During a thunderstorm, most people flinch at the sound of thunder. In fact, the danger is not this sound, but a lightning strike. It is an extremely strong spark that travels several kilometers in the sky in a very short period of time. Since the speed of light significantly exceeds the speed of sound, a person first sees a bright flash, and only then does the sound of thunder reach him.

It is more correct to call a technical device that is designed to protect against lightning strikes not a lightning rod, but a lightning rod, but the first name is more euphonious. Essentially, a lightning rod is a long and pointed metal rod that is installed on the roofs of buildings. The lower end of the rod is connected to the surface of the earth. The principle of operation of such a device is based on the fact that a lightning discharge seeks to find a path. Lightning strikes the rod and, without any harm to other objects, travels through the wire into the ground.

Lightning is especially dangerous for those who stand in an open, level area during a thunderstorm. It would be a big mistake to hide from a thunderstorm under a lonely tall tree. It can just play the role of that very lightning rod, which lightning will certainly try to strike. It is also dangerous to use in open areas during a thunderstorm. mobile phone, since this electrical device is quite capable of receiving a lightning strike.

How does a lightning rod work?

It is generally accepted that the lightning rod was invented in 1752 by Benjamin Franklin. But there is also evidence that lightning diversion structures similar in appearance and purpose existed long before this. Most likely, the idea for such a device was found by chance, as is often the case with many useful inventions.

The operating principle of a lightning rod is quite simple to understand. You just need to understand that during a thunderstorm, large electrical charges arise on the surface of the planet, leading to the formation of a strong electric field. Its intensity is greatest near pointed conductors, where a so-called corona discharge can occur.

If a metal pin is installed on a building, charges do not have the opportunity to accumulate, and therefore a lightning discharge usually does not occur here. In those rare cases when lightning does develop, it strikes a metal rod, and the charge goes into the ground. In order for the lightning rod to be most effective, they try to place it as high as possible. The likelihood of an object being struck by lightning increases with upward movement. Raised to a sufficiently high height, the rod increases the area under its protection.

Good day, dear visitors of the project “Good IS!” ", section " "!

In today's article we will talk to you about lightning protection.

A thunderstorm accompanied by thunder and lightning - atmospheric phenomenon, which poses a great danger to people. Statistics testify to this - around the world, more than 3,000 people die from lightning strikes in 1 year! Material damage amounts to billions of dollars, because... The voltage of lightning is so high that when it hits the power grid, mountains burn various equipment and electronics.

Of course modern houses are built immediately with lightning protection, and there is nothing to worry about here, but what about in villages where few people paid due attention to this issue? Let's consider the issue of your and your home's safety, and if you still do not have lightning protection, we will install it. But first, a little theory about thunderstorms and lightning.

Thunderstorm theory

So, during a thunderstorm, the clouds are very strongly electrified relative to each other and the ground. In fact, the clouds and the ground during a thunderstorm are different poles, which can be considered different plates of a giant, constantly charging capacitor. And when the potential difference (voltage) reaches its peak, i.e. breakdown voltage between these “plates” (and these are billions of volts), then a lightning discharge occurs. Thunder is the acoustic derivative of a lightning strike.

What is lightning protection?

Lightning protection (lightning protection, lightning protection) – a set of measures and special devices to ensure the safety of the building, as well as the property and people in it.

The most simple solution Lightning protection is a lightning rod, or as it is also popularly called, a lightning rod.

Lightning protection comes in two types: external and internal systems lightning protection.

External lightning protection system

External lightning protection is a system that intercepts lightning and diverts it into the ground, thereby protecting the building (structure) from damage and fire. At the moment of a direct lightning strike on a construction site, a properly designed and constructed lightning protection device should absorb the lightning current and conduct it through down conductors to the grounding system, where the discharge energy should be safely dissipated. The passage of lightning current must occur without damage to the protected object and be safe for people located both inside and outside this object.

The following types of external lightning protection exist:

— A design where the lightning rod acts as a conductor between the plates of this capacitor (i.e., the capacitor is, as it were, short-circuited). Therefore, charge does not accumulate on its plates, and the capacitor is constantly discharged. And the tension in the area of ​​the lightning rod is practically zero. In other words, a lightning rod does not “catch” lightning, but creates conditions where lightning cannot occur. He simply “diverts” the lightning away from himself.

— A design where a lightning rod absorbs a lightning strike and releases all the voltage into the ground.

These 2 types are divided into the following types:

— lightning protection network;
— stretched lightning rod;
— lightning rod;
— active lightning protection.

In most cases, external lightning protection consists of the following elements:

— Lightning rod (lightning rod, lightning rod) is a device that intercepts a lightning discharge. Made of metal (stainless or galvanized steel, aluminum, copper)

— Down conductors (descents) - part of the lightning rod designed to divert lightning current from the lightning rod to the ground electrode.

— Ground electrode - a conductive part or a set of interconnected conductive parts that are in electrical contact with the ground directly or through a conductive medium.

Internal lightning protection system

Internal lightning protection is a set of surge protection devices (SPDs). The purpose of the SPD is to protect electrical and electronic equipment from overvoltages in the network caused by resistive and inductive connections arising under the influence of lightning current.

It is generally accepted that overvoltages are caused by:

— Direct lightning strikes. Such overvoltages occur when lightning strikes a building (structure) or communication lines connected to the building (structure) (power lines, communication lines). Overvoltages caused by direct impact are referred to as “Type 1” and are characterized by a waveform of 10/350 µs. They are the most dangerous because they carry a lot of stored energy.

— Indirect lightning strikes. These overvoltages occur due to shocks near a building (structure) or lightning strikes near utility lines. Depending on the type of hit, the overvoltage parameters also differ. Overvoltages caused by indirect shock are referred to as “Type 2” and are characterized by a waveform of 8/20 µs. They are less dangerous: the stored energy is approximately seventeen times less than that of Type 1.

History of lightning protection

It is believed that the lightning rod was invented by Benjamin Franklin in 1752, although there is evidence of the existence of structures with lightning rods before this date (for example, the Nevyansk Tower, Jacques Rom's paper kites).

A description of the first method of lightning protection appears in the annual Poor Richard's Almanac. “This is the way,” wrote Franklin. - Take a thin iron rod (such as nailers use, for example) long enough to lower three or four feet of one end into wet ground, and raise six or seven others above the highest part of the building. To the upper end of the rod attach a copper wire a foot long and as thick as a knitting needle, sharpened like a needle. The rod can be attached to the wall of the house with a twine (cord). On a tall house or barn, you can place two rods, one at each end, and connect them with wire stretched under the roof ridges. A house protected by such a device is not afraid of lightning, since the tip will attract it to itself and lead it along the metal rod into the ground, and it will not harm anyone. In the same way, ships, at the top of the mast of which a point with a wire will be attached, descending down to the deck, and then along one of the shrouds and plating into the water, will be protected from lightning.”

Every day about forty thousand thunderstorms occur on our planet, which are accompanied by atmospheric electrical discharges - lightning. This natural phenomenon can seriously harm a person, even if at that moment he is in a closed building - when there is no lightning rod there.

When lightning strikes such a structure, the electrical discharge goes into the ground through plumbing systems and electrical wiring. Consequently, not only the equipment connected to the network at this moment is in danger, but also the life of a person, who can receive a severe electric shock that can be fatal.

To prevent such unpleasant consequences, you need to know how a lightning rod (in other words, a lightning rod) is designed, as well as where and how it should be used.

What is a lightning rod (lightning rod)

A lightning rod for a residential building or other type of building is a system that allows the resulting electrical charge to be discharged directly into the ground, bypassing contact with the most important elements object.

Main types of lightning rod systems:

Initially integrated option. Installation of a lightning rod of this type is carried out directly at construction work, and its constituent parts are some elements of the object being built.

External option. Installed after completion of construction.

How does a lightning rod work?

The lightning rod system is a structure of three main parts:

A metal component that is placed directly into the ground.

A structure (steel rod, wires, cables) that absorbs a lightning strike on the roof of a building. Always located above level extreme point object.

A connecting metal cable through which the discharge will flow into the ground, bypassing the building.

Methods for manufacturing lightning rod structures:

Using one of the types of welding work.

Other methods of fastening system elements are riveting, pressing, clamping, and so on.

The presence of everything necessary to carry out such work allows the company’s employees not only to create guaranteed reliable protection systems, but also to aesthetically integrate them into the exterior of the building with high quality, even if it is decorated using large number various materials.

The Alef Em company guarantees its customers quality and compliance with all manufacturing standards. Minimum values ​​of conductive elements:

When using copper minimum size material is 35 mm².

For aluminum - 70 mm².

For galvanizing - 50 mm².

The manufacture of lightning rods, as well as their installation, should be carried out by experienced specialists, since the lack of necessary knowledge can lead to errors in calculations. And this is the probability of all or part of the discharge entering the building systems that must be protected. It is especially important to have the necessary experience when creating a lightning rod for wooden house, where incorrect calculation can easily cause a fire.

Alef Em company: quality from professionals, prices for everyone

The Alef Em company is a professional in the field of lightning protection. Specialists high level will perform an accurate calculation of the lightning rod, and will also reliably install the structure on any type of building.

Our prices are affordable and our results are long lasting. Therefore, if you set out to buy a lightning rod in Moscow, feel free to contact us - we will take into account all your wishes and select the best option for protecting your building from lightning.

There is no price list for lightning rods as such, since each order is individual, and the price of any design depends on many factors: the conductor used, the external dimensions of the structure, the materials used in its construction. Our catalog contains prices for components of lightning protection systems.

Frequently Asked Questions

1. What is the operating principle of a lightning rod?

Because lightning is a very large release electrical energy, produced by nature itself, then its redirection away from a residential building or any other building that needs to be protected can be ensured through the simplest physical laws.

Because this is electricity in pure form, then it is transmitted through the circuit that has the least resistance. A lightning rod is designed precisely according to this principle and appears to lightning as a suitable circuit for transmitting electric current. Thus, he takes the blow and deposits the resulting discharge into the ground, helping to save the house, electrical appliances, etc.

2. Does a roof covered with metal really not require additional installation lightning protection?

In fact, the answer to this question follows from the same elementary physical laws. Self metal coating acts as a circuit with low resistance, but if other protruding elements not made of metal are installed on it, then they must be provided with high-quality protection from the elements.

3. We were offered to install a separate lightning rod. What is its fundamental purpose?

The main and fundamental task of this type of lightning rod is to protect a building or a complex of buildings from the rapid transmission of lightning current received from a discharge through any metal structures the object itself. The impulse is taken over by a free-standing structure. In order to achieve this effect, when installing special attention is given to the distance to buildings, taking into account both ground and air distances.

4. Does a house near a pond, tall trees or with a soft roofing need a lightning rod?

Yes, of course, but not only in the lightning rod, but also in the internal lightning protection system. Strictly speaking, any house is a kind of magnet that attracts a discharge, since its foundation is installed in the ground. Also influenced by the presence of wires for supplying electricity, they are grounded to avoid electric shock to humans. A nearby lake or other large body of water increases the risk of a direct lightning strike. Tall trees located close to the roof, even if it has a non-metallic covering, have the same effect.

Sudden power surges caused by lightning striking a power line directly are also very dangerous. Such jumps can lead to short circuit and fire, burnout of electrically powered equipment and household appliances. That's why it's worth paying attention to internal protection.

Country houses are usually built from flammable materials, and the fire station is located far away. Yes, and you can’t drive up to every building, and you shouldn’t expect anything good from the strong wind that accompanies any thunderstorm.

Sometimes from a lightning strike Entire holiday villages are burning down.

We’ll tell you how to make an effective lightning rod on your own and eliminate the risk of a direct hit from a “heavenly discharge” into your house.

In simplified terms, the physics of the process can be described as follows: source lightning are cumulonimbus clouds.

During a thunderstorm, they turn into peculiar giant capacitors. On the upper plus part, a huge positively charged ion potential accumulates in the form of ice crystals, and in the lower minus area, negative electrons accumulate in the form of water drops.

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

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

The idea of ​​a lightning rod is to install it near the house area of ​​minimum resistance so that the lightning discharge passes through it and not through the structure.

If you don’t have a lightning rod at your dacha, it’s time to think about building one. 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, ensuring the safety of the building and people's lives, located in it, from the destructive influences that may arise during a thunderstorm when direct hit lightning.

This corrosion protected, bare conductor - that is, a well-conducting material with as large an area and a larger cross-section as possible (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, angles, strips, and so on.

It is better to use galvanized steel materials. Since they are less susceptible to air oxidation.

What does lightning protection consist of: device

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

(descent).

Let's talk about each element in more detail.

A metal conductor mounted on the roof of a building or on a separate support (tower). Structurally divided into three type: pin, cable And mesh.

When choosing a lightning rod design focus on the material, which covers the roof of the house.

1. Shtyrevoe(or rod) lightning rod device is a metal vertical rod rising above the house (see figure below).

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

Materials for production:

Steel pipe (20 -25 mm diameter, with wall 2,5 mm thick). Its upper end is either flattened or welded into a cone. You can also make and weld a special needle-shaped plug to the upper edge of the pipe.

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

Any steel profile (for example, angle or strip steel of at least 4 mm in thickness and 25 mm in width).

The main condition for all these steel materials is the cross-section minimum 50 mm².

2. Trosovoye the lightning rod device is stretched along the ridge at a height of up to 0,5 m from the roof cable with a minimum cross-section 35 mm² or wire.

Galvanized steel rope is usually used. This type lightning rod is suitable for wooden or slate roofs.

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

3. Mesh the device of the lightning rod system is a mesh laid over the roof with a thickness 6 -8 mm. This design is the most difficult to implement. Used for roofs covered with tiles.

4. Well, it’s very rarely used covering device lightning protection is when metallic lightning rods act as lightning rods structural elements the house itself (roof, trusses, roof railing, drainpipe).

All considered designs of lightning rods securely connected by welding with a down conductor and through a down conductor with a single- or double-sided grounding conductor welded seam minimum 100 mm in length.

(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.

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

Ideal path for electric current to pass- the shortest straight line directed straight down. Avoid turning at sharp angles when installing the lightning rod. This is fraught with the occurrence of a spark discharge between nearby sections of the down conductor, which will lead to inevitable ignition.

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

Minimum distance from the wall to the down conductor 15-20 cm.

It must be laid out so that there were no points of contact with elements of the house such as a porch, front door, window, metal garage doors.

We know that It is better to connect parts of a lightning rod by welding, but if this is not possible, it is allowed to interface the down conductor with the grounding conductor and lightning rod using three rivets or two bolts. The length of application of the current conductor to other parts of the system with a rivet connection is equal to 150 , and with a bolted one - 120 mm.

The end of the non-galvanized wire rod and the place where the wire conductor is attached to steel parts to ensure reliable contact needs to be cleaned, and it is enough to wash the galvanized one from dust and dirt. Then a loop or hook is made at the end of the wire, washers are placed on both sides and the whole thing is tightened as tightly as possible with a bolt.

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

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

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

How to properly arrange grounding is described in GOST oh and SNIP ah, but for the most simple option it is enough to have at least one meter from the edge of the foundation and no closer 5 meters from the entrance to the building to bury P-shaped structure made of metal conductors.

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

This 3 electrodes driven and buried in the ground, connected to each other at the same distance by horizontal ground electrodes. The grounding structure should be buried below the maximum soil freezing level. From 0,5 to 0,8 meters deep.

For a grounding conductor take rolled steel cross section 80 mm, less often copper cross-section 5o mm squared. Vertical grounding electrodes are 2-3 meters long, but the closer the level groundwater, the shorter they are.

If the soil at your dacha is constantly wet, then a meter or half meter pin will be enough.

On what depth to drive and how many electrodes will be necessary can be found in energy service at your 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 resistivity the soil itself.

Grounding conductor for lightning rod need a separate one, you should not ground the lightning rod to the household circuit. Categorically We do not recommend experimenting. It is fraught with consequences.

We invite you to watch the video from visual diagram installation of lightning protection:

According to regulatory documents, installation of lightning protection systems for private residential buildings optional. And only you can decide the feasibility of installing a lightning rod (lightning rod) at your dacha. We hope that the article will help you make the right decision.

If we look at the statistics dead people from lightning strikes, this number is greater than the number of victims in plane crashes. Every year, lightning claims several thousand lives and also causes millions of dollars in property damage. Every dacha owner or own home knows that only you can protect your property and relatives yourself. Therefore, it is better to make lightning rods yourself.

Homemade lightning rods work normally, which is confirmed in practice. Such devices have another name - lightning rods. Thunder does not cause any harm other than the loud sound. And to protect against lightning it is necessary to build some kind of structure.

A lightning strike usually strikes a structure with the maximum height it encounters in its path. Dangerous place during a thunderstorm there is a residential building or other building due to the presence of metal elements– roof, television antenna, etc. Residents of city apartments need not worry, as most multi-storey buildings already have lightning rods.

If there is a cell tower near the house, then there is no need for a lightning rod. In all other cases, it is still advisable to secure your home. If you call specialists for such work, it will cost you a lot. But if you understand the design of the lightning rod system, you can do everything yourself.

Types and features of the device

The figure shows the structure of the lightning removal system.

There are several types of lightning rod, but their main parts are the same:

• Lightning rod.
• Current dissipation device.
• Grounding.

Types of lightning rods

The top of this protective system called a lightning rod.

• Rod the lightning receiver is pointed at the end. It is struck by lightning during a thunderstorm. The best option manufacturing of the lightning receiver is a copper pin with a diameter of 15 mm. It should be located high enough, but a receiver that is too high will attract lightning electrical discharges. Rod lightning rods are the most aesthetically pleasing, unlike cable lightning rods, but they provide a smaller protective radius in the area. The size of the protected space depends on the height of the metal pin.

• Cable The receiver is capable of protecting a large area of ​​the site, in contrast to a rod lightning rod. Cable structures are used in power line devices. Instead of metal pins, they use a cable that is connected to other elements with a bolted connection.

• Mesh receiver zippers are made in the form metal mesh on the roof of the house.

Down conductors

The next part of the lightning removal system is a down conductor, consisting of thick ones, secured with special couplings to the lightning receiver and the ground loop. Plastic fasteners are used to mount it on the wall. The down conductor must be isolated from exposure external environment. For this, plastic is usually used.

Grounding

The main grounding elements are located in the ground. The ground electrode consists of metal rods welded together or bolted together.

Grounding the lightning removal system is an important part of the entire structure. This grounding loop is similar to the grounding device for a house. An important requirement here is that these two different ground loops must not be connected under any circumstances. Otherwise, during a thunderstorm, household electrical devices may fail, or a wooden house may catch fire from a lightning strike.

Requirements for grounding the lightning removal system:

• Metal pins inserted into the ground must be at least three meters long.
• The cross-section of metal pins is at least 25 mm 2.
• The pins are connected to each other by a triangle, which is different from the usual grounding of the house.
• There should be a distance of at least 3 meters between the vertices of the triangle.
• As connecting bars, it is allowed to use a metal rod with a diameter of at least 12 mm or a strip with a cross-section of 50 x 6 mm.
• The length of the welds should not be less than 20 cm.
• For grounding lightning rods, a minimum depth above the ground surface of 50 cm is established.

Grounding location

This issue should be approached with the greatest attention and accuracy. Grounding electrodes should not be installed in areas where animals are located, or near playgrounds. Also, these elements should not be placed near benches or paths.

Grounding will work better in damp soil. To maintain the functioning of the grounding, you can independently create the conditions for this by periodically watering the grounding site with water. If there is no possibility of watering this place, and the soil in your area is too dry, then it is recommended that when installing grounding electrodes in the soil, sprinkle them with a mixture of salt and charcoal.

How lightning rods work

To understand the principle of operation of a lightning removal system, you should imagine a large capacitor that is constantly charging. Its covers will be clouds and earth. When a thunderstorm occurs, the plates of this large capacitor begin to become electrified among themselves and accumulate a charge. When the voltage difference between the plates reaches equal to the lightning breakdown voltage, a strong lightning discharge occurs, reaching several billion volts.

To prevent charge from accumulating, it is necessary to short-circuit this capacitor to ground. Lightning rods are such a closing conductor. Therefore, during a thunderstorm, the capacitor is discharged and the plates cannot accumulate charge, and the voltage in the lightning rod decreases to zero. In other words, the lightning discharge system creates conditions in which an electric lightning discharge cannot occur, since the accumulated charge is discharged into the ground.

Peculiarities self-installation lightning rod

• It is recommended to make lightning rods from materials that are not subject to corrosion. For this, a galvanized corner, tinned sheet metal, a duralumin profile, or a mesh made of bare copper wire are used. The connecting conductors must have the required cross-section. The lightning rod must not be covered paint and varnish materials or other insulation.
• For convenient location As a lightning rod, you can use a tall tree located near the house. In order not to cause harm to the tree, the lightning receiver can be mounted on a long wooden pole, which is fixed to the tree with the help of, and placed at the maximum height.
• If there is no tree, then you can use a television antenna, which is mounted on the roof of the house, to attach the lightning rod.
• Another installation method is chimney, to which you can attach a metal pin and connect it to ground.

Maintenance

In order for the lightning rod system to work flawlessly, it is necessary to maintain its structure to maintain it in working condition. The metal pin, which acts as a lightning receiver, must be cleaned with conventional cleaning agents such as sandpaper or other similar means to prevent oxide formation and remove contaminants.

In dry times, it is necessary to periodically moisten the soil in the area where the ground loop is laid.