Lightning in a wooden house. We protect the house from lightning - we make a lightning rod with our own hands

From a school physics course, it is known that lightning is an electrical discharge of enormous magnitude, which carries a large amount of thermal energy. The consequences of a lightning strike can be catastrophic, so at all times mankind has tried to create devices and devices that would protect them from this natural scourge. V modern world lightning protection of a private house is a combination design features buildings and special devices designed to divert electricity into the ground. The latter is called a lightning rod, how does it work, what are the requirements for it?

Types of lightning protection

Lightning protection at home is divided into two categories: internal and external. The purpose of the first is to protect against lightning, the lightning discharge of which did not hit the house itself. For example, it can get into a power line that connects to the internal electrical wiring of a house. In this case, high overvoltages occur in the internal wiring. The result is the failure of most household appliances. In any case, the one that was plugged into the sockets at that time. The wires may burn out, a short circuit will occur, the worst case scenario is a fire if the wiring was carried out according to hardwood floors or the house was wooden.

You can solve this problem by setting electrical network special devices that will protect it from impulse surges. For example, surge arresters, all kinds of arresters, SPD (surge protection device). All devices are installed in the switchboard of the house.

External protection

External lightning protection is a lightning rod, which consists of three main elements:

lightning rod;
down conductor;
ground loop.

The main requirement for all three elements is reliable connection them among themselves. Depending on the roofing material, it is necessary to use different types of lightning protection. There are three of them: pin, cable and mesh.

It is usually used if the roof of the house is covered with metal roofing material. For example, metal tiles, corrugated board or tin. To do this, you need to install a metal pin on the roof, which will rise above the ridge of the roof of the house, approximately 1-2 m higher. This will be the lightning rod. You can make it from a metal bar with a diameter of 8-12 mm, you can also use a steel strip 4-5 mm thick and 25-35 mm wide for this.

Such a lightning rod can divert electrical shocks around the house with an area equal to the area where the radius is the height of the lightning rod. And the higher the pin is installed, the larger the area that it protects from lightning strikes.

The diverting ability of a lightning rod is not based on the size of the area it covers. If we take into account that the vertical line of the pin installation is the height of an isosceles triangle, then the base of this figure will be two times the height. It turns out that a circle with a radius equal to the height of the pin installation can form on the soil surface.

Rope

For this lightning rod, a cable is required, which is stretched along the roof ridge, and it is suspended at a height of half a meter above the installation level of the ridge. To do this, it is best to use a cable made of galvanized wires with a total minimum cross section of 5-7 mm. This lightning protection is applied if the roof of the house is covered with slate.

The cable is pulled along the ridge and attached to wooden posts installed along the edges of the ridge beam. If the roof is long, then there may be more racks, the main thing is to observe a slight sag in the cable. A strong sag is unacceptable, because in this way the distance from the roof ridge to the lightning rod decreases. And it should not be less than 1 m. The mounting method is varied, the strength of the installation is important here. You can fasten it with clamps (metal or plastic), if the cable is thin 5-8 mm, then you can simply tie it and additionally tie it with wire.

Mesh

This is a more complex structure that is installed on roofs covered with tiles. It is not easy to make such a lightning rod with your own hands. For this, steel wire rod with a cross section of 6-8 mm is used, which is laid over the entire surface of the roof slopes in the form of a grid with cell sizes of 6x6 m and more, it all depends on the roof area. All connections are welded, fastening to the roof with brackets.

As for the down conductor, this is a line connecting the lightning rod with the ground loop. Usually, steel wire rod with a diameter of 6-8 mm is used for this. It is important here that the current-carrying element can withstand a large current, which often reaches 200,000 amperes. If ready-made protection is chosen, then its down conductor is a copper or aluminum wire with a diameter of 6 mm.

Requirements for the conductor.

This should be the shortest path from the lightning rod to the ground loop.
It is impossible to use bends and creases when laying, which will become a place of occurrence of a spark charge during the removal of electricity, leading, as practice shows, to ignition.
The laying route is chosen so that the wire does not pass near windows and doors.
If a lightning protection device is produced wooden house, then the installation of the down conductor is carried out at a distance of 15-20 cm from the surfaces of the wooden structure. For this, they are used special staples. They are a metal clip, the base of which is made of hard and durable plastic. It is plastic that protects the conductive element from contact with wooden structures Houses. The bracket is attached with self-tapping screws. By the way, these brackets are also used in the construction of a mesh lightning rod, where the distance between them is 1.5-2.0 m.
If the protection of buildings and structures from lightning is a large mesh structure, or a long laid cable, or several pins are used on the roof, then there should also be several down conductors, the distance between which is 25 m (according to SO 153-34.21.122-2003).
Wire rod is carried out along the walls of the building, along the gables and sharp ledges of the roof. That is, in those areas that can be struck by lightning.

Ground loop

The lightning protection circuit in a private house is carried out according to the same scheme and design as the grounding of electrical networks.

One meter from the foundation of the house and at least five meters from the front door, paths, and platforms, trenches are dug in the shape of an equilateral triangle. The depth of the trenches is 80 cm, the width is 60 cm, the length is 1.5-2 m.
In the corners of the triangle, pins are driven in from a steel corner with dimensions of 50x50x5 mm. The depth of penetration is 2-3 m. The corners should not be completely driven into the ground, the height of the free protruding segment is 20-30 cm.
Between themselves, the pins are connected by a steel strip 4 mm thick, 40 mm wide. You can use the same corners for these elements as for pins.
This ground loop of lightning protection is connected to the down conductor.

Attention! All connecting joints must be fixed by electric welding. Bolted connections are not welcome, because during the operation of the lightning rod of a country house, they can weaken, rust and weaken the conductive capabilities of the entire structure.

DIY assembly

Before you make a lightning rod in a private house, you need to decide what type of lightning rod to choose. If this is a pin option, then the pin itself must be installed not on the roofing material, but on the crate.

After that, a conductive wire is laid with your own hands. If the length of the purchased piece of wire or wire rod was not enough, then you can connect two segments using an aluminum or copper contact, which is used in overhead lines power transmission. The distance between the brackets is 1.5-2.0 m.

A grounding loop is being constructed, to which the down conductor is attached. Before welding, all joints of the elements must be cleaned to a metallic sheen. If ready-made lightning protection of a private building is used, then they are used as a connection special devices on bolted connections made of non-ferrous metal.

Attention! The best option is if the ground loop and lightning protection are located close to each other and connected to each other with a wire rod or a strip. This does not violate the standards of the lightning protection device, in addition, the circuit becomes twice as large.

When installing lightning protection in your own private house with your own hands, you need to understand that this is a safety element not only for the building, but also for the people living in it. Therefore, it is not necessary to postpone its installation indefinitely. The ideal time for installation is the construction of a private house with your own hands.

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Before considering the process of calculating and installing a lightning rod in a private house, you need to find out the physical causes of the phenomenon. This will allow you to better understand all the actions and possible consequences in case of violations of the developed instructions.

Thunder - air waves that appear due to sharp increase air pressure after lightning contact. The current in lightning can reach 500 thousand amperes, and the voltage is several million volts. Such a powerful eclectic discharge causes the air to heat up to high temperatures, and its volume increases sharply. As a result, sound waves from lightning arise, which are called thunder. Thunder is a consequence of lightning and does not pose any danger to the house; it is necessary to protect buildings not from it, but from lightning.

Accordingly, to build not a lightning rod, but a lightning rod.

Why do you need a lightning rod

Some not very literate developers think that a metal pin attached to the ridge of the house will attract all the lightning along a cylindrical circle above it and lead them to the ground along the wire. For this purpose, a piece of wire rod is specially buried near the house. Such ideas are very far from science, a metal pin stuck in the ground near the house and tied to a rod on a skate will not bring any benefit. Why?

Where can I find a wire that can withstand a current of 500,000 A and a voltage of 1,000,000,000 V? It is this kind of discharge that lightning has when it meets the ground.
Why, in principle, attract lightning and direct it along the wire, risking setting fire to the building due to overheating of the down conductor?
What to do if on suburban area several buildings of different heights? Will we have to make a lightning rod system for everyone?

Conclusion. It is necessary to mount not a lightning rod, but a lightning rod. All actions should be aimed not at attracting lightning, but on the contrary, at creating conditions that minimize the likelihood of it entering the structure.

This is very complex calculations, simplified formulas give a large error. Sometimes it is not possible to fulfill the initial specifications, there may be several reasons, some of them are objective and not amenable to human influence.

Prices for lightning protection and grounding

Lightning protection and grounding

When you need to install a lightning rod in a private house

Again, we need to remember a little theory about lightning - the actions during the installation of a lightning rod will become clearer. There can be several types of lightning, but we are only interested in the cloud-to-ground direction. At the initial stage, streamers appear, which later combine and form stepped leaders. It is they who glow brightly and are rapidly heading towards the earth.

As it approaches, the voltage of the eclectic field on the earth increases, all the electrons in it rush upward and at the highest point throw out a response streamer towards. It connects to the leader, the circuit closes, the electric discharge goes to the ground. The channel heats up to 20,000–30,000°C, the air expands and creates strong sound waves (thunder).

Now it will be clearer when it is necessary to mount lightning rods on the house.

If the earth in the area has a large number of ions. Such zones are located in waterlogged areas, they can accumulate a large amount of charge. Pay attention to how often lightning occurs in your area, talk to the old-timers. If they cannot remember cases of lightning strikes in any objects, then there is no need to mount a lightning rod.
The house is located on lands capable of accumulating a charge, lightning strikes are not uncommon in this area. Installation of a lightning rod is mandatory, but you must strictly follow the installation rules and perform preliminary calculations.

How lightning rod works

An effective lightning protection system is aimed at minimizing the direction of stepped lightning leaders into the building area. And for this there is only one condition - electric potential land on this site should be minimal and necessarily much smaller than on neighboring ones. This task should be performed by lightning rods. They constantly, and not only during a thunderstorm, send into the atmosphere electric charges and thereby significantly reduce the voltage potential. The conditions for the appearance of oncoming streamers disappear, lightning finds other points of energy removal.

Important. If lightning strikes a lightning rod, it means that it is installed incorrectly and causes harm instead of good.

The size of the protected area depends on the quantity and quality of the ground rods, they collect electrons and send them through the wires to the vertical rod of the lightning rod. From there, the electrons gradually pass into the atmosphere. Due to this continuous process, the potential under the house is reduced and the probability of lightning strikes is automatically minimized.

Now that the principle of operation of a lightning rod is clear, the tasks of each element of the system are clear, you can proceed to install protection at home.

Step by step installation instructions

As it is already clear from the above, lightning protection should be installed only in combination with effective grounding, otherwise the system will not function.

It is recommended to proceed to the work only after calculating the number, size and location of the ground electrodes. Only qualified specialists can perform such calculations. By the way, after installation, they must check the effectiveness of grounding with special devices (megohmmeters), if the indicators turn out to be unsatisfactory, then it will have to be corrected or completely redone.

Step 1. Bend the tendril of the wires, assemble the two halves of the ridge holders.

They are made in such a way that with the help of adjusting holes and screws it is possible to change the main parameters. The elements can be firmly fixed to skates of various sizes, while the reliability of fastening is maintained for the entire period of operation, spontaneous unscrewing is completely excluded.

Step 2 Attach down conductor holders to the ridge. If you are buying an industrial lightning protection system, great, it has all the elements necessary to install the equipment. You can make them yourself, but this will take additional time. In addition, handicraft holders lose significantly in terms of design form and do not decorate the building in any way.

The distance between them is about one meter, care must be taken that the wire does not touch the roof covering. Try to fasten with the same pitch, so the system looks much better and does not adversely affect the appearance of the house.

Practical advice. On rooftops, always work with a safety rope, especially metal roofing. If it is not possible to purchase industrial equipment for climbers, then make an elementary one yourself.

Lambs (nuts) tighten strongly, use open-end wrenches or pliers. Remember that it is difficult to correct the mistake made later, you will have to climb onto the roof again. Pay attention to everything vertical racks to install the wires were located strictly on the same line.

Step 3 Start laying the wire on the ridge holders. It should be even, the diameter is calculated by a specialist, but in most cases it cannot be less than 6 mm. It is desirable that the surface of the wire be coated with a layer of zinc, due to this, performance characteristics are significantly improved.

The wire is not covered with rust, brown streaks do not appear on the roof. Traces of rust greatly worsen the appearance of the structure.
Due to the fact that the wire does not rust, the resistance indicators remain unchanged for a long time. And this is very important parameter any lightning rod.
At the joints, the resistance decreases, during operation it does not worsen the physical and electrical characteristics.

It is not worth saving on the quality of all lightning protection elements, otherwise the efficiency will be insufficient, the money for the purchase and installation can be considered wasted. Clamp the wire with special tongues with pliers.

Step 4 Bend the end of the wire protruding beyond the slope at a right angle, leave a piece about 50 cm high, cut off the excess with special wire cutters.

Step 5 Smear threaded connections special mastic, if it is not available, then you can use ordinary grease. Mastic additional protection metal surfaces from oxidation. The fact is that during the tightening of the nuts, the zinc on the thread breaks off due to strong friction, and the opening of the metal requires protection.

Step 6 Proceed with fastening the wire on the slopes in the longitudinal direction. Here the installation technology depends on the type of roofing material.

Single wave metal tile. It is necessary to loosen the screws a little, lift the sheet and insert the mounting bracket into the gap formed. It has a curved leg shape that goes into the recesses of the metal tile and is firmly fixed in it. Tighten the roof fixing screw. Install the wire and clamp it with tabs.
Piece tile. For such a roof there are special brackets, they have an increased leg length and several notches with tongues. Before installing the bracket, the tongue must be bent at a distance equal to the length of the piece tile, due to this, the strength of the fastening increases. Then you should lift the tile and slip the bracket under it; when the roof is lowered, it is fixed in a fixed position. The wire is attached to it in the usual way.
Sheet metal tiles. For fastening the wire, special brackets are sold, which must be fixed on top of the roof with self-tapping screws. It is necessary to ensure that the self-tapping screws must fall into the boards of the crate. Two rubber gaskets are used to seal the hole. One is installed between the bracket and the roof surface, and the second between the bracket and the washer of the self-tapping screw.
Flexible bituminous tile. This roofing has a solid base, which greatly simplifies the technology of fixing brackets. They are screwed to the surface with ordinary wood screws, rubber linings are used to seal the holes.

Practical advice. There are situations when, according to the lightning rod project, it is required to transfer one wire from the front slope to the rear one. At the intersection with the ridge wire, it is recommended to connect them, use elements with bolted tightening for this. Thus, you will achieve reliable contact of down conductors.
Prices for down conductor holders

Holders for down conductor

Step 7 Screw the brackets to the edge of the gutter of the drainage system, the wire is fixed to them with bolts. Tighten connections with great force.

Down conductors installed on the house are connected to grounding.

Grounding manufacturing

This is the most important element of the lightning rod, as already mentioned above, only a specialist with a special education should calculate the parameters. He must know the resistance of the soil, its composition, the proximity of groundwater and other initial data. Based on the calculations, the material is selected, the manufacture of metal pins, the distance and quantity, the depth of burial for each grounding. Depending on the size of the house, a specific location of grounding conductors is selected.

Prices for voltage stabilizers

Surge Protectors

For steel pins, the cross-sectional area must be at least 80mm2, for copper 50mm2. It must be remembered that both steel and copper oxidize at different rates, and oxides negatively affect current conductivity. The cross section and surface area of the rods must be chosen with a margin, and resistance measurements should be taken annually. Upon reaching critical values it is recommended that the rods be dug up and cleaned of rust.

The depth of the trenches is not less than 5.0 m, the length is not less than three meters. These indicators largely depend on the physical characteristics of the soil, decisions are made by a specialist at the work site.

All ground connections are best done by welding, clamps quickly lose their initial resistance values. Welding is mandatory on both sides, the seam length is at least five centimeters.

Professionals advise instead of round pins to use a metal strip with a thickness of at least 1 mm and a width of about three to four centimeters. Such metal is not only cheaper, but also significantly increases the operating time of the lightning rod due to the large area of contact with the ground.

To make or not to make a lightning rod is the business of every developer. Strict requirements are established only for public buildings and premises with large quantity people. There are no exact statistics on the system's performance, no one knows how many lightnings were managed to be removed from the building and what the efficiency of the device is.

Now you know how to properly mount a lightning rod in a private house. But once again we remind you that before starting work, you must carefully analyze all the factors that affect the likelihood of a lightning strike into a building, and only then make a final decision. In order for the installation of a lightning rod to give the expected effect, the roof of the house must comply with existing building codes.

Video - Installation of a lightning rod

Country houses are usually built of combustible materials, and the fire station is far away. Yes, and you can not drive up to every building, but from the strong wind that accompanies any thunderstorm, nothing good should be expected either.

Sometimes entire holiday villages burn out from a lightning strike.

Let's talk about how to make an effective lightning rod on your own and negate the risk of a direct hit of a "heavenly discharge" in the house.

Where do lightning come from

In a simplified way, the physics of the process can be described as follows: the source of lightning is cumulonimbus clouds.

During a thunderstorm, they turn into a kind of giant capacitors. A huge positively charged potential of ions accumulates in the upper positive part in the form of ice crystals, and negative electrons collect in the form of water drops in the lower negative region.

During the discharge (breakdown) of this natural battery, lightning appears between the earth and a thundercloud - a huge electric spark discharge:

This discharge will always flow through the circuit of least local resistance. electric current. The fact is well known and proven. Such resistance is usually found in high-rise buildings and trees. Most often it is in them that lightning strikes.

Do-it-yourself lightning rod

The idea of a lightning rod is to arrange a section of minimum resistance near the house so that the lightning discharge passes through it, and not through the building.

If you do not have a lightning rod in your dacha, it's time to think about its construction. The cheapest and easiest way to make it is to do it yourself. What do you need to know for this?

So, a lightning rod (lightning rod) is a lightning protection (lightning protection) device that ensures the safety of a building and the lives of people in it from the destructive effects that can occur in a thunderstorm with a direct lightning strike.

It is a corrosion-protected, bare conductor - that is, a material that conducts electricity as well as possible. larger area and larger cross-section (minimum 50 mm²).

A lightning rod (lightning rod) is assembled from thick copper wire or steel rod, pipes of the required section or from steel, aluminum, duralumin rods of various profiles, corners, strips, and so on.

Steel materials are better to use galvanized. Since they are less susceptible to air oxidation.

What lightning protection consists of: device

Lightning rod (lightning rod) the simplest design consists of 3 parts:

Lightning rod.

Down conductor (descent).

Grounding.

Let's talk about each element in more detail.

Lightning rod

Lightning rod - a metal conductor fixed on the roof of a building or on a separate support (tower). It is structurally divided into three types: pin, cable and mesh.

When choosing the design of a lightning rod, be guided by the material that covers the roof of the house.

1. A pin (or rod) device of a lightning rod is a metal vertical rod that rises above the house (see the figure below).

Suitable for a roof made of any material, but still preferable for metal roofing. The height of the lightning rod should not exceed 2 meters. And it is attached either to a free-standing supporting support, or directly to the house itself.

Materials for manufacturing:

Steel pipe (20-25 mm in diameter, with a wall of 2.5 mm thick). Its upper end is either flattened or brewed into a cone. You can also make and weld a special plug in the form of a needle to the upper edge of the pipe.

Steel wire (8-14 mm). Moreover, the current collector must be exactly the same diameter.

Any steel profile (for example, angle or strip steel at least 4 mm thick and 25 mm wide).

The main condition for all these steel materials is a minimum cross section of 50 mm².

2. The cable device of the lightning rod is a cable stretched along the ridge at a height of up to 0.5 m from the roof with a minimum section of 35 mm² or wire.

Usually galvanized steel wire is used. This type of lightning rod is suitable for wooden or slate roofs.

It is fixed on two (1-2 meters) supports made of wood or metal, but insulators must be installed on metal supports. The cable is connected to the down conductor with the help of flat clamps.

3. The mesh device of the lightning rod system is a mesh laid over the roof with a thickness of 6-8 mm. This design is the most difficult to implement. It is applied to the roofs covered with a tile.

4. And very rarely, a lightning protection cover is used - this is when metal structural elements of the house itself act as lightning rods (roof, trusses, roof fencing, drainpipe).

All considered designs of lightning rods are securely connected by welding with a down conductor and through a down conductor with a ground electrode with a one- or two-sided weld of at least 100 mm in length.

Down conductor

Down conductor (descent) - the middle part of the lightning rod, which is a metal conductor with a minimum cross section for steel 50, for copper 16 and for aluminum 25 mm squared.

The main purpose of the down conductor is to ensure the passage of the discharge current from the lightning rod to the ground electrode.

The ideal path for the passage of electric current is the shortest straight line directed straight down. Avoid turning at an acute angle when installing the lightning rod. This is fraught with the occurrence of a spark discharge between closely located sections of the current collector, which will lead to inevitable ignition.

The most popular material for the down conductor is uninsulated steel wire rod or strip. It is carried out only on fireproof surfaces. Metal brackets should be installed on combustible walls, which themselves, being in contact with a combustible surface, will protect the down conductor.

The minimum distance from the wall to the down conductor is 15-20 cm.

It is necessary to lay it so that there are no points of contact with such elements of the house as a porch, Entrance door, window, metal garage door.

We know that it is better to connect the parts of the lightning rod by welding, but if this is not possible, it is allowed to pair the down conductor with the ground electrode and the lightning rod using three rivets or two bolts. The length of the current collector overlay on other parts of the system with a riveted connection is 150, and with a bolted connection - 120 mm.

The end of the non-galvanized wire rod and the place where the wire down conductor is attached to the steel parts must be cleaned to ensure reliable contact, and the galvanized wire must be cleaned from dust and dirt. Then, a loop or hook is made at the end of the wire, put washers on both sides and tighten it all with a bolt as much as possible.

The joints (if it is not welding) also need to be wrapped in several layers with electrical tape, then with a coarse cloth, twisted over with a thick thread and covered with paint.

To improve contact, you can treat the ends of the wire with tin and solder.

grounding conductor

Grounding conductor (grounding electrodes) - located in the ground, the lower part of the lightning rod, providing reliable contact of the down conductor with the ground.

How to properly equip grounding is described in GOSTs and SNIPs, but for the simplest option, it is enough to bury a U-shaped structure of metal conductors no closer than 5 meters from the entrance to the building at least one meter from the edge of the foundation and no closer than 5 meters from the entrance to the building.

A conventional ground loop is able to cope with the task (it is made for household electrical appliances).

These are 3 electrodes hammered and buried in the ground, connected to each other at the same distance by horizontal ground electrodes. Burying the grounding structure should be below the maximum level of soil freezing. From 0.5 to 0.8 meters deep.

For the ground electrode, rolled steel with a cross section of 80 mm is taken, less often copper with a cross section of 50 mm squared. Vertical ground electrodes are 2-3 meters long, but the closer the water table, the shorter they are.

If the soil in your country house is constantly wet, then a meter or half meter pin will suffice.

At what depth to hammer and how many electrodes will be needed, you can find out in the energy service at the place of residence.

It must be remembered that the quality of grounding depends on the size of the contact area of the ground electrode with the soil and the resistivity of the soil itself.

A grounding conductor for a lightning rod is needed separately, it is not necessary to ground a lightning rod to a household circuit. We strongly advise against experimenting. It is fraught with consequences.

We offer you to watch a video with a visual diagram of lightning protection installation:

According to regulatory documents, for private residential buildings, installation of lightning protection systems is optional. And only you can decide whether it is advisable to install a lightning rod (lightning rod) in the country. We hope this article will help you the right decision.

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We protect a private house from lightning - an overview of a good lightning rod

A reliable lightning rod in a summer cottage will not only protect a person from being struck by lightning, but also a house from fire, especially if it is wooden. Consists good system lightning protection from a grounding conductor, down conductor and lightning rod. Next, we will tell the readers of Sam Electric about what all the elements of the system should be like and how to make a lightning rod in a private house with your own hands!

How the system works

To begin with, let's look at how the lightning protection of a private house works and what is needed to create it. You can clearly see all the constituent elements of the system in this diagram:

As you already understood, the metal rods on the roof are lightning rods that divert a dangerous discharge to the ground through a down conductor and special grounding.

There is an opinion that if a telephone tower is installed near the house, you can not make a lightning rod in a private house. This is wrong, because it is better to spend a little time and provide yourself with complete protection against a lightning strike. In order for you to know what a lightning rod should be and how to make it correctly with your own hands, below we will separately consider the features of choosing each of the elements of the system.

A brief overview of the installation of lightning protection

Constituent elements of protection

Lightning rod

The main task is to choose the right lightning rod, which should provide complete protection for the country house in its area of operation. Today, a pin, a mesh, a cable, or the roof itself can act as a lightning receiver. Let us consider in detail the features of the application of each of the options in a private house.

As for the pin, there are already finished products from manufacturers that have a suitable shape and convenient fastening. As a rule, the metal used to manufacture the lightning rod is copper, aluminum or steel. The first option is the most suitable and effective. In order for the receiver to do its job well, its cross section must be at least 35 mm2 (if copper) or 70 mm2 (steel rod). With regard to the length of the rod, in domestic conditions it is recommended to use receivers with a length of 0.5 to 2 meters. The pins are convenient to use in order to make a lightning rod on garden house, bathhouse or other small building.

The metal mesh can also be sold in already ready-made. As a rule, a mesh lightning rod is a cellular frame made of reinforcement, 6 mm thick. The size of the cells can be from 3 to 12 meters. Most often, this type of lightning protection is used in apartment buildings and large buildings, for example, shopping malls.

Rope is more practical at home and does the job better than mesh. To make a lightning rod in a private house with a cable, you need to stretch it along the roof (along the ridge) for wooden blocks as shown in the photo below. The minimum diameter of the cable for lightning protection of the building must be 5 mm. As a rule, this option is used if they want to make a lightning rod on the house with their own hands. slate roof.

Well, the last option - the roof as a receiver, can be used if the roof of a residential building is covered with corrugated board, metal tiles or other metal roofing material. With this type of lightning rod, two important requirements are imposed on the roof. First, the thickness of the metal must be at least 0.4 mm. Secondly, there should be no flammable materials under the roof. It is possible to make a lightning rod in a private house with a metal roof much faster and at the same time save on the purchase of special lightning rods.

Please note that if you use a mesh, its installation must be carried out at a height of at least 15 cm above the roof itself!

Down conductor

As a down conductor for a private house, a 6-mm wire made of copper, steel or aluminum is used. The wire must be connected to the lightning rod and the grounding system with bolts or welding.
The only, but very important requirement for the down conductor is that it must be isolated from environment and go to the ground along the shortest path. As for insulation, in dachas and country houses, the use of conventional cable channels is popular, which are also used if you need to make open wiring at home with your own hands

grounding conductor

Well, the last element of the lightning rod is the ground loop. In order not to make the material too voluminous, we have allocated a separate article for this issue - how to make grounding in a private house. We recommend that you familiarize yourself with the information so that you know all the subtleties of this stage.

In short, we can say that the ground loop should be located near the house, but not in the walking part of the site, but, on the contrary, closer to the fence. The discharge of the charge to the ground is carried out by metal rods buried in the soil to a depth of 0.8 meters. It is better to place all the rods according to the triangle scheme, which is just shown in the photo:

So, we got acquainted with the constituent elements of lightning protection on the roof, now we will consider how to properly make a lightning rod with your own hands.

Reliable lightning rod in the country - video tutorial on creating

Manufacturing instructions

To make it clearer to you how to assemble the lightning rod system of a private house into a single whole, we provide step by step instructions with photo examples:

Video instructions for assembling lightning protection by professionals

That's the whole technology of creating a lightning protection system. As you can see, it is not at all difficult to make a lightning rod in a private house with your own hands, the main thing is to correctly carry out the settlement work. We recommend that you definitely watch the video instructions, in which all the stages of installing a lightning rod are considered in more detail.

Lightning rod in the country. We make lightning protection with our own hands.

There is a widespread opinion that wooden house does not need lightning protection. Like, a tree is not a conductor, on the contrary, a dielectric, and the height of the roof is small, so a lightning rod is not needed in the country. Such misconceptions are deadly in the literal sense of the word, since lightning in dry weather is as rare a phenomenon as ball lightning. But in a thunderstorm, when it pours like a bucket, the conductor of electricity is not a tree at all, but water, which is life-threatening to attribute to dielectrics.

In these photos, the consequences of a rare phenomenon - a name for which we do not know. There was just a strong thunderstorm, and, despite the fact that the house is equipped with lightning protection, it was not it, but the perimeter of the roof spillway (it is metal) that acted as the discharge receiver circuit. All the machines turned off, but while this was happening, the author managed to take a few photos. This is a TV with a satellite dish, which is 2.3 m from the ground on the wall, and seems to be completely immune to lightning.

First the lightning introduced itself and showed itself
then lost with a TV picture.
After that, the picture disappeared, but the receiver was still alive, going into the factory settings mode.
After that, the house was completely de-energized, and how the matter would have ended remained a mystery. Photos were taken on a mobile, so as you understand, the process was not instantaneous. Get it, turn it on, take a picture, etc.

The receiver had to be repaired - it burned down, at the same time the usual antenna (meter range) suffered, and the spillway burned in two places. Three LED bulbs burned out. All incandescent lamps survived. There was no fire, no damage to the wiring either, thanks to correct connection grounding and lightning rod. So a lightning rod in the country is needed, since we know too little about lightning yet.

This was the preamble, and now about what and how you can do it yourself to avoid such cataclysms.

A bit of theory about the practice of lightning protection

We take pride in our practical knowledge of electricity, but we do not believe that scientists have already understood what lightning is - that is, the spontaneous discharge of atmospheric electricity. We also do not believe in the idea that clouds that “rub against each other” generate electricity. But we know that there are practical methods of protection, and they have long proved their effectiveness. We will focus on this aspect, taking a couple of laws of thermodynamics as a theoretical model, and also reading about a discharge in a saturated gaseous medium.

In this model, the discharge will occur between the point of greatest potential (somewhere in the clouds) and the nearest point of minimum potential. Note that this is exactly what happens in the vast majority of practical cases. Therefore, we take correct model lightning rod in the country house, a conditional point above the roof, which, being the top of a speculative hemisphere, will cover the whole house.

The radius of this hemisphere does not set the height of the country lightning rod, but the amount of potential that it is able to receive and give to the Earth (whose potential is relatively infinite). In fact, the radius of such a hemisphere is the depth of grounding, and it remains for us to understand how to choose materials in order to proceed to the task of how to make lightning protection with our own hands in the country.

Preparatory work in the arrangement of a lightning rod

The preamble tells about what can happen in a private house, which is equipped with a lightning rod, if two mistakes are made. The first is that the lightning rod receiver is next to the antenna, perhaps this had its effect. The second, more serious mistake was the constant cross section of the lightning rod channel throughout. Simply put, exactly the same strip goes from the metal strip of the receiver to the ground itself. All over the height.

The lightning receiver can be thin, its task is to cast a bait and wait for a bite. But the lower and closer to the ground the discharge discharge line, the “thicker” it should become. A very thick conductor must be buried in the Earth. That is, we go from the roof to the ground, increasing the cross section of the lightning rod.

So, we make lightning protection with our own hands in the country, without resorting to the help of specialists.

We determine the height and configuration of the roof, mentally covering it with a hemisphere from the top point of the lightning rod, which we make at our dacha.
The radius of the hemisphere is defined as a section of 5 sq. mm. 1 meter high. That is, a lightning rod in a country house 12 meters high (for a square house) should have a cross section of 12 x 5 = 60 square meters. mm. This is a strip 1 cm thick at 6 mm. Let us clarify that this is the minimum allowable value for the point at which the receiver tube will be welded to the discharge outlet channel. That is, the lower this tape goes down, the thicker it should be.
Determine the point of attachment of the lightning receiver pipe. Chimney not the best way- it is better to fix the pole on the wall, slightly increasing the height, than to allow a powerful discharge to hit the center of the roof. We dig a hole for grounding, most often triangular in shape, as well as for grounding.
We estimate the height of the pole, the depth of the pit and the cross section of the metal in the pit according to the principle - the more the better, but without fanaticism. If you make a pole too high and very good hole with grounding, then your dacha will collect all the lightning in the area on its lightning rod. Throw 10 percent on top - that will be enough.

Do not drive a few rebars into the ground! We dig a hole, weld several metal rods together, make sure that the welding is strong, cover the welding spots with protective compounds and then bury the hole.

Having finished preparatory work, we make lightning protection with our own hands:

We fix a metal bar on the pole. It is advisable to install a fan at the end (an old metal brush will do);
Using screw connections, after carefully cleaning the contact points, we connect the tape and the lightning rod;
We will make sure that both the lightning rod and the tape do not have contact with the roof - if necessary, we put insulators (they cost a penny and are screwed ordinary self-tapping screws);
We lower the tape along the wall to ground level and weld it to the ground loop. The place of welding is covered with protective compounds;
We check the absence of an adjoining of the tap tape to the wall, check the insulators, connections and dig in a hole with grounding;
In no case are we trying to save money and hang the electrical wiring ground on the same ground!

Our lightning rod in the country is ready. It remains to wait for the cataclysm to test it in action.

Some nuances of arranging a lightning rod in the country

Iron rusts for some reason, especially in the ground. It is possible to cover the ground with a protective compound, but it is more correct to take a thicker piece of iron. An angle 120x120 with a thickness of 12 will rust in the ground for 40 years without losing conductivity relative to the entire lightning protection circuit.

Additional impregnation of wooden walls with a flame retardant composition along the entire lightning rod line will be a very useful and not superfluous means of protection against fire.

Before choosing a specific location for a lightning rod in your country house, walk around and look at the tall trees and buildings around. The correct location would be where it is farthest from the nearest highest points. It's the farthest!

The whole complex of works can be done in a day, a maximum of two. This is not the most difficult task, it does not even require special knowledge. But it requires scrupulousness and thoroughness, so do it yourself, without involving mercenaries. You want to protect yourself, not to receive assurances that you are protected.

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Do-it-yourself lightning protection of a private house: materials, diagram, instructions

House and cottage Gardener's calendar June House and buildings DIY

Lightning strikes into unprotected private houses and trees, unfortunately, are not uncommon. The presence of lightning protection in the country is necessary - it will divert the discharge into the ground and help save your property, and sometimes life. We will tell you how you can make a lightning rod with your own hands, using improvised means and tools.

How to protect a private house from lightning

Lightning rod can be:

Rod - a metal pin fixed to the frame (on the roof, near the house, on a tall tree growing near the house). By means of a metal wire, the pin is connected to the grounding system. Such a lightning rod looks aesthetically pleasing, but its coverage area is not large. It is easy for them to calculate the protection area: from the highest point of the pin, you need to mentally draw a line to the ground at an angle of 45º. Everything that will be in the zone of the triangle along the perimeter is protected from lightning strikes.

Installation of rod lightning protection

Rope - its feature consists in several masts (two or four), interconnected by steel or aluminum wire. Such a lightning rod is more efficient and covers a large area with protection.

Cable lightning rod on the roof of a private house

These two types of lightning rods are the most common and are used in private houses and summer cottages, since their design is simple, and installation is not difficult to do with your own hands.

Lightning protection elements

Any kind of lightning rod system consists of three required elements:

Lightning rod. In a rod lightning rod, this is a pin fixed at least 1 m above the chimney, in a cable lightning rod, it is a wire connecting the masts on the roof. A metal roof can also act as a lightning rod if the coating thickness is 4-7 mm.
Down conductor is one of the main elements of lightning protection. It is a copper (d 16 mm²), aluminum (d 25 mm²) or steel (d 50 mm²) wire.
Grounding - a system of metal rods interconnected by a conductive material. It is located underground at a depth of at least 80 cm.

Materials and tools

To build lightning protection with your own hands, you will need:

The lightning rod is a pointed pin. A TV mast or radio antenna can be used, you can also buy a lightning rod from one of the leading manufacturers: SCHIRTEC, OBO Bettermann, J Propste, GALMAR;
Copper, aluminum or steel wire of the recommended section;
Pins, pipes or metal strips for grounding;
Mast (bed);
plastic mounts;
Tools (hammer, drill, shovel).

Installation of a wire lightning rod

At the first stage of installation of lightning protection, it is necessary to stretch the wire along the roof ridges, which will serve as a lightning rod.

Scheme of installation of a cable lightning rod

If the roof is covered with combustible materials (wood, plastic tiles), the wire should be at a distance of 10-15 cm from the surface on special plastic fasteners. The ends of the wire are attached to metal masts (horizontal lightning rods), or bent vertically.

Installation and fastening of the lightning rod

The down conductor is attached to the lightning rod by welding, bolts or rivets. Connection points are isolated. On the roof, the down conductor is fixed with brackets, on the walls of the house - with plastic fasteners. The wire can be placed in a cable channel to avoid the negative impact of atmospheric phenomena on it.

Down conductor from the roof of a private house

The grounding system is mounted at a distance of at least 5 m from the house, paths, benches. Nearby there should be no playgrounds for children's games and walking animals. Grounding works only in wet ground, which must also be taken into account when choosing a location.

Order of lightning protection grounding device:

Dig a trench to a depth where the soil is always damp (at least 80 cm)
Drive metal pins into the bottom of the trench.

Ground loop for lightning protection

Connect the pins together with a steel tape or pipe by welding.
Extend the grounding with a steel tape to the place of its connection with the down conductor.
Connect the down conductor to ground.

Fixing the down conductor to ground

Installation of a lightning rod

For a rod lightning rod, a high frame must be installed. Its role can be played by the mast of a television antenna. The rod lightning rod is attached to the mast by welding or bolts.

Scheme of a rod lightning rod in a private house

The installation of a down conductor and grounding of such lightning protection does not differ from that described above. After completion of work, it is necessary to check the resistance of the entire system. It should not exceed 10 ohms.

Service

Preventive maintenance of the lightning rod includes periodic cleaning of the rod pin from dirt, dust and oxide, as well as checking the integrity of all connections.

It is not difficult to independently mount a lightning rod in the country. If you follow all the recommendations and norms of the instructions for the lightning protection device RD 34.21.122-87, then in right moment it will work flawlessly.

Despite the fact that it is easy to make a lightning rod with your own hands, it is recommended to contact specialists to perform such work. Only professionals will be able to suggest which materials are better to use specifically in your situation, provide qualified assistance in choosing the right place for installation, and take into account the negative factors from which the protection may not work.

How to decorate a stump in the country with your own hands

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

Regulations

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 an effective lightning protection of a cottage, for example, should be provided for even at the stage of preparing a construction project. This approach to problem solving allows reliable system fire prevention, naturally integrated into the architecture of the building 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. About how to competently and without unnecessary problems to mount effective lightning protection with your own hands and will be discussed further.

What 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 of them:

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 building that is dilapidated and poorly protected from the effects of natural factors, the probability of its damage by a lightning discharge increases dramatically, which will require additional lightning protection devices from the owner.

Close location of high-rise objects

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

All of the listed high-rise objects are a good target for a lightning discharge and have the so-called "screen effect", which also includes a nearby residential building. 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 lightning protection, the protective effect of which is based on the discharge current draining into the soil.

In cases where the ground has low electrical conductivity in the country house or at the location of a country 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 to increase 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 of more than 40 hours per year, the risk of damage in this case will be maximum.

Lightning rod design

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

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

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

In this way, independent arrangement lightning rod for a private house involves the manufacture of the following mandatory elements of protection against thunderstorms:

pin or mesh type lightning rod;
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 to any high point on the roof in such a way 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 chosen as the 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 insulating supports as a receiver.

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

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 size of 2x30 millimeters.

During installation, they are laid along the walls of the building, and then welded on one side to the lightning rod, and on the other - to the ground loop, made according to the standard 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. At the same time, the lightning protection pin itself is securely fixed at the highest point of the structure (on a pipe or on a wooden antenna mast). If a grid is used, it is laid over the entire area of the roof with the formation of cells no larger than 12x12 meters in size (this value is selected based on the dimensions of the roof and the required quality of lightning protection).

At the intersections of the wires, the grids are fastened for welding, and then fixed on the roof of the house with the help of special holders, well isolated from the coating material.

Several contact pads are arranged along the lower edge of the grid, designed to connect the down conductor system (in standard project lightning protection is usually laid on two descents on each wall of the house).

The part of the grid structure of lightning protection 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 diversion device prepared in this way will provide high-quality lightning protection to any non-metallic roof of a private house.

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

The procedure for manufacturing a ground electrode

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

This requirement can only be met with a minimum electrical resistance the entire structure of the ground electrode, made from a set of metal blanks. As a rule, it is constructed from 3 thick steel bars or profiles at least 2.5 meters long, driven into the ground near the house (no closer than 5 meters).

These blanks are fixed in the ground in such a way that their tops form right 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 solid and reliable grounding structure.

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

Do-it-yourself lightning protection of a private house, country house and not only

Lightning protection advice from professionals

The destructive power of lightning is quite 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 bolts struck the same place within a second and a half. And hitting even a single lightning strike into a building without a lightning rod is enough for it to flare up like a candle. In spite of this, small house Lightning protection is pretty easy.

Above the roof ridge (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 the wooden bars, 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, a wire “plug” or a loop connected to the conductor. The same conductor descends along the wall of the house in the shortest way and is connected to the ground. If the length of such a lightning rod is more than ten meters, then it should be grounded from both sides.

Lightning most often strikes the ridges of roofs, the edges of gables, auditory and skylights. Therefore, the conductor can be laid in 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 paper and other combustible materials. Such a lightning rod is grounded at several points. wooden details painted with oil paint.

A house covered with iron will be completely safe if its roof is grounded three or 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. With a height of 5 m, counting from the ridge, it can protect a house 15 m long and 7 m wide. Install a lightning rod on a pole 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 near the house.

He is tied to the trunk over the branches 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 is flattened at the top or welded into a cone, and a loop is made from the wire, fixing its twisting or bandage of wire (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 to a depth of at least 80 cm (the deeper, the better). In the simplest case, a wire or a metal strip several meters long is laid in a ditch. You can drive two or three piles of 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 tire 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 grounding should be covered. 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 the paths and walkways.

The lightning rod is strengthened on wooden walls 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. The conductors must be laid in such a way that they do not have loops and sharp corners, otherwise they can be torn apart by the forces arising from a lightning discharge. At a height of about 2.5 m from the ground, they are covered with a steel pipe, a corner or a wooden box.

Methods for connecting lightning rod parts are shown in fig. 5. The most reliable are welding or soldering, but twisting, bandage connection, special clamps or overlap joints with bolts and rivets can also be used.

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

Every year, before the start 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, they check the serviceability of the connections, clean the contacts, tighten the weakened connections or replace them.

Once every five years, 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.