for houses with an area of more than 100 sq. m). The pins are connected to each other by metal strips - metal bonding.

Procedure

From the edge of the house to the installation site, the pin must be at least 1.5 meters. In the selected area, they dig a trench in the form of an equilateral triangle with a side of 3 m. The depth of the trench is 70 cm, the width is 50-60 cm - so that it is convenient to cook. One of the peaks, usually located closer to the house, is connected to the house by a trench with a depth of at least 50 cm.

At the vertices of the triangle, pins are hammered (a round rod or corner 3 m long). About 10 cm is left above the bottom of the pit. Please note that the ground electrode is not brought to the surface of the earth. It is located 50-60 cm below ground level.

A metal bond—a strip of 40*4 mm—is welded to the protruding parts of the rods/angles. The created ground electrode is connected to the house with a metal strip (40*4 mm) or a round conductor (cross section 10-16 mm2). The strip with the created metal triangle is also welded. When everything is ready, the welding areas are cleaned of slag and coated with an anti-corrosion compound (not paint).

After checking the ground resistance (in general case it should not exceed 4 Ohms), the trenches are covered with earth. There should be no large stones or construction debris in the ground; the earth is compacted layer by layer.

At the entrance to the house, a bolt is welded to the metal strip from the ground electrode, to which a copper conductor in insulation is attached (traditionally the color of the ground wires is yellow with a green stripe) with a core cross-section of at least 4 mm 2.

Grounding outlet near the wall of the house with a bolt welded at the end

In the electrical panel, the grounding is connected to a special bus. Moreover, only on a special platform, polished to a shine and lubricated with grease. From this bus, the “ground” is connected to each line that is distributed throughout the house. Moreover, wiring the “ground” with a separate conductor according to the PUE is unacceptable - only as part of a common cable. This means that if you have two-wire wiring, you will have to completely change it.

Why you can’t make separate groundings

Rewiring the entire house is, of course, time-consuming and expensive, but if you want to operate modern electrical appliances and household appliances without problems, it is necessary. Separately grounding certain outlets is ineffective and even dangerous. And here's why. The presence of two or more such devices sooner or later leads to the output of the equipment plugged into these sockets. The thing is that the resistance of the circuits depends on the condition of the soil in each specific place. In some situation, a potential difference occurs between two grounding devices, which leads to equipment failure or electrical injury.

Modular pin system

All the previously described devices - made from hammered corners, pipes and rods - are called traditional. Their disadvantage is the large volume of excavation work and the large area that is required when installing a ground electrode. This is because a certain area of contact between the pins and the ground is required, sufficient to ensure normal “spreading” of the current. The need for welding can also cause difficulty - there is no other way to connect the grounding elements. But the advantage of this system is relatively low costs. If you do traditional grounding in a private house with your own hands, it will cost a maximum of $100. This is if you buy all the metal and pay for welding, and do the rest of the work yourself

Modular pin (pin) systems emerged a few years ago. This is a set of pins that are driven to a depth of up to 40 m. That is, you get a very long grounding rod that goes to a depth. The pin fragments are connected to each other using special clamps, which not only fix them, but also provide a high-quality electrical connection.

The advantage of modular grounding is the small area and less work required. A small pit with sides 60*60 cm and a depth of 70 cm, a trench connecting the ground electrode to the house is required. The pins are long and thin, drive them into suitable soil not difficult. This is where we come to the main disadvantage: the depth is great, and if you encounter, for example, a stone on the way, you will have to start over. But removing the rods is a problem. They are not welded, but whether the clamp will hold up or not is a question.

The second disadvantage is the high price. Together with installation, such grounding will cost you $300-500. Self-installation problematic, since driving these rods with a sledgehammer will not work. We need a special pneumatic tool, which we have learned to replace with a hammer drill with impact mode. It is also necessary to check the resistance after each driven rod. But if you don't want to deal with welding and excavation, modular grounding pins are a good option.

Grounding is a mandatory element of electrical wiring in a private home. It is grounding that ensures the safety of using electrical appliances and protects you from the risk of electric shock.

A large part of our country (especially in rural areas) has an old-style power transmission system. The presence of protective grounding is not provided for in them, or they are in such a state that they simply do not meet electrical safety requirements. Therefore, owners of private houses have to do the grounding themselves.

Is grounding necessary in a private house?

When the insulation of the supply wire breaks down, a potential appears on the metal body of an ungrounded device. If you touch such a device, you may receive an electric shock. IN best case scenario You will “pinch” a little, and at worst, you will receive serious injuries incompatible with life.

Why does a person get stressed? Current follows the path of least resistance. And it tends to the ground, since it has a large electrical capacity. Therefore, when in contact with a faulty device, your body (having a resistance of about 1 kOhm) becomes the only conductor.

But what if we “offer” the current an easier path by connecting the equipment frame to ground with a metal conductor of lower resistance? In this case, most of the charge will go along it.

stabilize the operation of electrical installations;
protect devices from power surges;
reduce network interference as well as the intensity electromagnetic radiation increased frequency.

Important: All consumers operating from networks with voltages exceeding 42 V AC and 110 V DC must be grounded.

How is grounding different from a lightning rod?

Many people mistakenly confuse 220V and 380V grounding in a private house with a lightning rod or, more correctly, a lightning rod. In fact, there is a difference. Grounding is done so that excess electricity generated in the electrical network goes into the ground without overloading electrical circuits. A lightning rod also conducts atmospheric electrical charge into the ground. But the grounding loop always works, but the lightning rod only works when lightning strikes it.

If you need to install a lightning rod in a private house with your own hands, then you should not load its functions with a regular ground loop. Why? Because the lightning rod must conduct the charge of atmospheric electricity into the ground so that it does not pass through the house. Otherwise, the conductor or its attachments may become very hot, which in turn may cause a fire.

When installing a grounding loop, it is worth considering that the current in it is much less than from lightning. In addition, installation of the circuit involves a two-way process: the current flows not only to the neutral core, but also from it.

That is, if you install 220V and 380V grounding in a private house with your own hands and combine it with the functions of a lightning rod, then the lightning charge may not completely go into the ground, but return to the internal network. This may result in network overload, failure of electrical appliances, or fire.

So is it possible to combine a grounding loop and a lightning rod? Yes, if you use specialized factory-made circuits for this. They will allow you to combine two functions, but the cost of such a circuit will be higher than that of two independent devices.

Grounding device in a private house

The ground loop is a device consisting of two subsystems: internal and external. The two routes are connected in the distribution panel. The second part is located outdoors and consists of electrodes that are connected by metal plates and dug into the ground.

A metal bus is drawn from such a device, which is connected to the main panel. The operating principle of the design is such that when a person comes into contact with electrical equipment, the current flows into the soil not through the body, but through a special conductor.

In this case, you can do different types Do-it-yourself grounding in a private house. 380v requires a slightly different approach. A person has a resistance value of 1 kOhm, and a mechanism has a resistance value of 4 Ohms. Electric current takes the fastest and easiest path to ground, which has lower resistance.

A grounding electrode is an element that is in contact with the ground and produces the discharge and distribution of current. In private buildings they are used natural views devices made of steel pipeline, protective coating power cable and reinforced concrete part of the foundation or column.
The grounding conductor is a part that connects electrical installation and ground electrode.

Three vertical elements are used, as well as three horizontal stripes that connect the vertical elements. The steel strip is used as a conductor between the distribution board and the ground loop.

A closed circuit is made in the form of a triangle.
Linear is made of series-connected jumpers.

A contour in the form of an isosceles triangle is popular. It is located at a distance of several meters from the foundation of the building. In this case, a trench is dug into which steel elements are driven. Then a steel strip is installed around the perimeter.

In general, ground loops can be in the form of a triangle, rectangle, oval, line or arc. The best option for a private home is a triangle, but others are also quite suitable.

Triangle

Grounding in a private house or country house is most often done with a contour in the form of an isosceles triangle. Why is this so? Because with such a structure, in a minimum area we obtain a maximum area for current dissipation. The costs of installing a grounding loop are minimal, and the parameters correspond to the standards.

The minimum distance between the pins in the ground loop triangle is their length, the maximum is twice the length. For example, if you drive the pins to a depth of 2.5 meters, then the distance between them should be 2.5-5.0 m. In this case, when measuring the resistance of the ground loop, you will get normal values.

During work, it is not always possible to make the triangle strictly isosceles - stones come across in the right place or other difficult-to-pass areas of soil. In this case, you can move the pins.

Linear ground loop

The disadvantage of this method is that to obtain the required parameters, a larger number of vertical electrodes is required. Since hammering them in is still a pleasure, if there is a meta, they try to make a triangular outline.

Ground loop elements

three vertical grounding rods that are driven into the ground; they can be made in the form of a corner;
three horizontal steel strips that connect vertical grounding conductors;
a steel strip that acts as a conductor between the ground loop and the distribution board.

Reinforcement cannot be used for the grounding loop, since its surface quickly oxidizes and does not allow even distribution electric current.

Typically, the grounding loop is made in the form of an isosceles triangle, which is located at a distance of 1-3 m from the foundation of the house. It is at this distance that a trench about a meter deep is dug into which the horizontal contour elements are laid. Vertical steel elements are driven in to a depth of about 3 m so that approximately 20 cm remains on the surface.

Then a steel strip is welded along the perimeter of the contour, which connects the vertical pins. The steel grounding conductor is bolted to the switchboard housing. How to make grounding loops in a private home more efficient?

To do this, the junction of the core and the ground loop must be thoroughly cleaned. Another option is to lay a steel strip with a cross-sectional area of at least 16 mm² from the distribution board to the circuit.

Another option for increasing grounding efficiency is to replace the steel core with a flat steel strip. Due to the larger area of contact with the ground, its current conductivity is also higher. However, it is more difficult to lay a steel strip in the ground than a core; it has to be laid in the ground in pieces, and then welded together. In this case, exclusively the welding method is used.

If you have read or heard how to make proper grounding in private homes, then you probably know that using bolts to connect structural elements can lead to very negative consequences. The fact is that the bolts oxidize quite quickly, which is why the circuit stops conducting electricity. For the same reasons, you cannot paint the frame of the circuit, since the paint stops the current from passing into the ground.

If the installation of a grounding loop cannot be done without the use of bolts, then they must be located above the ground surface, be securely tightened and thoroughly cleaned. From time to time, the bolts should be lubricated with a special conductive lubricant.

What is the difference between grounding and grounding

Many people mistakenly confuse these two terms, although there is a very big difference between them. Zeroing is intended for use on industrial enterprises, but most developers neglect this rule by installing grounding contours in residential buildings. This is not entirely safe and is done either due to a lack of knowledge or due to a desire to save money.

If a three-wire cable (zero, ground, phase) is installed in a single-phase electrical wiring system, and a five-wire cable is installed in a three-phase system (three phases instead of one), then this is absolutely grounding without grounding.

It is important to remember that nulling is calculated only on the probability short circuit and does not perform grounding functions. This feature is very useful when using industrial equipment, but is completely useless in everyday conditions, quite the opposite. For example, if a neutral wire is connected to an electrical appliance, then if it burns out or if you accidentally confuse the zero with a phase, the equipment can easily burn out.

If you nevertheless decide to install grounding together with a grounding kit for a private home, then it is highly recommended to additionally install protective equipment. For example, voltage limiters and protective shutdown devices are very popular.

Ground loop material

The grounding loop consists of vertical and horizontal grounding conductors.

corrugated fittings;
round steel with a diameter of less than 10mm.

What can be made from:

round steel 14 mm or more (with a smaller diameter it is difficult to drive an electrode into the ground);
steel corner with dimensions of at least 40*40*5.

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

Tools

Having completed the calculation and selected the grounding loop diagram, you can proceed to purchasing materials.

rods from black steel with a diameter of 16 millimeters or more - vertical electrodes;
steel strip (bus) with a cross section of 5×40 millimeters - horizontal grounding conductor;
copper wire with a cross-section of at least 10 square millimeters - connecting the circuit to the distribution board;
bolts with a diameter of 10 mm;
black exterior paint or mastic.

Important: Building reinforcement is not suitable for use as ground rods. The fact is that the outer layer of such rods is hardened, so the electric current is distributed unevenly across the cross section. And this, in turn, leads to the destruction of the metal. In addition, the reinforcement is susceptible to corrosion.

The quantity and dimensions of materials are selected in accordance with the calculated data.

shovel (soil development);
welding machine (connection of circuit elements);
grinder (trimming materials);
pliers (bend horizontal strip);
a sledgehammer and a hammer drill, preferably with a special attachment for rods (for driving vertical electrodes).

All pins of the circuit are connected to each other by metal bonding.

copper wire with a cross section of less than 10 mm2;
aluminum wire with a cross-section of at least 16 mm2;
steel conductor with a cross-section of at least 100 mm2 (usually a strip of 25 * 5 mm).

Most often, the pins are connected to each other using a steel strip. It is welded to the corners or heads of the rod. It is very important that the quality of the weld is high - this determines whether your grounding will pass the test or not (whether it will meet the requirements - resistance less than 4 ohms).

When using aluminum or copper wire, a large cross-section bolt is welded to the pins, and the wires are already attached to it. The wire can be screwed onto a bolt and pressed with a washer and nut, or the wire can be terminated with a connector of a suitable size. The main task is the same - to ensure good contact. Therefore, do not forget to strip the bolt and wire to bare metal (can be treated with sandpaper) and tighten well - for good contact.

Do-it-yourself grounding loop in a private house

From the edge of the blind area of the house to the installation site of the pin there must be at least 1.5 meters. In the selected area, they dig a trench in the form of an equilateral triangle with a side of 3 m. The depth of the trench is 70 cm, the width is 50-60 cm - so that it is convenient to cook. One of the peaks, usually located closer to the house, is connected to the house by a trench having a depth of at least 50 cm.

A metal bond - a strip of 40 * 4 mm - is welded to the protruding parts of the rods/angles. The created ground electrode is connected to the house with a metal strip (40*4 mm) or a round conductor (cross-section 10-16 mm2). The strip with the created metal triangle is also welded. When everything is ready, the welding areas are cleaned of slag and coated with an anti-corrosion compound (not paint).

After checking the grounding resistance (in general, it should not exceed 4 Ohms), the trenches are covered with earth. There should be no large stones or construction debris in the ground; the earth is compacted layer by layer.

Grounding circuit of the PUE norms

In the electrical panel, the grounding is connected to a special bus. Moreover, only on a special platform, polished to a shine and lubricated with grease. From this bus, the “ground” is connected to each line that is distributed throughout the house. Moreover, the “ground” is a separate conductor along PUE standards unacceptable - only as part of a common cable. This means that if you have two-wire wiring, you will have to completely change it.

Grounding installation

First, we prepare the vertical grounding conductors. We cut them using a grinder in accordance with the calculated data. Then we grind the ends of the pins into a cone. This is done so that the electrode enters the ground more easily.
Then we cut the steel strip. The length of each segment should be slightly larger than the side of the triangle (about 20–30 centimeters). It is advisable to bend the ends of the strips with pliers in advance for tight contact with the pins during welding.
We take the prepared pins and hammer them into the vertices of the triangle. If the ground is sandy and the electrodes go in easily, then you can get by with a sledgehammer. But if the soil density is high or stones are often encountered, then you will have to use a powerful hammer drill or even drill wells. We drive the rods so that they protrude above the base of the trench by about 20-30 centimeters.
Next, we take a metal strip 40x5 millimeters and weld it to the pins. As a result, you will have a contour in the form of an equilateral triangle.
Now we draw the contour to the building. We also use a stripe for this. It needs to be taken out and fixed against the wall (if possible, near the switchboard).

Test work for functionality

After execution, a mandatory check is performed. To do this, a light bulb is connected to one end of the circuit. The contour is made correctly if the lamp shines brightly. The performance is also checked using a factory device - a multimeter.

Why you can’t make separate groundings

The thing is that the resistance of the circuits depends on the condition of the soil in each specific place. In some situation, a potential difference occurs between two grounding devices, which leads to equipment failure or electrical injury.

As a rule, power supply in private homes is carried out by overhead lines with a TN-C grounding system. In such a system, the neutral of the power source is grounded, and the phase wire L and a combined neutral protective and working wire PEN are connected to the house.

After the house has installed its own grounding loop, it is necessary to connect it to the electrical installations of the house.

convert the TN-C system to the TN-C-S grounding system;
connect the house to the ground loop using the TT system.

Connecting the house to the ground loop using the TN-C-S system

As you know, the TN-C grounding system does not provide a separate protective conductor, so in the house we are converting the TN-C system to TN-C-S. This is done by dividing the combined neutral working and protective PEN conductor into two separate ones, working N and protective PE.

And so, two power wires approach your house, phase L and combined PEN. To get a three-wire electrical wiring in the house with separate phase, neutral and protective wires, it is necessary to correctly divide the TN-C system into TN-C-S in the incoming electrical panel of the house.

To do this, install a bus in the shield that is metallic connected to the shield; this will be a PE grounding bus; a PEN conductor will be connected to it from the power source side. Next, from the PE bus there is a jumper to the bus of the zero working conductor N; the bus of the zero working conductor must be isolated from the shield. Well, you connect the phase wire to a separate bus, which is also isolated from the switchboard.

After all this, it is necessary to connect the electrical panel to the grounding circuit of the house. This is done using copper stranded wire, connect one end of the wire to the electrical panel, attach the other end to the grounding conductor using a bolt at the end, which was specially welded for this purpose.

Connecting the house to the ground loop using the TT system

For such a connection, it is not necessary to make any separations of the PEN conductor. Connect the phase wire to a bus isolated from the switchboard. You connect the combined PEN conductor of the power source to a bus that is isolated from the switchboard and in the future consider the PEN to be simply a neutral wire. Then connect the shield housing to the house ground loop.

As can be seen from the diagram, the ground loop of the house has no electrical connection with PEN conductor. Connecting the ground in this way has several advantages compared to connecting using the TN-C-S system.

If the PEN conductor burns out on the power source side, all consumers will be connected to your ground. And this is fraught with many negative consequences. And so your grounding will not have a connection with the PEN conductor, this guarantees zero potential on the body of your electrical appliances.

It often happens that on the neutral conductor, due to an uneven load across the phases (phase imbalance), a voltage appears that can reach values from 5 to 40 V. And when there is a connection between the network neutral and the protective conductor, it can also occur on the housings of your equipment little potential arises.
Of course, if such a situation arises, the RCD should trip, but why rely on the RCD. It would be better and more correct not to tempt fate and not lead to such a situation.

From the considered methods of connecting the grounding loop of a house, we can conclude that the TT system in a private house is safer compared to the TN-C-S system. The disadvantage of using a CT grounding system is that it is expensive. That is, when using a TT system, the following must be installed: protective devices like , voltage relay.

I would also like to note that it is not necessary to make the outline in the form of a triangle. Everything depends on external conditions. You can place horizontal grounding conductors in any order, around a circle or along one line. The main thing is that their number is sufficient to ensure minimal grounding resistance.

Ready-made grounding kits for a private home

Despite the fact that purchasing and installing a grounding loop yourself is cheaper, home craftsmen are increasingly purchasing ready-made grounding kits for a summer house or private home. Their installation is simpler and therefore faster.

However, buying grounding for a private home, the price of which is higher than the material from which it is made, is not acceptable for everyone. Let's try to summarize the average prices for such kits in Russia as of January 2018:

This is approximately how prices for products are distributed on Russian market. However, buying ready-made kits is half the battle. You also need to mount the circuit. Average cost installation work for grounding a private house varies from 10,000 to 20,000 rubles. depending on the region.

In general, the cost for the safety of relatives living in the house is not so high. Therefore, it is not worth saving on grounding. If you only purchase the material (angle, tires), the price for grounding a private house can increase significantly and you should not forget about this.

10 Ohm is a popular domestic manufacturer that offers grounding kits for installation at various depths. Installation depth varies from 6 to 30 m, and prices range from 6,000 to 25,000 rubles;
ZandZ – universal grounding electrodes in the form of one or more electrodes prefabricated type from stainless steel. Mounted to a depth of up to 10 m, the price depends on the number of electrodes, installation depth and other parameters. Average cost installation kit for 5 m – 23,000 rubles;
Galmar is another popular manufacturer of prefabricated grounding electrodes. Installation is possible to a depth of up to 30 m; such a kit will cost 42,000 rubles;
Elmast – grounding kits from a domestic manufacturer. They are made of stainless steel, supplied unassembled, and can be mounted at different depths. Characterized by a long service life. Distinctive feature These grounding conductors are highly resistant to aggressive chemical environments and adverse natural influences. Average price for a kit for installation at a 6-meter depth - 9,000 rubles;
Ezetek are relatively inexpensive kits with average performance characteristics. The advantageous advantage of the kit for installation to a depth of 6 m is the price of 6,000 rubles.

There are many other manufacturers offering both ready-made kits for grounding a private home, as well as individual components. You should only trust trusted companies in this matter.

Many owners of private houses are familiar with the problem of old and dilapidated wiring, which can be very difficult to ground. The only correct option in this case is to completely replace the old wiring with a new one. However, not everyone can afford it, so sometimes you have to make do with what you have.

If it is not possible to replace all the wiring, then you need to at least install new switches and junction boxes. In this case, there is no need to change their arrangement. When installing new sockets, a very important point is monitoring the grounding wires. They must be located in distribution boxes and go to the ground bus through the distribution board. Its mount is mounted on the shield body.

Another relatively simple and cheap option for how to properly ground in private homes is to completely disconnect the old wiring. In this case, it is simply disconnected from the panel and remains in the wall, and new wiring is laid outside. Plastic covers work well for this purpose, and new switches and sockets can be installed in existing holes in the walls.

To update distribution boxes, it will be enough just to remove the old wires from them.

cable channels to protect external wiring;
wires;
sockets, switches and distribution boxes.

If you need to install new wiring in an old house and conduct it to electrical equipment grounding, you will also have to install a new distribution board. In this case, you can leave the old wiring, but only low-power electrical appliances should be connected to it.

A major overhaul of electrical wiring in an old house is long and expensive; a more budget-friendly option to protect yourself from fire and the possibility of a short circuit is to supplement the electrical wiring with one grounding wire. You don’t even need to lay it inside the wall, but simply lay it in a plastic cable channel.

The advantages of this option are obvious: the cable channel fits perfectly into any interior and attaches well to any material. The channel is usually carried out between distribution boxes, as well as from the distribution board. In each, all grounding wires must be connected to each other and go to the grounding bus.

How to properly ground in a private home

Metal elements may become corroded, which will increase the resistance of the material.
When soil moisture is high, it is necessary to use devices and elements with galvanic coating.
It is not recommended to install the circuit near pipelines where the soil can warm up.
It is better to connect the electrodes by welding.
There must be a distance between the electrodes that exceeds their length.
Elements must be located below the freezing depth.
The resistance of the entire system should not exceed 4 ohms.

More recently protective grounding was equipped only at industrial enterprises and other facilities where powerful electrical installations are used. To protect their workers from accidental breakdown to the housing, each installation and device was necessarily grounded. But time does not stand still. Today our homes are crammed with powerful household appliances: refrigerators, freezers, microwave ovens, induction cookers, "warm floor" systems and much more. But all this is the source increased danger. If their isolation is violated, “close communication” with powerful devices can be fatal. That is why, in order to protect all inhabitants of the home, country houses Electrical grounding must be provided. Its arrangement can be entrusted to professionals, or you can do it yourself.

Why is protective grounding necessary?

The professional literature states that protective grounding is the connection of non-current-carrying parts of electrical installations with the ground (soil), which is carried out deliberately. At the same time, in in good condition These parts of electrical appliances and installations are not live. But if a partial destruction of the insulating layer suddenly occurs, metal case the device may be live.

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

Protective grounding is performed in order to divert current to the ground (ground). In this case, it is extremely important to make a grounding loop with such low resistance that the current, which is distributed in inversely proportional relation between the person and the grounding device, passes through the person at the maximum permissible norms, and most of it is redirected to the ground.

What is a ground loop?

The most common type of ground loop is electrodes buried in the ground, connected to each other in some kind of loop, which can be any geometric figure- triangle, square or other, 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 area that can be used for the circuit. Sometimes a ground loop is made around the perimeter of the building. The resulting structure is attached to the shield, for which a grounding cable is used.

The distance from the grounding loop to the house should not be too large; 4–6 m is considered optimal. The loop should not be located closer than 1 m to the house, and it is undesirable to place it further than 10 m.

Important! The grounding circuit must be installed below the soil freezing level, 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 are 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 install another version of the grounding system.

Ground loop made of black rolled metal

Any ferrous metal rods can be used as grounding electrodes. This can be a steel angle (most often used), a pipe, an I-beam, or fittings with a smooth structure. The principle of choice is simple - ease 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 experimentally or made calculations, but the most common is a triangular grounding circuit with electrodes at the vertices of the triangle. The rods are connected to each other by metal strips, the same strip leads to the distribution panel.

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

Important! Before grounding your home, consult with regular electricians in your area. Ask them what designs are most often installed and with what characteristics in your region. At what depth to place the electrodes, how far away from the house, what distance between the rods should be made. This will make your task much easier.

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

The set includes rods made of high quality steel, they are coated 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 connected to each other using brass couplings. To deepen the rods into the ground there are tips that are screwed onto 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 is used to treat all elements of the system.

Ready-made modular grounding systems have several significant advantages:

By connection vertical elements it is possible to carry out a depth of 50 m;
The rods are not very susceptible to corrosion due to copper plating and stainless steel;
No welding required;
Arrangement can save space, because... the entire system can be equipped on 1 m2;
No special equipment is required for installation;
Durable.

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

How to calculate grounding

For those who do not like unnecessary complications, there is an option to perform grounding experimentally. You can arrange a triangular outline on 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 circuit resistance. The grounding requirements are as follows: the resistance of the ground loop must be in the range from 4 to 10 ohms. A general rule- how less value resistance, the better. If the measurement result of our circuit does not meet the requirements, then we add more electrodes and connect them with the already installed ones. We take measurements again. And we repeat this until our circuit has a resistance of 4 ohms.

More the right decision will still make all the necessary calculations before installing the circuit. The most important thing is to determine the number of electrodes required 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 using the formula:

The value of the seasonal climatic 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 using the formula:

We find the resistance to spreading horizon. ground electrode:

We find the length of the ground electrode using the following formulas:

Final number of electrodes:

The demand coefficient can be found in the table:

The utilization factor indicator indicates the influence of currents on each other, which depends on the location of the vertical grounding conductors. At parallel connection electrodes, the currents passing through them influence 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 apart from each other at a distance equal to their length, for example, 3 m.

The value of the number of electrodes obtained during the calculations is rounded up to a whole number. The calculations are ready, you can begin installation.

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

It is recommended to begin grounding installation in the warm season. Firstly, it’s easier to produce earthworks. Secondly, the value of soil resistance will be more accurate and maximum. This is very important for quality grounding. Otherwise, you can make grounding when the soil is temporarily saturated with water, and its resistance will be 4 Ohms, and then a drought will occur 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 grounding loop made of rolled metal in the form of a triangle:

First of all, choose a convenient place. We dig a trench in the shape of a triangle. The optimal depth is from 0.7 to 1 m, width 0.5 - 0.7 m. The length of each line is as we determined during the calculations (length of the horizontal ground electrode).
From one of the corners (any) we dig a trench leading to a power panel near the house.
Vertical grounding electrodes are driven into the vertices of the triangle. You can use a 50*50 steel angle or any other rolled metal rod. For ease of driving into the ground, we sharpen the end of the rod with a grinder. If the soil is too hard to drive 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 (minimum 40*5 mm) to the rods so that a triangle is formed. We lead one lane along the trench to the power cabinet.
IN private house We establish grounding through the shield. To do this, we connect the strip to the ground wire or directly to the power panel with a 10 mm bolt. We must weld the bolt to the strip.

The next step is checking the grounding. To do this, you will need an Ohmmeter device, which costs a lot. In order to check the resistance once or twice in your entire life, it is expensive to buy it. Therefore, we invite specialists from energy management to check the circuit resistance. In addition to taking measurements, they will also fill out a grounding loop passport. If the resistance indicators correspond to the norm, then you can bury the circuit. If not, then we drive in additional electrodes.
We fill the trench. For this purpose, we use homogeneous soil without admixtures 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, the neutral is also grounded. At the entrance to the building, the neutral is connected to re-grounding. The fact is that electricity comes to private homes by air. For power line supports 6 - 10 kW it is carried out re-grounding neutral, but for power lines of 0.4 kW - energy 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 advisable that all neighboring ones 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 your own hands, well, go for it. Just remember - your creation is designed to protect the whole family.