How to organize a lightning rod in your home. Do-it-yourself installation of lightning protection in a private house - requirements and recommendations Thunder and lightning or why you need a lightning rod

Historical background or Who invented the lightning rod? Lightning rod (or lightning rod) is a mechanism that is installed on structures and performs the function of protection against lightning strikes. In common people also known as "lightning rod".

It is generally accepted that the lightning rod is an invention of Benjamin Franklin, which he made in 1752, but there is also evidence that similar structures existed before this date (for example, the tall masts of ancient temples in Ancient egypt, there were also structures at the Temple of King Solomon in Jerusalem, the Tower of Nevyansk, Jacques Roma's kites). In Russia, the first lightning rods were created by M.V. Lomonosov and G.V. Rikhman in 1753.

In this article we will talk about what a lightning rod is and how it works, who invented a lightning rod and how to make a lightning rod for country house do it yourself.

Lightning strikes are an extremely dangerous natural phenomenon, especially in a situation where structures are located in open areas, precisely because in order to ensure the peace and safety of your family, it is necessary to install a lightning rod. Installation of a lightning rod does not require a huge amount of time, but in the end, you will be sure that the buildings are reliably protected from various weather troubles.

Necessary funds and building materials

To install a lightning rod in a private house, you will need:

• lightning rod;
• metal wire made of copper or aluminum with a cross section of 6 mm and a corrugation for the down conductor;
• stainless steel for grounding preparation;
• welding machine;
• saw with a disc for metal;
• electric drill;
• multimeter;
• sledgehammer or hammer;
• bayonet shovel;
• spanners;
• bolts M8 or M10;
• dowels;
• clamps for fasteners;
• powerful wooden pole;
• holders.

Preparation phase

Planning should begin with determining the height of the structure. The top of the lightning rod must be located up to 12 meters above the ground.

It should be noted that structures designed to protect buildings from lightning strikes protect buildings only in a limited area. The area around the structure itself can be considered protected. Therefore, when building a lightning rod, it is necessary to take this into account and build them so that all objects located on the site fall under protection.

There are two types of designs:

• Type A
• Type B

Type A lightning rods provide 99% protection, which makes them the most effective lightning protection structures.

Type B structures are less efficient than type A structures and, as a result, protect the structure by only 95%.

Important! The safety zone created by the lightning rod will be within a radius of 1.5 times the height of the mast.

That is, at a height of 10 meters, the lightning rod will cover an area with a diameter of 30 meters. If you need to protect a larger site with buildings, then the construction of two or three masts, evenly spaced across the site, will help solve the problem of lightning. The lightning rod must be at a height of more than 2 meters from the surface in order to effectively perform the function of protecting the house from lightning.

Selection of the grounding installation site

The grounding circuit must be located at a distance of up to 1 meter from the foundation of the building, which will be protected by the lightning rod, and a few meters from the sidewalks and the porch. The grounding place during a thunderstorm is dangerous, therefore it is necessary to arrange it so as not to endanger households and guests. It would be best to find a place for it against the wall or fence that encloses the house. One of the options is to place some kind of flower bed or other composition of boulders, stones, etc. around the grounding zone.

Most suitable materials for components:

It is also necessary to determine and mark in advance the locations of all structural elements.

Installation of the structure

• Installation of an earthing switch.

After marking, with the help of a shovel, a hole in the shape of a triangle is created - each side of which should be at least 1200 mm, depth - 600 - 700 mm. A trench is laid from the apex of the triangle towards the wall of the house. At the end point, the end of the down conductor will come up.

At the ends of the vertical parts of the grounding elements, corners are cut off with a grinder, then with pointed ends they are driven into the ground to a depth of 2 meters with a heavy metal sledgehammer. When driving the pointed ends of the grounding into the ground, it is necessary to strike with a sledgehammer strictly vertically so as not to bend the structure.

Using a welding machine, pieces of the same material are welded, from which a metal triangle is formed in the trenches.

• Installation of a lightning rod (lightning rod).

There are two ways to install a lightning rod:

The pantograph is placed on the roof and then vertically downward on the wall and fixed to the roof and wall with semicircular plastic or metal clips. The lower part of the current sink must be fixed to an earthing ground from the wall of the house.

To do this, a hole is made in the grounding plate, into which a bolt with a washer, nut and locknut is installed. The cleaned (sharp) end of the down conductor is clamped with a washer, nut and bolt, together with a twisted pair wrapped around the bolt. Then the holes are buried.

Examination

The installed system must be checked with a multimeter. Carry out a resistance measurement - the device should have a value no higher than 10 ohms. If the readings of the device differ from the normative ones - check all the joints of the structure - there should be good electrical conductivity along the entire contour of the structure.

Conclusion

A properly installed rooftop lightning rod can protect your home and nearby buildings from lightning.

It is important to note that in the case of private houses, the owner decides on the lightning rod. There are a number of factors in the placement of buildings that, in principle, minimize the likelihood of a lightning strike in a house:

• if the house is located in a lowland, then the probability of a lightning strike into the house during a thunderstorm is extremely small;
• if there is a higher-rise building next to the house, then most likely it will be struck by lightning. Thus, the danger of a lightning strike is leveled by the presence of a higher structure next to it;
• if the lightning rod is installed on a neighboring house, then your house may also fall within the coverage area of ​​the neighbor's lightning rod.

Thus, in some cases, there may not be an urgent need to install a lightning rod. The feasibility of the installation should be assessed depending on the above factors.

DIY lightning protection of a private house, country house and not only

Lightning protection tips from professionals

The destructive power of lightning is understandable: its current reaches two hundred thousand amperes at a voltage of up to one hundred thousand kilovolts. Moreover, there are cases when several lightning strikes at the same place within one and a half seconds. And even one lightning strike into a structure without a lightning rod is enough for it to flare up like a candle. Despite this, small house it is quite easy to protect against lightning.

Above the ridge of the roof (at a distance of at least 25 cm from it), a conductor is stretched - a steel wire 5-6 mm thick (Fig. 1 on page 16). On wooden beams, to which it is attached, vertical lightning rods up to a meter high are installed. The chimney will be reliably protected by a steel cap, wire "plug" or loop connected to the conductor. The same conductor descends the shortest path along the wall of the house and is connected to the ground. If the length of such a lightning rod is more than ten meters, then it should be grounded on both sides.

Lightning most often strikes the ridge of roofs, the edges of gables, dormers and dormers. Therefore, the conductor can be laid on such protruding places, attached directly to the roof of tiles, slate, or mounted on wooden pins or a solid bar on the roof of shingles, roofing tar and other combustible materials. Such a lightning rod is grounded at several points. Wooden parts are painted with oil paint.

A house covered with iron will be completely safe if its roof is grounded three to four times every 10-15 m around the perimeter. How to attach the ground is shown in fig. 2.

B Easy to manufacture and rod lightning rod. At a height of 5 m, counting from the ridge, it can protect a house 15 m long and 7 m wide. A lightning rod is installed on poles 10-15 cm thick, nailed to the rafters in the middle of the roof or dug in next to the house. You can also strengthen the lightning rod on a tree growing next to the house.

It is tied to the trunk above the branches with a soft wire 02-Zmm every 2-3 m. If the house is closer than 5 m from the tree, then a conductor is laid along its wall, connected to the same ground as the lightning rod (Fig. 1).

The upper end of the lightning rod is made of wire of the same diameter as the rest of its parts (or larger - up to 14 mm, steel strips, corners or pipes with a cross section of 50-60 mm2. The pipe at the top is flattened or welded onto a cone, and a loop is made from the wire, fixing its twisting or wire bandage (Fig. 3).

Grounding can also be made of wire, but it is better to make it from steel pipes, for example, water pipes, 040-60 mm, steel strips, corners and other material with a cross section of at least 50 mm2. Grounding is laid at a depth of at least 80 cm (the deeper the better). In the simplest case, a wire or metal strip several meters long is laid in the ditch. You can drive two or three piles from pipes or corners into the ground so that their upper end is at a depth of 80 cm. The piles are connected with a horizontal bus made of steel strip or wire, to the middle of which a lightning rod is attached (Fig. 4).

If the soil is dry, sandy and does not conduct electricity well, then the grounding should be covered with charcoal mixed with table salt (about 0.5 kg of salt per bucket of coal). This will greatly reduce the resistance of the soil: coal is a good conductor, and salt is hygroscopic.

Grounding should be located at a distance of at least 5 m from paths and walkways.

The lightning rod is strengthened on wooden walls ah and poles with staples or clamps nailed at a distance of one or two meters from each other. It is useful to lay insulators from a piece of rubber hose under the clamps. Conductors must be laid so that there are no loops or sharp corners on them, otherwise they can be broken by forces arising from a lightning discharge. They are closed to a height of about 2.5 m from the ground steel pipe, corner or wooden box.

Methods for connecting parts of a lightning rod are shown in Fig. 5. The most reliable are welding or brazing, but twisting, banding, special clamps or overlapping joints using bolts and rivets can also be used.

The contact surfaces must be well cleaned of paint, dirt and rust. The joints (except welded ones) are wrapped with insulating tape, then with a dense cloth, securing it with a thin wire or twine, and all this is painted over without breaking the contact. The paint protects well against oxidation. There must be reliable electrical contact between all parts of the lightning rod.

Every year, before the onset of thunderstorms, the parts of the lightning rod and their attachment points are inspected and, if necessary, they are replaced and painted.

Once every three years, the serviceability of the connections is checked, the contacts are cleaned, the loose connections are tightened or replaced.

Every five years, the grounding electrodes are opened, the reliability of their connection and the depth of corrosion are checked. If the section of the rusted part has decreased by more than one third, it should be replaced.

Technical measures defined as lightning protection country house according to the requirements of the PUE should be considered taking into account the peculiarities of their implementation in each specific case. Indeed, only rare private buildings are located near high-rise buildings with a lightning protection device placed on them. Many of these structures are isolated and require special protection against lightning, which is most often discharged into single objects.

Standards

According to the current regulations (SNiP, in particular), all suburban residential buildings belong to the 3rd class of fire safety and are subject to mandatory equipment with lightning protection equipment.

At the same time, the arrangement of effective lightning protection of a cottage, for example, should be provided for even at the stage of preparing a construction project. This approach to solving the problem allows you to get a reliable fire prevention system, naturally integrated into the architecture of the house being built.

However, many owners of ready-made private buildings would like to protect their home on their own, which requires certain knowledge and skills. How to correctly and without unnecessary problems to mount effective lightning protection with your own hands will be discussed further.

Things to consider when installing

The type and effectiveness of lightning protection, selected individually for each rural building, depends on a number of factors. Here are the most important ones:

• technical condition of a private house;
• its location in relation to other objects;
• the quality of the soil at the location of the protected private building, which ensures good grounding of the entire structure as a whole.

In the case of a dilapidated and poorly protected structure from the effects of natural factors, the likelihood of its being hit by a lightning discharge increases sharply, which will require additional devices for lightning protection from the owner.

Close location of high-rise objects

On the other hand, even completely new private houses can be affected by lightning if they are located in close proximity to antenna towers, large and tall trees or poles.

All of these high-rise buildings are a good target for a lightning discharge and have the so-called "screen effect", in the zone of which a nearby residential building also falls. When calculating the dimensions of the lightning rod mast, the presence of such objects nearby must be taken into account.

Soil condition

The quality of the soil at the location of the house is very important from the point of view of the effectiveness of the ground electrode used as part of the lightning protection, the protective effect of which is based on the discharge of the discharge current into the soil.

In cases where the soil has low electrical conductivity at the dacha or at the location of a suburban private house, it is necessary to worry in advance about artificial measures to increase it. This can be done by adding to the soil aqueous solution table salt or other chemicals.

It is also possible to compensate for the insufficient electrical conductivity of the soil by reducing the resistance of the down conductor and the ground electrode to which the lightning rod is connected in a private house.

However, this option for increasing the efficiency of lightning protection, as a rule, leads to an increase in the cost of consumables and an increase in the cost of the entire system as a whole.

Particular attention should be paid to the choice of reliable lightning protection in a situation where there is a natural reservoir or a key source in the immediate vicinity of a private house. In areas with an indicator of thunderstorm activity more than 40 hours per year, the risk of injury in this case will be maximum.

Lightning rod design

In order to do it yourself for a private country house, you need to familiarize yourself with the principle of lightning protection.

At the moment of a lightning discharge, lightning enters the receiving device (metal pin, cable or mesh), after which it is diverted through a special steel tape directly to the ground electrode.

In this part of the protective chain, current flows into the ground, accompanied by a sharp drop in power. electric charge.

Thus, the independent arrangement of a lightning rod for a private house involves the manufacture of the following mandatory elements thunderstorm protection:

• lightning rod of pin or mesh type;
• reliable down conductor (descent);
• grounding device (lightning protection ground loop).

A typical pin lightning rod is made in the form of a thick steel bar with a cross section of about 10-20 millimeters and a length of about 2.5 meters. During installation, the pin is securely attached at any high point of the roof so that its pointed end rises above this place by at least 2 meters.

Please note that either the ridge of the roof of a private house or a pipe that removes smoke can be selected as an attachment point.

Let's make a reservation right away that the specified version of the lightning rod is ideal for. In the event that the roof of a private house is covered with slate, it is recommended to use a metal cable stretched along the ridge and securely fastened to the insulating supports as a receiver.

For tiled roofs, the most optimal solution is to lay a special lightning protection mesh with a system of wires extending from it over their entire area.

Such down conductors (or descents) are made of a wire with a diameter of at least 0.6 centimeters or a strip of the same metal with a standard size of 2x30 millimeters.

During installation, they are laid along the walls of the building, and then welded on the one side to the lightning rod, and on the other, to the ground loop made according to typical scheme(see PUE).

The procedure for arranging a lightning rod

It is best to start a lightning protection device for a suburban private building with the manufacture of a lightning rod. In this case, the lightning protection pin itself is securely fixed at the highest point of the structure (on a pipe or on a wooden antenna mast). In the case of using a mesh, it is laid over the entire roof area with the formation of cells with dimensions of no more than 12x12 meters (this value is selected based on the dimensions of the roof and the required quality of lightning protection).

At the intersection of the wires, the nets are attached to welding, and then fixed on the roof of the house using special holders, well insulated from the coating material.

Several contact pads are arranged along the lower edge of the grid, intended for connecting the down conductor system (in a typical lightning protection project, two descents are usually laid on each wall of the house).

A part of the lightning protection mesh structure adjacent to the chimney can be made in the form of a loop of the appropriate size, which is thrown over it from above and then attached to the base.

A lightning discharge device prepared in this way will provide high-quality lightning protection for any non-metallic roof of a private house.

Note also that a non-oxidizing material (galvanized steel or copper) should be used for the manufacture of a pin lightning rod, since it is not allowed to paint it by the requirements of standards. In the case when such lightning rods are made of a hollow steel pipe, one of its ends is tightly welded.

The procedure for manufacturing a ground electrode system

The main purpose of lightning protection grounding is to provide ideal conditions for the spreading of the discharge current into the ground.

The fulfillment of this requirement is possible only with a minimum electrical resistance of the entire structure of the ground electrode, made from a set of metal blanks. As a rule, it is constructed of 3 thick steel rods or profiles with a length of at least 2.5 meters, driven into the ground not far from the house (no closer than 5 meters).

These blanks are fixed in the ground in such a way that their tops form a regular triangle with sides about 1.2 meters long.

After that, they are connected to each other for welding using jumpers of the appropriate length, forming a strong and reliable grounding structure.

The structure obtained in this way can be used as a protective grounding for a private house. In the case when the grounding of the house is already available, it can be combined with the lightning protection grounding into one system.

Devices can be specialized electronic circuits and arresters designed to be triggered when a certain electric field strength is reached, and even small amounts of radioactive materials. Active protection systems are much more expensive and more complex than passive ones.

The propagandists of active lightning protection argue that their lightning rods generate longer response streamers earlier than passive ones. This allows you to use fewer lightning rods, and you can place them lower. But, despite such statements, active lightning rods did not find unconditional recognition from specialists.

Passive lightning protection

The principle of operation of passive lightning protection devices is quite simple and is based on the property of lightning strikes the highest and most grounded structures with good electrical conductivity. It consists in intercepting lightning heading towards an object and leading it into the ground, where she will not be able to harm anyone, as well as in mitigating the consequences of her blow for the internal communications of the house.

Passive lightning protection can have rod or cable structure... A rod lightning rod, towering over the protected object, is a classic of lightning protection. In this case, the lightning is intercepted in the protected area at the moment of discharge.

The lightning rod is made in the style of the accompanying

Due to the rise above the protected object and the special material from which it is made, the lightning rod takes the blow and transfers it further through the down conductor to the ground.

Another option for passive lightning protection is cable system when a stretched metal cable serves as an "interceptor". Catenary wire lightning rods are used only for the protection of narrow and long buildings(for example, cowsheds) or if it is not possible to install a sufficient number of lightning rods.

The cable system includes lightning protection mesh... It fits on with a certain step. All these systems are made of durable material with high conductivity - steel, copper, aluminum - which intercept the discharge according to the general laws of physics without generating additional actions.

Lightning protection for a country house

What is lightning protection for a country house? This device to prevent a direct lightning strike... A lightning rod designed to receive lightning and discharge it into the ground serves as a protective device.

The device consists of three interconnected parts, namely:

1. an air terminal located in the zones of expected contact with lightning, that is, above the object;
2. a grounding conductor (down conductor) that removes the charge from the lightning rod to the ground electrode (most often it is a metal wire with a large cross-section);
3. ground electrode - rods and strips buried in the ground.

All parts of lightning protection can be made as a single piece separately standing structure... For example, it can be a metal mast, which is a lightning rod, support, conductor and ground at the same time.

The probability of lightning striking the protection zone is very small. These zones are conventionally divided into two categories - A and B.

• In the category A zone, located closer to the lightning rod, the probability of protection is from 99.5%.
• In the zone of category B, the degree of reliability is somewhat less - 95%.

If the house is completely included in the lightning protection zone, it is safe to say that it will not be hit. A house without a lightning rod cannot serve as a reliable shelter for a person during a thunderstorm.

Lightning protection of a country house is conventionally divided into:

1. external, to neutralize a direct lightning discharge strike into the house;
2. internal- to reduce possible damage internal systems at home.

The internal lightning protection system of a house consists of surge protection devices caused by direct and indirect (for example, near the house) lightning strike.

How to make a lightning rod?

So, a lightning rod consists of three parts: a lightning rod in the form of a rod or cable or mesh, a down conductor for transmitting the resulting discharge to the ground electrode and the ground electrode itself - several metal conductors that are in direct contact with the ground.

For an approximate calculation, you can use a simple rule: the radius of the protected area is 1-1.5 times the height of the lightning rod. Those. with a lightning rod height of 20 m, a circle with a radius of 20-30 m falls under its protection. If this area does not overlap the area occupied by the house, two or more rods are installed at its different ends.

For the device of the simplest rod lightning rod a steel, aluminum or copper rod of the required cross-section, without insulation and stripped of rust and paint, is used as a lightning rod and down conductor. For example, steel wire rod with a diameter of 8 mm. If it is a hollow tube, the open end facing up must be welded.

When such a lightning rod cannot be arranged, the roof of a house can serve as it if:

1. She herself, the supporting beams and joints are metal;
2. The thickness of the steel roofing sheet is not less than 4 mm;
3. There are no flammable or flammable materials under the roof.

A television antenna and raised parts of the roof can also serve as a lightning rod.

If the options considered for some reason are not suitable, then as an alternative, you can place an air terminal at the top of a tall tree standing nearby(the tree should be much higher than the roof of the house).

A catenary wire lightning rod is arranged along the ridge of the roof pulling a metal cable between the two supports. If the supports are not wooden, but metal, then they are isolated from the cable with reliable electrical insulators. The earthing switch can be metal corners, a strip or sheet, buried in the ground to a depth of at least 0.7 m and at a distance of 1 m from the wall of the house.

To connect the structural elements of lightning protection, welding or threaded fasteners are used. The main thing that the connection was sure to be strong, then a strong gust of wind or a fall of a snow layer will not be able to break it.

If your house is made of stone, then the down conductor bus can be "run" right along the wall. And if the house? In this case, the down conductor is made at a distance of about 10 cm and is mounted on electrically insulated brackets.

When arranging lightning protection even for a small one-story country house need to be guided:

1. Instructions for the device of lightning protection of buildings and structures RD 34.21.122-87 and
2. Instruction on lightning protection of buildings, structures and industrial communications SO 153-34.21.122-2003.

It is these documents that will tell you all the nuances of lightning protection and provide the house with a reliable "roof".

However, the lightning protection system of a country house, with all its simplicity, has subtleties to consider during its design and operation. For example:

• For a metal roof, lightning protection using a rod is possible, and for a polymer roof, a mesh.
• For a slate or wooden roof, it is better to use a catenary wire lightning rod.

Every year you need:

• inspect all parts of the lightning rod,
• check the serviceability of connections and fasteners,
• change damaged places,
• clean contacts, etc.

About every 5 years- check the depth of corrosion of the earthing switch.

Today, when putting a house into operation, the presence of lightning protection is not required, therefore each homeowner decides on his own whether it is advisable to install it. Let's not wait for the thunder to strike. Moreover, it is heard only a few seconds after the next "fiery arrow" pierces the ground.

Is your home reliably protected from lightning strikes?

Most owners of private houses, cottages and summer cottages are trying to create the most comfortable and safe living conditions inside and outside their homes. It is quite understandable aspiration, but most often the owners of such real estate completely forget about such a natural phenomenon as a discharge of static atmospheric electricity, which in an instant can cause enormous harm to residential buildings and human health. In its natural essence, atmospheric lightning is a very powerful discharge of electrical energy, which is capable of accurately hitting directly into private house, destroy not only all household appliances and electrical appliances, but the building itself as a whole.

If your private property is located next to a tall building, then you shouldn't worry. The lightning rod system of a multi-storey building will provide reliable protection of your home from the damaging factors of atmospheric electrical discharge. But such an arrangement of cottages, private houses and summer cottages practically does not occur in modern reality. Basically, such real estate objects are built away from tall buildings, so they need to be protected from lightning by equipping them with modern lightning protection units.

Lightning is most often discharged to the highest point, but even a huge tree growing next to the house is not able to protect it from the discharge. Only a lightning protection device is able to fully protect your home with household appliances from an atmospheric discharge, as well as the people present in it. In this article we will consider all the issues related to the types of lightning protection and methods of their installation for all types of houses, summer cottages and cottages. And also, in a concise form, we will tell you how to install a lightning rod with your own hands, but first, we will tell you about the damaging factors of lightning.

Damaging factors of atmospheric discharges

The technology of creating protection against thunderstorms is directly related to the damaging factors of atmospheric electrical discharges. Any a natural phenomenon affects environment with varying degrees of impact. Lightning is no exception and its damaging factors can be divided into the following two types.

You can protect your property from a secondary damaging factor by simply disconnecting electrical appliances from the mains for the entire period of the passage of the thunderstorm front. For effective protection against direct lightning strikes, it is necessary to install lightning protection in a cottage, private house or in the country.

Installing a lightning rod and additional protective equipment will avoid negative consequences from the impact of the discharge on your residential property and on the people living in it, regardless of the type of damaging factor. Next, we will consider the types and categories of lightning protection.

Categories and types of external lightning protection

Atmospheric lightning is a powerful discharge of electricity that obeys the basic laws of physics. Everyone knows that an electric current moves along the path with the least resistance. The main task of the lightning protection unit of any kind is to create just such a path for the passage of electricity, bypassing the structure of the building. When lightning strikes a private house equipped with such a unit, all the power of the electric charge will simply go to the surface of the earth, without causing damage to buildings, electrical appliances and humans.

In popular slang, this type of protection for private buildings is called differently: grounding of a country house, a system of lightning rods, and also lightning rods. The last option the name is completely incorrect, because thunder is the sound of a lightning strike and there is no need to take it anywhere. But the term has long stuck and is used in colloquial speech... Regardless of how the protection of a house from lightning is called, it is designed to perform one task - to dissipate the energy of an atmospheric electrical discharge into the ground. Lightning protection units are divided into three categories: by method and type of protection, as well as by design features.

The next chapter of the article will help you choose the best protection against the discharge of atmospheric electricity for your home, in which we will tell you about the design of the most popular passive external lightning protection, in addition to which it is necessary to install internal protection against a secondary damaging factor.

Passive external lightning protection design

The design of an external lightning rod in the country, in a cottage or a private house is quite simple. It consists of three components: a lightning receiver, down conductors and a ground loop. Down conductors and earthing switches are of a standard design. In contrast, lightning rods of passive protection systems can be divided into three types, which we will consider in detail below.

What type of lightning rod to use is up to you! It is impossible to give any strict recommendations on this score. All three types of lightning rods are able to reliably protect a private house from the primary damaging factor of lightning.

The next elements in the lightning protection system are down conductors. Their main task is to transfer atmospheric discharge energy from the lightning rod to the grounding device. Down conductors can be made of steel wire with a diameter of at least 6 mm, a special copper or aluminum cable or steel tape 30 mm wide and more than 2 mm thick. Any down conductor is fixed at the ends of the lightning rods using threaded connection, welding or soldering. In private houses built of non-combustible materials, this lightning protection element is attached to the walls in an inconspicuous place using metal fasteners. Do not place down conductors near windows and doors.

Special requirements apply to the installation of lightning protection down conductors wooden house... If lightning strikes the lightning protection system in a private house, the wires of the down conductors can heat up to high temperatures... To exclude the fire of the wooden walls of the building, it is necessary to correctly install the current-carrying part of the lightning protection system. Down conductors must be located at a distance of at least 10 cm from the walls of the building. For one rod lightning rod, it is necessary to install one down conductor, and for cable and mesh discharge receivers, two down conductors. The number of down conductors depends on the number of lightning rod ends and the area and structure of the roof.

The last element in the system of external protection of a private house from atmospheric electrical discharges is the grounding device. The simplest ground electrode system is two metal rods with a diameter of at least 30 mm, hammered into soil layer by 2-3 meters and connected by a jumper made of metal tape. The distance between these grounding elements must be at least 3 meters. The down conductor is connected to this structure exclusively by means of a welded connection.

We examined the design of external passive lightning protection. It is able to effectively protect a private house from the primary damaging factor of lightning. To protect a house, cottage or summer cottage from overvoltages in the network arising from the impact of the second damaging factor of a lightning discharge, it is necessary to install optional equipment... These devices provide internal lightning protection.

Internal lightning protection

Household appliances and electrical appliances in a private house should be protected from the effects of a powerful induction field that occurs as a result of an atmospheric discharge. External lightning protection is unable to cope with this task. To protect against lightning overvoltages, it is necessary to use special electrical devices. They are called surge protection devices (SPDs) and are installed in switchboards at the entrance of electrical lines to a private house. Currently, there is a large assortment of such devices on the market, with different possibilities and the level of protection against impulse voltage surges.

Only after installing an SPD in the switchboard and installing external lightning protection, you can confidently say that your house is reliably protected from all the damaging factors of lightning. We examined the design of lightning protection for a private house, both external and internal. The next part of the article will answer the question: how to make a lightning rod in the country, in a cottage or a private house with your own hands.

Self-assembly of lightning protection

Based on the foregoing, we can conclude that the installation of lightning protection can be done by hand without the involvement of hired workers. Of course, if you have basic skills installation works... Otherwise, you should invite a specialist. If you nevertheless decide to install a lightning rod with my own hands, then you should first perform the design and calculation of lightning protection. This process is straightforward. We will briefly talk about the design of lightning protection and its self-assembly on the example of installing a lightning rod with a rod lightning rod. This is the most popular option for protecting suburban real estate from thunderstorms.

A lightning rod with a rod lightning receiver provides protection in the form of an imaginary cone, with the apex at the end of the lightning rod. To the inner zone of this cone, to ensure reliable protection structures from lightning, the entire object must fall.

In the above figure, we see that part of the house did not fall into the protection zone, therefore it is necessary to move the lightning rod to the middle of the house or increase its height. The best place to mount the lightning rod is at the ridge or chimney. The calculation of the height of the rod receiver is calculated using the following formula.

• Rx is the lower radius of protection of an imaginary cone, which must be measured with a tape measure on the surface of the earth;
• Ha - height core lightning protection, which is measured from the ground to the highest point of an imaginary cone;
• Hx - the highest point of a private house, which can be located on the ridge of the roof, chimney or other structural elements;
• H is the height of the lightning rod.

After calculating the length of the lightning rod, it is necessary to determine its location and lay an imaginary route for mounting the down conductor from the rod to the installation site of the earthing switch. This completes the design and calculation of lightning protection and you can proceed directly to the installation of the lightning rod.

Earthing switch installation

First of all, you should install the ground loop. To complete the work, you will need the following tools and materials:

• grinder with cut-off wheels, welding machine, sledgehammer, hammer and shovel;
• 40 × 40 steel angle for vertical pins and 40 × 5 strip for jumpers.

The earthing switch should be installed near the wall of the house. We choose a place and dig an equilateral triangular trench 70 cm deep with sides of 1.2 meters. It is also necessary to dig a trench to the wall of the house to lay the down conductor. In the corners of the triangle, we hammer in pieces of a steel corner to a depth of 2 meters.

A strip is welded to the ends of the pins. A steel strip is welded to one corner of the circuit and brought out to the wall of the house, where a down conductor from the lightning rod will be connected to it. The trench is buried and compacted. The earthing switch is ready to connect the down conductor.

Lightning receiver installation

The best place to attach the air termination rod is the chimney located near the roof ridge. It is most convenient to fasten the mast with brackets with clamps at the ends.

An alternative option for fastening the lightning rod is to install it on a special support on the ridge of the house.

On final stage installation, the down conductor is attached to the lower end of the rod using a clamp with a threaded connection.

Installation of down conductors

A down conductor, a metal wire with a diameter of at least 6 mm, is laid directly along the roof and wall of the house, to the exit point of the connecting steel strip from the ground loop. The entire structure is attached to the roof and walls of the house with plastic or metal clamps with support.

The lower end of the down conductor wire is fixed to the metal strip of the earthing switch using a threaded connection.

This completes the installation of the external lightning protection, but if you do not install the internal overvoltage protection unit, then your lightning protection system will be incomplete.

SPD installation

The surge protection device completely de-energizes the electrical network of the house in the event of a powerful induction field, that is, a secondary damaging factor of lightning. The module is installed in the switchboard according to the following diagram.

After installing an SPD, your lightning protection of a private house gets a fully finished functional look. With this system, your property and household appliances are reliably protected from atmospheric electrical discharges.

Conclusion

High-quality installation of a lightning rod will provide you comfortable accommodation in my house. In this case, protection against all damaging factors of lightning will be provided. But it should be noted that lightning protection must be periodically checked for damage. The main attention during a preventive examination should be given to all connections. Only if the lightning rod is operational, your home will be reliably protected from lightning strikes.

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