How to make grounding yourself in the country. How to make grounding in the country? Ground loop. Device in a private house of the TN-C-S grounding system
On the suburban area often used different electrical engineering: tools, machine tools, electric mowers and more. The danger of electric shock is great, and therefore a grounding device in the country is vital. Protective earth will divert voltages to earth if the wiring insulation is damaged. We suggest that you study the recommendations for organizing grounding in the country: this will help you do the installation on your own.
The ground loop can be divided into two parts: external and internal. The latter consists of:
- grounding conductors of electrical wiring;
- grounding terminals in sockets;
- terminal block in the electrical panel, which unites all the grounding conductors of the electrical wiring cables.
General grounding scheme
The internal system is connected in the switchboard with the external one by means of a screw connection to the busbar, which is part of the external system. In turn, the external (street) system combines electrodes buried in the ground, connecting them metal parts and the tire itself.
Grounding prevents electric shock in case of insulation failure
Protective earth installation
A grounding organization scheme in the country should be selected from the three most commonly used.
- Closed: electrodes buried in the ground are connected by jumpers so that an oval, rectangular or triangular contour is formed. The advantage of such a scheme is reliability: if one of the jumpers is damaged, the ground will perform its function.
- Linear: all electrodes are dug in one row. In this case, the probability of system failure is high if the first jumpers are damaged.
- Pin: one long electrode using special technology is driven into the ground to a great depth. The disadvantage is the high cost of materials.
Installation of pin grounding
Tip: out of the three options presented above, it is recommended to mount grounding in the country house with your own hands in a closed system.
Ground Loop Mounting Technology
The following tool is needed for grounding in the country:
- bayonet shovel - for digging a trench;
- grinder - for the manufacture of parts;
- sledgehammer - for driving electrodes into the ground;
- welding inverter - for connecting electrodes with jumpers and a bus;
- adjustable wrench - for tightening the nut in the switchboard (when connecting the internal and external grounding systems.
Instructions for organizing grounding in the country house involves the use of the following materials:
- steel corner 50 × 50 mm, 5 mm thick - three pieces of 2 m each (can be replaced with a pipe, fittings or channel with the same cross-sectional area);
- three steel tires 0.12 m long (width 50 mm, thickness 5 mm);
- steel bus length from the installation site of the ground loop to the wall of the cottage;
- copper wire, insulated, with a cross section of 6 mm² or more (depending on the cross section of the phase wire);
- M10 bolt with washer, engraver and nut.
Tip: for mounting a protective ground loop, it is better to use electrodes and tires made of of stainless steel. Such a system will last longer than made of carbon steel.
The step-by-step process of grounding installation can be represented as follows.
Choosing a place for grounding
- The ground loop should be as far away as possible from a place that people often visit. In the event of damage to the insulation of the electrical wire, the protective circuit will operate, and it can be dangerous near the electrodes of the circuit.
- It is recommended to mount the circuit along the fence (for a linear scheme), in the front garden.
- If possible, the area where the ground loop is located is fenced off.
Linear scheme: electrodes are arranged in one row along the fence
Excavation
- It is necessary to mark the triangle in the area selected for installation work.
- Setting aside the required distances with the help of a tape measure, we drive pegs into the ground and pull the cord between them.
- With the help of a cord, we also mark the segment between one of the electrodes and the wall of the house.
- With a shovel, we dig a trench with a depth of 0.5 - 0.7 m.
Trench with ground loop
Installation of external and internal grounding system
The sequence of actions is as follows.
- At the vertices of the triangle, we drive the electrodes into the ground with a sledgehammer until about 50 mm remains on the surface - for attaching the jumpers.
- We weld segments of tires to the tops of the electrodes so that a triangle forms.
- In the trench leading to the wall of the cottage, we lay the tire, one end of which is welded to the contour, and the other is brought to the wall (to a height of at least 0.5 m). Near the foundation, it is required to leave a margin to compensate for ground movements.
- We weld an M10 bolt on the wall at the top of the tire.
- We attach the cable laid from the electrical panel to the bolt. Fastening is carried out using a washer and an engraver, pressed with a nut.
- We fill the trench with soil and compact it. It is recommended to pour water: this helps to improve the contact of the metal with the ground.
All parts are welded together
Important: electrodes and tires must not be painted. Metal treatment with a rust converter is allowed. In order to make it easier to drive the electrodes into the ground, we make their tops sharp.
The junction of the internal and external system can be placed in the mounting box
Installation check
Proper grounding for a summer residence should have a resistance of no more than 10 ohms. Compliance with this condition is checked using an ISZ instrument (ground resistance meter) or a megohmmeter.
In the absence of devices, you can use an incandescent bulb: we attach to one of its contacts phase wire, and to the other - a wire connected to ground. The brightness of the light bulb should not differ from its usual (when connected to a 220 V network). Otherwise, all connections of the parts of the circuit must be checked and redone in order to improve contact.
Earth resistance measurementmegger
At the end of the article on how to install grounding in the country - a video with expert explanations.
Many people prefer to spend their summers in country house. This is a great option to take a break from the bustle of the city, grow your own vegetables and fruits. But this article will not be about gardening, but about safety. If during the construction of high-rise buildings the developer necessarily provides for grounding, then private sector must take care of himself. Let's talk about how to make grounding in the country with your own hands. The scheme and the connection process - this is what attention will be focused on.
What is grounding and why is it necessary?
Electric current can be compared with water in only one property. Both liquid and electricity flow along the path of least resistance. Today we are almost completely dependent on the availability of electricity. Almost everything is on it. Appliances, ranging from TV and ending with heating equipment.
Each of these devices has fuses and insulation, which is designed to protect the consumer from Imagine what could happen if a layer insulating material will break. That's right, you can get electrocuted. It is good if an automatic machine is installed that will de-energize the equipment in time. If not, then the consequences can be dire. To prevent anything like this from happening, they install grounding in the country with their own hands, the scheme of which may be different, but the essence is the same.
What is the ideal ground?
This question can be answered unequivocally: the one that has the least resistance. We have already figured out that the current will go where there is less resistance. In our case, it is necessary to achieve the smallest possible value. Note that the human body also has its own resistance. It changes depending on climatic conditions and the human condition. For example, the resistance of a person in an intoxicated state is negligible, which is why it is always harder for a drunk person to survive after a strong electric shock.
In our case, we will stick to the value of 4 ohms. In this case, the grounding resistance should be slightly less than this figure. In any case, it is desirable to find out such information in the PUE. Well, now let's go directly to the topic.
What is the importance of soil?
Many may say that there is no difference where and to what depth to dig in the ground, and they will be absolutely wrong. Type and other factors are of paramount importance. But in any case, there is general rule. It lies in the fact that more land saturated with water, the deeper it is necessary to drive the electrodes. You also need to reduce their step.
And now about the type of soil. It also has its value in terms of resistance. For example, peat - 20 Ohm * m, black soil and clay - 25-30 Ohm * m, sandy loam - 150 Ohm * m. Sand is also worth mentioning, the resistance of which reaches from 500 to 1000 Ohm * m. This parameter increases depending on the depth ground water. As you can see, do-it-yourself grounding in the country, the diagram of which will be discussed a little lower, is not so easy to do correctly.
All about electrodes
The first thing to decide is the depth of the electrodes. It is recommended not to bury them deeper than 3 meters, but less than 1.5 meters from the surface is also impossible. Much depends on how deep the water is. If it is 2.5 meters, then it will be enough for you to drive the electrodes to a depth of no more than 2 meters.
The grounding scheme at the dacha (mounted by oneself) implies a certain step (distance) between the electrodes. It usually makes sense to keep a distance of 1.2-3 meters. As for the number of electrodes in the circuit, there should be at least three of them. Arrangement form - in a row or a triangle. The distance from the contour to the foundation of the building is at least 3 meters. In any case, it is advisable to seek help from electricians. Let installation work you do it yourself, but it still doesn’t hurt to learn about the type of soil and the depth of water from professionals. In addition, a do-it-yourself grounding scheme in the country house can be drawn up, since there are currently plenty of options for the sample. Well, now let's move on.
We make grounding in the country with our own hands: diagram, photo
In this section, we will talk about the circuits used for grounding. The most common scheme is a triangle with electrodes at the vertices. In this case, it is necessary to understand that the entire contour must be at the same depth (below the freezing of the soil).
A separate matter is the connection of the circuit. By themselves, the electrodes dug into the ground do not carry any load. Before the grounding is completely ready, they must be interconnected. For this, fittings are suitable as a last resort.
As for the type of connection, welding should be a priority, moreover, it is necessary to use just such a method of connecting the electrodes to each other. From one electrode to the power cabinet ( switch box) a steel strip is carried out. As electrodes, you can use a section of 4 x 4 mm, fittings 12 x 12 mm, steel pipe with a wall thickness of at least 3.5 mm or steel strip 12 x 4 mm. In general, this, as well as a shovel and a crowbar, should be quite enough to equip a full-fledged grounding.
About the material and cross section of the electrodes
We can safely say that it is necessary to build on the section of the material. But you need to understand that important role it also plays whether you can drive the selected electrode into the ground. For example, you can give preference to a steel rod sharpened at the base and it doesn’t matter if it is a profile pipe or an I-beam. If you took a corner, then it can be cut with a grinder. This will turn out a sharp wedge, which is very convenient to drive into the ground. But as for the reinforcement, corrugation is unacceptable here due to a decrease in soil resistance.
If you have the opportunity to purchase a ready-made grounding kit, then do so. It is a set of copper-plated electrodes one meter long. The structure is connected with threaded connections. It is very convenient, and installation is carried out as quickly as possible, however, the price of such a kit is rather big. By the way, it doesn’t matter at all, do-it-yourself grounding is done in the country for gas boiler or microwave oven, since the steel strip is connected to the power cabinet. Therefore, all equipment will be grounded.
to give their own hands: step by step instructions
Now is the time to start earthworks. We have already decided on the material of the electrodes and the depth of their occurrence. Now you need to choose appropriate place. The priority is to dig a trench no further than 10 meters from the shield. First of all, we dig a trench half a meter wide and a meter deep in the form of an equilateral triangle. From it we make a trench to the power cabinet. If the density and type of soil allow, then we drive in the electrodes at the vertices of the triangle. Otherwise, small wells will have to be drilled.
It is noteworthy that if we drilled wells, then the recess can be covered with soil, mixing it with salt. This will significantly reduce the resistance, but the corrosion process will proceed more actively. After installation, the electrodes should rise slightly above the ground so that they can be welded. Please note that doing grounding in the country with your own hands without welding is unacceptable. After welding work will be completed and we will receive closed triangle, we lead the strip to the power cabinet. There we fasten it with a 10 mm bolt and weld it to the strip.
Verification work
After you have completed all the above steps, you need to check the resistance of the circuit. For this we need an ohmmeter. In this case, it is desirable to involve a specialist from the energy department. He will do necessary measurements, if the grounding in the country house, the diagram of which was given a little higher, was done correctly, it will draw up the necessary documentation.
If we have achieved a resistance of less than 4 ohms, then excellent, if not, we expand our circuit with the help of additional electrodes. If everything is in order, then we fall asleep trenches. At the same time, the use of construction debris and any other waste is unacceptable. You need to fill it with homogeneous soil.
It is important
Please note that many experts recommend filling the circuit with water, thereby reducing its resistance. Often this is done before the arrival of an employee from the energy department, so that there are no problems with the documentation. But we tried not for the sake of printing on paper, but for our own safety, do not forget about it.
If you live in a rocky area, then the vertical arrangement of the electrodes will not suit you. In this case, it is advisable to use horizontal or radial types of electrodes. A step of 3 to 10 meters is required, and the electrodes should be arranged in the form of divergent beams or a grid.
Conclusion
Another great way out is grounding in the country on pile foundation. In this case, you do not need to dig a trench and clog the electrodes. It is enough to make a competent contour of piles. But you need to understand that in this case, the likelihood of electrochemical corrosion increases. Consequently, the piles will last an order of magnitude less than they could. But in terms of reliability perfect solution from any side.
In general, we figured out how to make grounding with our own hands. There is nothing particularly difficult, the most important thing is to be careful at all stages, take into account the depth of soil freezing, the level of groundwater and others. important parameters. In any case, if you do everything right, you will be satisfied. The risk of electric shock from household appliances will be minimized.
The time has come when we can hardly imagine life without modern household appliances. " Smart House provides our lives with everything we need. Electronic systems with minimal human intervention, and supply us with necessary information. All these gadgets are not cheap at all and just imagine what a disaster a short circuit can turn into! To prevent this from happening, grounding is necessary. This material will discuss how to make grounding in a private house with your own hands. 220V is the standard mains voltage, and we will discuss in detail how to make sure that it does not harm either people or household appliances.
Read in the article
Information for those who still do not know what grounding is for
Why is grounding necessary? It is difficult to find a person who does not know what electricity is. The first negative experience from contact with him was received by many in childhood, putting their little fingers in. Remember those invigorating sensations? The thing is that the human body is 70 percent liquid, and, as you know, it conducts electricity very well. And if you conduct a powerful stream of electricity through this organism, the tissues will collapse.
It is sometimes surprising how adults get into unpleasant situations with electricity, knowing these basics perfectly.
Important! If you accidentally find yourself near a broken wire of a high-voltage power line, leave the danger zone by jumping on one foot. As soon as you put two feet on the ground, you will inevitably get an electric shock.
By the way, professional electricians, more than once beaten by this very current, they use not only an insulated tool and special gloves, but also dielectric shoes. It does not allow the chain to close.
Someone may say: well, I don’t go under power towers, I’m under my own, I’m safe. No, they say, there is no such need for grounding for a private house. And it will be wrong. Just in the house, the insidious 220 volts are just waiting for you to relax. A simple example: you installed a modern one and connected it to a . Everything is wonderful for the time being, until the heater suddenly failed and hit its body. Well, if an adult decides to feel the batteries, he has a small chance of surviving. What if it's a child?
Here, in order to avoid such catastrophic consequences, grounding is necessary in the country, in the house, in the apartment, in the office.
Grounding and grounding: what is the difference and is there one?
Grounding is metal frame(contour), which is the link between electrical network houses and land.
How does grounding work? The circuit is buried in the ground near the house and connected to the house's electrical network using conductors. Three wires are suitable for each home: phase, zero and ground. Modern manufacturers electrical equipment (shields, sockets) no longer produce models without grounding.
It was used in old-style power networks - this is when the "ground" contacts were brought out to the shield and connected directly to zero. And it turned out that zero was also grounding at the same time.
Important! There are such kulibins who, when installing new sockets with grounding, install a jumper between ground and zero and believe that they have taken care of safety in this way. But in fact, if the zero conductor accidentally breaks, then there will be no grounding. From such an outlet in open wiring, for example, in log house there will definitely be a fire.
Zeroing is considered less efficient system safety than grounding. Why? In the switchboard with such a system there is an automatic machine that works in the event of a short circuit. It is set to a certain critical current. If it “breaks through” less, for example, not 18, but 10 amperes, the automation simply will not work. But a person from such a blow may well receive serious injuries.
Thus, we can conclude that grounding and lightning protection in private homes is the best choice. But for an apartment in an apartment building, you should choose zeroing.
How to make grounding in a private house, taking into account the standards
When planning the arrangement of grounding, you should first understand the terminology. Basic concepts you need to know:
- Ground conductor- this is a wire with maximum conductivity, connecting the device (electricity consumer) to the ground electrode.
- grounding conductor- a frame made of a corrosion-resistant material that conducts current well, buried in the ground.
Important! For effective work the grounding conductor must be buried in the soil half a meter below the freezing level and below the drying level in areas with a hot climate. Ground rods must always be in moist soil.
In the process of studying the issue, you may come across the term "land". Under it, all the constituent parts of the grounding structure are usually combined.
Ground loops in a private house, arrangement requirements:
- when installing the structure, mechanical drilling of the soil is not used, you will have to dig a hole;
- a steel angle 3 meters long is used as a ground electrode;
- the design will require 3-4 corners. They should be fastened together with a metal strip using;
- a grounding conductor with a cross section of 6 mm2 or more is connected to the structure, the second end of the conductor.
There are a few more important requirements, and when arranging the contour, you need to perform at least one of them:
- equalize potential values;
- install automation to turn off electricity in an emergency;
- use wiring with reliable double insulation;
- install isolating transformers on different objects Location on.
How to properly make grounding is described in the GOST R 50571.5.54-2013 standard. In particular, this document describes what should not be done during such work. We note only two the most important moments: Do not ground to or leave the ground conductor on a surface without proper moisture protection.
Do-it-yourself grounding of a private house: diagrams and recommendations
Even if it is completely built up, you can always find a place for an outline. It can also be placed in the garden or. The contour is buried in the ground and will not harm the plants.
Do-it-yourself grounding scheme in the country house begins with determining the number of consumers and installing wiring using a grounding conductor in each outlet. The ground bus is placed in a common shield.
The circuit at 220 or 380 volts does not fundamentally differ. The circuit is still the same, there are only nuances in the connection methods.
Important! Terminals cannot be stacked on top of each other. If this is done, resistance will increase during the oxidation process and the consumers following in the circuit will be unprotected.
The ground conductor from the shield to the circuit must be solid. Any twisting or even increases the resistance and reduces the efficiency of the system.
Tires can be connected in a circle, line or triangle. The triangle is traditionally considered the most robust design. Even if one tire is accidentally separated, the circuit will work.
Note! The legislation does not require owners of private houses to install grounding. There is no need to invite certified specialists for this work. The whole structure can be installed by hand.
Requirements for the ground loop in a private house
Remember the school physics course? Current flows in the direction of least resistance. If violate insulating layer in conductive devices, energy will go where the resistance is lower. So in an electrical appliance, breakdowns occur on a metal case. It is not at all necessary that the device will stop working, but its owner will certainly receive a discharge, barely touching the case.
What is a ground loop? To perform its task, it must be made of a material that easily conducts electric current. Great option- copper-plated steel parts, they will last for a long time, as they are slightly susceptible to corrosion.
Why is it best to use a metal corner, and not, for example, pipes? Pipes are also possible, but the corner is easier to hammer into the ground. It is to hammer, since its surface must be in close contact with the ground for effective operation. It is more difficult to hammer a pipe, but if there is no corner at hand, it or even thick smooth reinforcement will do.
Important! The distance of the contour from the house should be at least one, but not more than ten meters.
Making calculations
Calculations for the contour can be done approximately, you just need to know the basics. There are formulas that professionals use, and they need to be applied if your home has some kind of powerful electrical appliances that consume a large number of energy.
Important! When installing the circuit, do not cover it with paint, varnish or other protective composition. This will greatly reduce the efficiency of the system.
R=U/I
Wherein U- voltage (according to the voltmeter), and I- current strength (according to the readings of the ammeter).
There is a formula for the resistance of the rod, with which you can make calculations if there is no ammeter or voltmeter. Estimate how much more difficult it is in this case to calculate how many ohms the ground should be:
The value of ρ in these formulas is resistivity soil. If you know the soil content in the region where the site is located, you can determine this value from the table:
- in dry soil with deep groundwater, use long rods, dry soil has high resistance;
- do not use thin metal for an outline, it will quickly collapse from .
Advice! When in doubt about your calculations, use computer programs"Electrician", "Calculation of grounding devices", "Grounding" or "Shark". They will help not only to calculate the necessary parameters of the grounding structure, but also to organize lightning protection.
An example of calculating grounding for a private house using the Electrician program in the video instruction:
How to make 220 V grounding in a private house with your own hands: step by step
Do-it-yourself grounding device in a private house does not require any special skills and special tools. It will only take a sledgehammer and. We have already said that the ground loop in a private house with our own hands of 380 or 220 volts is not fundamentally different. So we offer you a simple algorithm of actions:
| A photo | Description of works | |
 | Installation of the ground loop begins with drawing up a diagram of the device and determining its location. Optimal distance from the house - 3-5 meters. | |
 | For tires, use a metal angle or smooth steel rods. Reinforcement is not recommended for contour use. It is hardened, and this violates the distribution of current over the cross section. In addition, such rods are very susceptible to corrosion. | |
 | For the contour, it is necessary to dig a trench about 80-100 centimeters deep. The width of the trench does not matter, but keep in mind that you will need to carry it out in the future, so think about how it will be convenient for you. | |
 | The distance between vertical ground electrodes is 1.5 - 2 meters. To facilitate the process of clogging, the rods are sharpened. If corners are used, they are also cut off at the ends so that they easily enter the ground. | In the slotting mode, gradually drive the pins to a depth, leaving about 20-25 centimeters of the rod on the surface of the trench. |
 | When all vertical tires are driven in, weld a metal strip to them. It is not recommended to replace welding bolted connections. During the oxidation process, the contact of the horizontal and vertical ground electrodes will be broken. | |
 | After mounting the horizontal ground electrode, you need to connect it with a conductor to the shields. To do this, large bolts are welded at the end, on which the conductor will be fixed. Welding points can be treated against corrosion special composition, but the contra itself is by no means colored! |
Modern electrical appliances are becoming more powerful, and, accordingly, the risks of damage by them are increasing. The grounding device guarantees not only the safety of people, but also the safety of equipment.
The principle of operation of the grounding device
Electric current, like a liquid, flows from the place of greatest resistance (phase L "+") to the smallest (N zero "-"). In case of damage to the insulation, the electrodes rush to any of the nearest conductors electric current which has the least resistance. Most often, they are metal parts of the body, touching which becomes extremely dangerous.touch to faulty electrical appliances dangerously!
Even if there are automatic devices installed in the PES shield, the probability of electric shock remains: after all, they are designed for a certain amount of current. When grounding, any, even a small charge that has fallen on the case, instantly flows into the ground.
The current outlet conductors (PE) are ground loop: several metal rods acting as electrodes. dug into the ground to a certain depth and connected in a single circuit. In this case, the resistance of the ground loop is selected in such a way that it is less than the electrical resistance of the human body (less than 4 ohms).
Building grounding
Calculation of the ground loop
It is quite difficult to accurately calculate the dimensions of the contour and the depth of its immersion in the ground. For this you need to know:the ability of the soil to prevent the free passage of current (its electrical resistance);
resistance of the metal from which the ground electrodes are made;
their number and the exact depth of their laying in the ground.
In order to avoid complex calculations that only a specialist can do, you can first make a ground loop according to average dimensions, and then using ohmmeter measure its resistance. If it is higher than 4 ohms, the length of the circuit should be increased by increasing the number of metal rods deepened into the ground.
Ground loop
Advice. Since an ohmmeter is a fairly expensive device, you can invite a specialist from the power grid or a similar organization to measure the resistance. In the event that the depth of soil freezing is known exactly (this data can be clarified in geology), the measurement of the resistance of the circuit can be omitted or insured and increase the length of the circuit.
Installation of the ground loop
Any metal with a cross section of 1.5 cm2 or more can be chosen as grounding conductors for the manufacture of the circuit. Most often, a 50 × 50 corner is used, one end of which is cut obliquely by a grinder for better entry into the ground.1. The shape of the contour can be any, while the minimum number of rods buried in the ground is three. That is why the most common is the contour in the form triangle, the sides of which are 1.2-1.5 m or more.
Ground loop
2. To equip the circuit in the ground at a distance of 3-10 m from the building, closer to the switch cabinet, a triangular trench is excavated with equal sides from 0.7 deep and 0.5 m wide. An additional trench is laid leading to the power cabinet.
trench preparation
3. Vertical ground electrodes are driven in at the corners of the circuit, which will act as electrodes. Rods get clogged to the depth of soil freezing(but not less than 1.5 and not more than 3 m) so that they top part protruded 20-25 cm above the ground. For better entry into the ground, their the ends are sharpened. In this case, there is a rule: the more moisture is contained in the soil, the smaller the step of the electrodes and the smaller the depth of their immersion.
Driving metal rods
4. It matters too current resistance. So, if the resistance of clay and chernozem is 25, peat - 20, then sand - as much as 500 Ohm * m and above. The resistance of stony soil is also very high. In rocky terrain, the immersion depth of the pins ceases to have crucial(after all, it is unrealistic to get to wet ground with minimal resistance). In such cases, ground loops should be installed with larger area a frame located horizontally or in the form of divergent rays.
Soil resistivity
5. If the density of the soil is too high and it is difficult to drive the rods into it, you can first drill holes in the ground.
6. To connect the chain to their ends around the entire perimeter of the triangle, strips of steel 40 * 4 mm or smooth reinforcement 14 mm are welded. Welding area should be treated to reduce corrosion bitumen or other anti-corrosion compound.
Welding circuit circuit
Important! The use of corrugated reinforcement for tying the contour is not recommended. Otherwise, voids may disrupt contact with the ground.
7. Such a circuit is welded to the ground wire using bolt 10 mm. The use of twist for connection is unacceptable.
Twisting to connect the chain is not allowed
After checking the loop resistance data with an ohmmeter, the trench is covered with soil.
Naturally, all internal wiring in the house is mounted three-wire circuit, where the third is the ground wire. They are brought to the electrical panel, and then connected to a common ground loop. As additional protection the system is equipped RCD or difavtomatami.
3-wire circuit
Lightning protection device
The voltage of lightning discharges that occur between electrified clouds can reach billions of volts. Natural lightning rods are trees that are deeply rooted in the ground (after all, damp earth has minimal resistance). Sometimes lightning can strike even the highest parts of buildings. That is why lightning protection is most often installed on the roof.The lightning rod is a conductor made of metal 1.5 m in diameter from 12 mm, installed at the highest point of the building. On too large buildings, there may be several. The higher they are located, the larger the territory they protect. At the same time, their maximum height can be 15 m (with a higher height, their effectiveness decreases).
Lightning rod device
Important! Metal, coated with varnish or paint, cannot serve as a lightning rod.
If the metal receiver tube is hollow, it must be welded. Aluminum or copper wire, which is attached to such a receiver with couplings or terminals. Its other end goes to the ground electrode, arranged according to the same principle as the circuit intended for grounding buildings, described above.
Important! To enhance protection, the grounding of the lightning rod is necessarily connected using a steel strip passing underground to the ground loop of the building.
Construction is a labor-intensive and very costly process. Therefore, having invested in the construction of a house or other structure, do not forget about grounding. You can make your own grounding. It is made to protect household appliances and appliances from power surges.
The essence of grounding work is to protect a person in case of violation of integrity. The current flows from phase to zero, and if this network is damaged, the current rushes to the conductor with the least resistance. As a rule, these are metal parts of the device case, touching which can lead to disastrous consequences. Therefore, in the presence of grounding, the charge goes into the ground.
The contour acts as a current collector. You can make a ground loop with your own hands, just connect three electrodes into a circuit and bury them in the ground to the desired depth. Loop resistance should be no more than 4 ohms.
- Ground resistance;
- Conductor material resistance;
- Conductor size;
- Depth of installation of a contour.
Since these calculations are difficult to make, and sometimes only a professional can do it, you can go the most in a simple way. To do this, you need to make the design of the ground loop standard size. Three conductors, as a rule, are a metal corner with a cross section of 1.5 cm and a size of 50x50 mm, 2-3 meters long, connected with a horizontal tape. The tape is made of steel 40x4mm. The distance between vertical conductors should be 1.2 m. A current conductor made of round steel is supplied to this structure. When everything is assembled, it is necessary to measure the resistance, if it exceeds 4 ohms, then there are 2 options for reducing the resistance:
- increase in the length of the electrodes;
- increasing the number of electrodes in this closed circuit.
Ground Loop Installation
The circuit must be placed underground, therefore, for easier entry into the ground, the lower end of the vertical ground electrodes is cut at an angle. The ground loop usually has the shape of a triangle, therefore, at a distance of at least 3 meters from the building, a triangular trench is prepared with dimensions: depth 70 cm, width 50 cm. From this triangle, a trench is laid to the switch cabinet. Vertical ground electrodes are hammered into the vertices of the prepared triangle to the extent of soil freezing from 1.5 m to 3 m. above the soil (inside the trench) a segment of 20-25 cm in size should protrude.
Tip: with dense soil, it is allowed to prepare holes for mounting electrodes in advance.
When the electrodes are installed, a horizontal ground electrode is welded to the ends of the electrodes that remain above the ground. Joints should be treated with anti-corrosion agents. Further, a ground wire is welded to this structure using a 10mm bolt. When assembling the entire structure of the ground loop, twisting is not allowed; all parts are connected only by welding.
After the circuit is fully assembled and installed, it is checked for resistance level. If it does not exceed the norm, then the trench is buried. The wire from the ground electrode goes to the power cabinet and is connected to the ground line.
grounding
When checking residential and non-residential premises representatives of the power grid, pay attention to the presence of a ground loop and the correctness of its implementation. Therefore, if you live in apartment building, then you will not do the grounding in the apartment with your own hands. This issue is considered by the developer at the stage of designing the whole house as a whole.
In such ladies, each is equipped with a ground line, to which ground wires are connected from all apartments. Sockets, switches with a three-core cable (with a ready-made "ground") are installed in the apartments. Yes, modern Appliances equipped with cords with a grounding conductor.
Here in country house you have 2 options for the development of events:
- Seek help from qualified professionals;
- Mount grounding in the country with your own hands.
With the first option, everything is clear: you pay money, specialists make a project of a ground electrode system and mount it. But to implement the second option, you need to fully understand this issue.
Consider the functions of the ground electrode:
- Takes voltage from the hulls of equipment, the power of which has been damaged;
- Balances the potential of devices with grounding and communication objects (pipes, gas outlets, etc.);
- Ensures the correct operation of electrical safety systems;
- Neutralizes static stress.
Grounding schemes
If you seriously wondered how to make grounding in the country, then, for starters, you should familiarize yourself with 4 basic schemes.
- The grounding of the building is carried out along the perimeter - the grounding loop has the shape of a square, consists of four vertical grounding electrodes mounted at the corners of the trench. This method is quite laborious due to the large amount of work on digging a trench. In this regard, this type of "land" is not often used;
- The standard scheme is a contour in the shape of a triangle. The advantage of this scheme is that it can be mounted even in a small area;
- The “ground” scheme with one electrode is convenient, but not suitable for all soils. In order for it to fulfill its function, the electrode must be mounted to a greater depth than in the first two schemes. This scheme can be performed even in the basement of the house;
- The grounding installation scheme in the entire lower part of one of the walls of the house is the most expensive and time-consuming. Electrodes are laid when pouring the foundation and erecting the wall. If such a scheme has not been worked out by the project, then its installation upon completion of the construction of the house is practically impossible.
Based on the above, the most popular grounding schemes are "triangle" and "earth" with one electrode.
Grounding with improvised materials
Before starting work on grounding, it is necessary to prepare necessary materials and tools. You will need:
- manual drill;
- sledgehammer;
- welding machine;
- shovel;
- metal corners and tape;
- bolt 10mm
- the wire.
If there are doubts when choosing a grounding scheme, then you can seek advice from the city power grid. The specialists have extensive experience in working specifically in the conditions of your area, so they will tell you which scheme is best to use, what size to make a ground loop.
After receiving advice, you can start work. The circuit must be positioned in such a way that it is convenient to draw a bus from it to the power shield. The optimal distance from the house is 3-6m. It is impossible to have a ground loop closer than a meter to the house and further than 10m from it.
The number of electrodes in the circuit varies depending on the properties of the soil. If there are difficulties when digging the pins to the required depth, then they can be made shorter, but their number can be increased.
The material for the electrodes can be a corner 50x50x4mm, a galvanized pipe 3.5mm, a galvanized circle 10mm. The electrodes are connected to the network using metal strip 40x4mm, or wire rod 14mm. From the strip (rolled wire) a tire is made, which is laid from the contour to the house.
Having chosen the scheme and the installation location of the circuit, a trench of the required shape is prepared. Its depth varies from 0.5m to 1m. From this trench we dig a path to the house for the tire. Both trenches must be the same depth. Next, the prepared electrodes should be hammered into the ground. It is worth noting that the edge that goes into the ground must be sharpened, and the metal should never be painted, as the current conductivity will be disturbed. A segment of the electrode (vertical ground electrode) 20-25 cm in size should remain above the ground level. When the corners are in place, they are connected by welding with a horizontal ground electrode.
A tire is welded to one of the electrodes, which is brought to the house. Near the basement of the building, it is necessary to make a compensatory bend, which will prevent the material from deforming when temperatures change. To extreme point the busbar is welded with a 10mm bolt, and a copper terminal is welded to the bolt. Through a hole in the wall of the house, a wire of 16-25 mm is brought out to the terminal, the structure is connected with a nut, washer. The material of nuts, washers and the cable itself is better to choose copper. All joints are treated with an anti-corrosion agent.
The cable is led into the switchboard and connected to the ground line. At the same time, grounding wires of electricity consumers of the whole house are brought to this line. This ruler must be made of bronze. When performing this work, one must be extremely careful, since the minimum voltage in the shield is 220V.
There is also the option of planting a tire directly into the house. Inside the house, a bronze ruler is attached to it, and grounding wires, consumers, are connected to it, in turn. positive side of this method of grounding is that this part will not oxidize under the influence of natural factors.
When all the work on the installation of the ground loop is completed, it is necessary to photograph the location of its location. This is required for compiling project documentation, as well as carrying out a planned measurement of the resistance of the circuit.
At the end of all work, they call specialists from the city power supply network, because they know how to measure the ground resistance. If the resistance is less than 4 ohms, the ground loop is made correctly and you will be issued permits. Only after all these procedures can you start backfilling the measured contour.
You can also install a pipe on the roof of the house, from which to bring the strip to the ground electrode. This will be a lightning rod. It is only worth considering that the pipe should not be hollow, its top must be sealed.
Now, knowing all this information, you will not have a question that worries many motorists: “How to make grounding in the garage with your own hands?”. Everything is done in the same way as grounding a country house.