Modular grounding. Installation of grounding for a home Is one grounding pin in the ground enough?

Or a country house always involves a large amount of electrical work. In this range of tasks, along with supplying power to the house, installing distribution and protective equipment When laying internal lines, a well-planned and executed grounding system is no less important. Unfortunately, when carrying out “self-construction”, inexperienced owners quite often forget about this point or even deliberately ignore it, trying to achieve some kind of false economy Money and labor costs.

Meanwhile, the grounding system is of extreme importance - it can prevent many troubles that can lead to very sad or even tragic consequences. According to existing rules, electrical network specialists will not connect the house to the power line if this system is not in the house or if it does not meet the necessary requirements. And the owner, one way or another, will have to decide the question of how to make grounding at the dacha.

IN modern houses urban development, a grounding loop is necessarily provided at the design stage of the building and its internal communications. The owner of a private home will have to decide this issue himself - invite specialists or try to do everything himself. There is no need to be afraid - all this is a completely doable task.

Why is a ground loop needed?

To understand the importance of grounding, it is enough basic concepts from school course physics.

The vast majority of private houses are powered from a single-phase network alternating current 220 volt . The electrical circuit necessary for the operation of all devices or installations is provided by the presence of two conductors - actually, a phase and a neutral wire.

Design of all electrical appliances, tools, household and other equipment provides insulation elements and protective devices that should prevent voltage from entering conductive housings or casings. However, the possibility of such a phenomenon can never be excluded - the insulation may be discharged, burn out from unreliable, sparking contacts in wire connections, circuit elements may fail, etc. In this case, phase voltage may get to the device body, touching which becomes extremely dangerous for humans.

Situations are especially dangerous if there are people near such a faulty device. metal objects, having so-called natural grounding - heating risers, water pipes or gas pipes, open reinforcement elements of building structures and etc.. At the slightest touch to them the chain can close and be fatal dangerous current will pass through the human body towards a lower potential. Such situations are no less dangerous if a person is standing barefoot or in wet shoes. wet floor or ground - there are also all the prerequisites for closing the alternating current circuit from the device body.

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

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

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

Some owners are prejudiced that for grounding it is enough to use water supply or heating pipes. This is extremely dangerous and absolutely unreliable. Firstly, it is impossible to guarantee effective voltage removal - the pipes may be heavily oxidized and may not have good enough contact with the ground, and in addition, they are often subject to plastic areas. Electric shock cannot be ruled out if someone touches them in the event of a breakdown of the power supply to the housing, and neighbors may also be exposed to such a danger.

Most modern electrical appliances are immediately equipped with a power cable with a three-pin plug. The corresponding sockets must be installed when carrying out wiring installation work in the house. (Some older model electrical appliances have a contact terminal on the body for a ground connection instead.)

There is a strictly defined color “pinout” of the 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 so, knowing this, some “wise” owners, wanting to save on updating the wiring and organizing full grounding, simply make jumpers in the sockets between the neutral contact and the grounding. However, this does not solve the problem, but rather aggravates it. Under certain conditions, for example, in the event of a burnout or poor contact of the working zero in some part of the circuit, or in the event of an accidental phase change, a phase potential will appear on the body of the devices, 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 that has been said is that grounding is mandatory. structural element home electrical network. It immediately performs the following functions:

• Effectively removes 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 heating pipes, water supply, gas supply.
• Ensuring everything works correctly installed systems and safety 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 the induction of voltage onto the housing of the system units. Any discharge can lead to failure of electronic components, malfunctions, and loss of information.

Now that the importance of the grounding system has been explained, we can move on to the question of how to do it yourself in a private home.

Prices for protective automation

Protective automation

What are the types of grounding systems in private homes?

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

Soil type	soil resistivity (Ohm × m)
Sand (at level groundwater below 5 m)	1000
Sand (at groundwater level above 5 m)	500
Fertile soil (chernozem)	200
Wet sandy loam	150
Semi-solid or forest-like loam	100
Chalk layer or semi-hard clay	60
Graphite shales, clayey marl	50
Plastic loam	30
Plastic clay or peat	20
Underground aquifers	from 5 to 50

It is obvious that 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 can be solved in several ways - from increasing the installation depth of pin electrodes, to increasing their number, the distance between them, or total area contact with the ground. In practice, several basic schemes are most often used:

• Scheme “a” - installation of a recessed metal closed loop around the perimeter of the house. As an option - shallowly driven pins connected in a ring by a bus.

IN dacha construction it is used infrequently due to its large volume 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 recessed pin electrodes connected by one busbar - this design is easy to make yourself, even in a limited space.
• Diagram “c” shows grounding with one electrode installed at a greater depth. Sometimes such a system is even installed in the basement of a building. The scheme is convenient, but not always feasible - it is almost impossible to implement on rocky soils. In addition, for such a grounding system, you need to use special electrodes - we will talk about it below.
• Scheme “d” is quite convenient, but only if it was thought out at the stage of designing the house, and executed during the pouring of the foundation. It would be extremely unprofitable to implement it on a finished building.

So, the easiest way to implement it is with minimal costs schemes “b” or, if possible, “c”.

Grounding using homemade metal parts

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

Schematically, this system looks like this:

Location buried electrodes are selected so that it is as convenient as possible to bring the grounding bus to the distribution panel. Optimal distance from the house - 3-6 meters. Acceptable limits are no closer than one meter and no further than ten.

The dimensions indicated in 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 slightly 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 greater depth, you can increase their number.

A good idea is to contact your local utility company in advance for recommendations on how to install a ground loop. These specialists probably have well-thought-out schemes that have been tested 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 ones with a wall thickness of at least 3.5 mm. You can take a steel strip with an area cross section about 48 mm² (12 × 4), but it is more difficult to drive vertically into the ground. If you decide to use a steel rod, then that It’s better to take galvanized one with a diameter of at least 10 mm.

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

• So, initially markings are made at the selected location.

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

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

• Electrodes of the required length are prepared. 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 and unpainted.

• At the designated locations, the electrodes are driven into the ground using a sledgehammer or electric hammer. They are buried 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 busbar (horizontal grounding conductor) made of a 40 × 4 mm metal strip. Only welding is applicable here, although you can find recommendations to use a bolted connection. No, in order to ensure reliable and durable grounding, this harness must be welded - a threaded contact placed underground will quickly oxidize, and the circuit resistance will increase sharply.

• Now you can lay a bus from the same strip to the foundation of the house. The tire is welded into one of the clogged electrodes and placed in a trench, then it goes onto the base of the building.
• The busbar is attached to the base. 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 linear expansion of the metal during temperature changes. A bolt with M10 thread is welded at the end of the strip. A copper terminal with a grounding wire will be attached to it, which will go to the distribution panel.

• 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 used 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 connections.

• 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 indoors and will be less susceptible to oxidation under the influence of high humidity air.

Bronze Distribution Plate for Ground Wires

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

You should not rush to immediately fill the mounted circuit with soil.

— It is recommended, firstly, to capture it in a photograph with reference to surrounding stationary ground objects - this may be required to make changes to project documentation, as well as for carrying 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 resort to tricks by generously watering the areas around the corners hammered into the ground with a saturated solution of ordinary table salt. This will certainly improve the performance, however, do not forget that salt activates metal corrosion.

By the way, if it is not possible to hammer in the corners, then they resort to drilling wells to the required depth. After installing the electrodes, they are filled with clay soil as densely as possible, which is also mixed with salt.

After the functionality of the ground loop has been checked, 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 filled with soil. It must be homogeneous, not littered and free of crushed stone inclusions. Then the backfill area is carefully compacted.

Video: installation of a grounding loop using a metal corner

Using ready-made factory kits

Ready-made factory-made kits are very convenient for organizing grounding at the dacha. 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 of stainless steel. The diameter of the pieces may differ in different sets - from 14 to 18 mm.

• To connect them, they are equipped with threaded couplings, and for ease of penetration through the ground, a steel tip is included in the kit.

In some kits, the couplings are not threaded, but press-fit. In this case, one end of the ground pin is tapered by forging and has a ribbed surface. When impacted, a strong connection occurs and a reliable electrical contact between the rods.

• For transmission shock impact a special attachment (dowel) made of high-strength steel is provided, which will not be deformed by the impact of the hammer.

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

• Some kits include 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 driven in sequentially and incrementally to the required depth.

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

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

Video: manually driving pin electrodes

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Components for lightning protection and grounding

What type of rod coating should I choose – galvanized or copper-plated?

• From an economical point of view, galvanizing with a thin layer (from 5 to 30 microns) is more profitable. These pins are not afraid of mechanical damage during installation, even when left deep scratches 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 up” 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 reacting, protects the iron it covers, which is more active from a chemical point of view. Such electrodes can serve for a very long time without compromising efficiency; for example, the manufacturer guarantees their safety in loamy soil for up to 100 years. But during installation, care should be taken - in places where the copper plating layer is damaged, a corrosion area will likely appear. To reduce the likelihood of this, the copper plating layer is made quite thick, up to 200 microns, so such pins are much more expensive than conventional galvanized ones.

What are the general advantages of such a set of grounding systems with one deeply placed electrode:

• Installation is not particularly difficult. No extensive excavation work is required, no welding machine is needed - everything is done with ordinary tools that are found in every home.
• The system is very compact; it can be placed in a tiny space or even in the basement of a house.
• If copper-plated electrodes are used, then the service life of such grounding will be several tens of years.
• Thanks to good contact with the ground, minimal electrical resistance is achieved. In addition, the efficiency of the system is practically not affected seasonal conditions. The level of soil freezing accounts for no more than 10% of the length of the electrode, and winter temperatures cannot in any way negatively affect the conductivity.

There are, of course, some 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 some will be put off by the price of the kit. However, this is a question With with porno, since high-quality rolled metal for a conventional grounding circuit is also not cheap. If we also add the duration of operation, simplicity and speed of installation, and the absence of the need for specialized tools, then it is quite possible that this approach to solving the grounding problem may seem even more promising from the point of view of efficiency.

Video: how to ground your home using a modular pin system

This is a drawn steel rod with a diameter of 14 mm and a length of 1.5 meters, coated by electrolytic deposition (electrolysis) with copper of 99.9% purity, forming a coating with a molecular and inextricable bond with the steel.

Threads are applied along the edges using the knurling method for their mutual connection using a coupling.

In addition to electrical conductivity, high-quality steel in such a grounding device also plays a mechanical role necessary for burying the electrode in the soil. The pins have a high tensile strength (600 N/mm²) and can be driven into the ground with a jackhammer to a great depth - up to 40 meters.

Thickness copper plating is at least 0.25 mm along the entire length of the rod (including threads). This guarantees its (coating) resistance to bending, peeling, and scratching during installation. This is especially important on threads, where a thinner layer of copper will be completely destroyed from loads and friction with the coupling during penetration (installation) *.

These features guarantee high corrosion resistance of the ground pin and provide such long term service (up to 100 years).

* Features of creating threads
The “correct” thread is applied AFTER copper plating - by knurling, because Only this method makes it possible to achieve high overall quality of the pin.

An alternative “technology” for copper plating of pins: with already formed threads (before applying the coating) is cheaper, BUT it shows a worse (and dangerous during operation) result.
This is due to a feature of electrolysis: thickening of the coating in the recesses/cavities, due to which the base material (steel) on the thread can only be coated with a thin (0.03 - 0.05 mm) layer of copper.
Such a thin coating is easily damaged during installation by impacts and friction in the coupling. Subsequently, when the grounding electrode is used with such violations, pockets of electrochemical corrosion (“copper-iron”) appear, leading to its complete destruction within 2-3 years.

Copper plating technology

The key factor making a high-quality grounding pin involves creating a strong, uniform copper coating on a steel workpiece required thickness with minimal impurities.

On a separate page "Copper-plated steel" are presented detailed description main characteristics, manufacturing processes and tests of the coating.

Comparison with galvanized pins

From 1910 to 1955, The National Institute of Standards and Technology (NIST) conducted an extensive study of underground corrosion, during which 36,500 samples representing 333 types of ferrous and non-ferrous metal coatings and protective materials were tested. in 128 locations throughout the United States*. This study is rightfully considered one of the most full research corrosion that has ever been carried out.

One of the results of this study was the fact that a ground pin coated with 254 microns of copper retains its specifications for over 40 years in most soil types. And rod electrodes coated with 99.06 microns of zinc in the same soils can retain their qualities only for 10-15 years.

In addition, the protection period zinc coverage decreases in proportion to the increase in the amount metal structures in the soil located next to the electrodes (the more structures there are, the less the coating lasts / the faster it “disappears”). Examples of these structures can be: reinforcement of building foundations, pipes, etc.

Grounding pin with copper coating 254 microns thick, extracted from soil (loam) after 10 years

Grounding rod with zinc coating 99 microns thick, extracted from soil (loam) after 10 years

Another study of the corrosion properties of copper coating was carried out by the Polish company GALMAR. Artificial aging samples under conditions simulating aggressive soil (an “acidic” swamp), showed that a grounding pin with a 250 micron copper coating retains the necessary technical characteristics for at least 30 years.

Modern Appliances and the equipment requires 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 house - a triangle, but others are 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 that? 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 get caught in in the right place or other difficult-to-pass ground areas. 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 greater than the length of the electrodes themselves.

With a linear circuit, a larger number of vertical electrodes is necessary so that the dissipation area is sufficient

The disadvantage of this method is that to obtain the necessary parameters it is necessary large quantity vertical electrodes. 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. For this it is necessary to provide good contact grounding conductors with soil. The problem is that grounding 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 of 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 bottom part flattened into a cone, 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 with a cross section of 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 of a suitable size. The main task is the same - 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 approximately 20-30 cm longer than the calculated length - 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 hammering 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 24*4 mm steel strip, 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 the transition from a metal tire to copper wire(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 grounding 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 to the earth bus with separate wires (inextricable) - heating, water supply, foundation reinforcement frame, sewerage, gas pipeline (if they are made of metal pipes). Therefore, the grounding bus must be taken “with a reserve”.

For PEN separation conductor and creating 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 “seats” .

The metal “ground” bus must be attached to metal case 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.

One of the options for installing a grounding loop in a private house is to install a pin grounding. In this case, the operating time is significantly reduced, while the functionality of the ground electrode is not inferior to similar system options (linear, electrolytic, etc.). In this article we will tell you how to make modular-pin grounding with your own hands and what are the advantages of such a system.

Design features

What is such a system and what does it consist of? The device consists of steel one and a half meter pins, which are processed with copper and connected using couplings. The kit also includes a brass clamp that connects the horizontal and vertical contours. Below is a diagram of the design.

The modular pin grounding system is installed as follows: a landing pad (nozzle) is mounted on the top of the pin, which in turn is connected to the coupling. The attachment is necessary to transmit the force of the vibrating hammer. A steel tip is installed on the lower part of the structure. It makes it easier to drive the unit into the ground. There are several types of tips, the scope of which depends on the hardness of the soil.

In addition, the kit comes with a special electrically conductive liquid paste, the purpose of which is to protect against corrosion and constantly maintain electrical resistance during operation. Electrically conductive paste is applied to all threaded connections of the structure. You can also use a special waterproof anti-corrosion duct tape. It is resistant to acids, salts and gases, and does not allow moisture to pass through.

Installation stages

Modular-pin grounding is installed according to simple principle. First of all, the tip is put on the first pin. But before installation, it should be treated with electrically conductive paste against corrosion. We screw the coupling onto the other end and also treat it with anti-corrosion paste. The landing pad is then screwed onto the device to apply the forces of the vibratory hammer.

We place the assembled modular-pin grounding in a pre-prepared hole in the ground. You need to screw it into the ground as deeply as possible with your own hands. Then you need to connect the vibrating hammer to the network and place it on the rod site. Thus, the pin is immersed in the ground along its entire length. You only need to leave 20 cm in order to connect another rod.

This is followed by . To do this, you need to remove the landing nozzle and connect it to the place where it was located. special device, ohmmeter, as in the photo below:

When the first rod is located in the ground along its entire length, the landing attachment for the vibratory hammer is removed and another pin is mounted through the coupling. A special clamp that holds the pin in vertical position, rises along installed device up. And the connecting coupling and attachment for the vibrating hammer are again installed on the mounted structure, after which the process is repeated.

Spread resistance should be checked after installing each vertical rod. The pins are installed until the required resistance is established. The figure below shows a diagram of the change in resistance depending on the length:

Next, you need to connect the horizontal ground electrode and the vertical conductor. To do this, a brass clamp is attached to the end of the rod that protrudes from the ground and a horizontal ground electrode is connected to it. A special plate is placed between the pin and the horizontal cable, which protects against corrosion when dissimilar metals come into contact. After the system has been connected, the connection points are treated with special adhesive tape. It serves as additional protection against corrosion.

Advantages and disadvantages of the system

Modular-pin grounding, like any system, has its pros and cons. Compared to the classic and standard circuit, pin grounding has the following advantages:

• ease and simplicity of installation;
• occupies a small area;
• installation is carried out minimum quantity workers (1–2 people);
• installation occurs without welding work, since all connections are made using couplings;
• thanks to the vibratory hammer, there is no heavy earthwork;
• modular pin grounding is resistant to corrosion, as it is treated with special lubricants and coatings, thanks to which they last for several decades;
• regardless of the ground, the pin system is easily driven into the ground;
• structural elements are manufactured industrially, due to which they are of high quality and are ready for immediate installation without additional preparatory work.

Modular pin grounding has one significant disadvantage - its high cost. But, despite this drawback, the system is beneficial if you take into account all its advantages.

The industry produces a wide variety of kits that combine elements that are necessary for reliable and high-quality installation. Modular-pin grounding has an important purpose - it protects the house from fire, and people in the room from electric shock.

Modular grounding ZANDZ
(pr. Russia) is intended for installation of grounding devices (grounding conductors) at residential facilities (house, dacha), at telecommunications and energy facilities of mobile and mobile operators landline connection, at industrial enterprises.

Such a ground electrode is a prefabricated structure consisting of steel pins 1.5 meters long connected together, coated with a layer of copper.

Advantages of modular grounding

Advantage of modular pin design:

• ease of installation of the electrode to a depth of up to 30 meters, without the use of specialized equipment and tools. All operations are carried out by 1 person. The large depth allows for very effective grounding.


• minimum area occupied by the grounding electrode makes it possible to install such grounding in the basements of buildings, or in the vicinity of the walls of the house in the form of just one point. Compactness minimizes required excavation work.


• all parts are mated without welding *

Superiority industrial production elements are:

• excellent resistance of all parts to corrosion, which is expressed in the service life of the ground electrode up to 100 years.


• complete resistance of the copper coating of the pins to mechanical damage(for example, bending and peeling) during installation, which allows installation in soils with the presence of gravel or small construction debris
  (through the use of electrolytic copper deposition technology on steel).

* The connection of elements of grounding devices NOT made of ferrous metals is permitted by technical circular 11/2006 of the RosElectroMontazh association (link to document)

Grounding kits

To construct grounding devices with the necessary characteristics (for example, to achieve the required grounding resistance), various ready-made ZANDZ modular grounding kits (pr. Russia) are used, which contain everything necessary for installing a grounding electrode.

All components are easily interfaced with each other.

Available in five varieties ready-made kits, differing in the total length of the pins, main purpose and configuration:

ZZ-000-015 -	universal ground electrode for installation in the form of a prefabricated electrode: one 15 m deep or three 5 m deep (4.5 + 4.5 + 6 m). Used as a grounding conductor with low spreading resistance and a grounding conductor for lightning protection of an object.
ZZ-000-030 -	universal ground electrode for installation in the form of a prefabricated electrode: one 30 m deep or three 10 m deep (10.5 + 10.5 + 9 m). Used as a grounding conductor with very low spreading resistance and a grounding conductor for lightning protection of an object.
ZZ-000-045 -	multi-electrode grounding system in the form of 15 prefabricated electrodes 3 m deep. Used as a distributed grounding switch with low touch voltage.
ZZ-000-424 -	(4 prefabricated electrodes 6 m each).
ZZ-000-636 -	grounding conductor for installation on container communication or power supply facilities (6 prefabricated electrodes 6 m each).

Traditional ground electrode
(set ZZ-000-045)

A large number of vertical electrodes installed at a shallow depth

Special ground electrode
(sets ZZ-000-424
and ZZ-000-636)

Grounding installation for container facilities

Equipment

Individual configuration

Accessories

The brass coupling is designed to connect the pins to each other. It is made in such a way that the pins touch each other in the very center of the coupling and the driving energy required to bury the pins in the soil is not transferred to the coupling. In this way, the shock impulse does not “dissipate” and also removes the mechanical load from the coupling.

The pointed steel tip makes it easy to drive the pins into hard ground.

Profiled stainless steel clamp with M10 bolts. Allows you to connect a copper-plated pin to a grounding conductor - a round wire or strip (up to 40 mm wide).

It is possible to safely use steel and galvanized conductors - for this purpose, there is a gasket inside the clamp that prevents the formation of an electrochemical bond between steel/zinc and copper.

To prevent self-unscrewing threaded connections"bolt-nut" uses spring washers (Grover washers / Grover washers) installed between the clamp surface and the nut.

Used to reduce electrical resistance between pins and coupling, as well as additional protection ends of the pins (in the coupling) from corrosion. Lubricant is also used for the guide head, making it easier to remove after inserting the next pin. During installation, lubricant is applied to the threads of the parts.

The tape is used to protect the connection of the pin with the grounding conductor from soil and electrochemical corrosion by completely displacing water (moisture) from the connection point, without which the corrosion process is impossible. At the same time, the tape does not lose its physical and mechanical properties for many years.

Made from non-woven synthetic fibrous material, impregnated and coated with a neutral composition based on saturated petroleum hydrocarbon (petrolatum) and an inert silicon-containing filler. Remains plastic under a wide range of temperatures. Does not harden or crack. Highly resistant to inorganic acids, alkalis, salts and microorganisms, highly sealed against water, water vapor and gas.

This tape only protects the terminals for connecting the conductor.

A steel nozzle with a hardened striker transmits the force of the jackhammer to the guide head (to the mounted pins). Adapted for use with jackhammers seat SDS-Max.

Additional items

Grounding conductor (PV-1 25 mm²)

Single-core, stranded and stranded copper conductor with a cross-section from 4 to 185 mm² in PVC insulation is used to connect the ground electrode to the object (GZSh in the shield).

The conductor is supplied by the meter and in ready-made coils of 3/5/10 meters
(ZZ-500-103 / ZZ-500-105 / ZZ-500-110), crimped at one end with a tip with a hole for a D8 bolt for connection to the GZSh in the shield.