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

It is known from the school physics course that lightning is a huge electrical discharge, which carries a large thermal energy in itself. The consequences of a lightning strike can be catastrophic, therefore at all times mankind has tried to create devices and devices that would protect them from this natural scourge. In the modern world, lightning protection of a private house is a combination of structural features of a building and special devices designed to drain 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 first goal 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 house's internal electrical wiring. In this case, high overvoltages arise in the internal wiring. The consequence is the failure of most of the 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 on wooden floors or the house was wooden.

This problem can be solved by installing special devices in the electrical network that will protect it from surges. For example, surge arresters, all kinds of arresters, SPDs (surge protection devices). All devices are installed in the distribution board 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 their reliable connection to each other. Different types of lightning protection must be used depending on the roofing material. There are three of them: pin, cable and mesh.

Pin

It is usually used if the roof of the house is covered with metal roofing material. For example, metal, 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, about 1-2 m higher. This will be the lightning rod. It can be made 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 strikes of the elements 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 carrying capacity of a lightning rod is not based on the size of the area that it covers. If we take into account that the vertical line of the pin is the height of the isosceles triangle, then the base of this figure will be two heights. It turns out that a circle with a radius equal to the height of the pin installation can form on the ground surface.

Rope

For this lightning rod, a cable is required, which is pulled over the ridge of the roof, and it is suspended at a height of half a meter above the level of the ridge installation. For this, it is best to use a galvanized wire rope with a total minimum cross-section of 5-7 mm. This lightning protection is used if the roof of the house is covered with slate.

The cable is pulled along the ridge and attached to the wooden posts installed along the edges of the ridge bar. If the roof is long, then there may be more racks, the main thing is to observe a small slack in the cable. Strong sagging is unacceptable, because this reduces the distance from the roof ridge to the air terminal. 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 sophisticated structure that is installed on roof tiles. Making such a lightning rod with your own hands is not easy. For this, steel wire rod with a 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 mesh sizes of 6x6 m and more, it all depends on the roof area. All connections are welded, fastened to the roof with staples.

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

Requirements for the down conductor.

1. This should be the shortest path from the lightning rod to the ground loop.
2. Do not use bends and creases when laying, which will become a place for the appearance of a spark charge in the process of removing electricity, leading, as practice shows, to ignitions.
3. The route of laying is chosen so that the wire does not pass near windows and doors.
4. If a lightning protection device for a wooden house is being made, the down conductor is installed at a distance of 15-20 cm from the surfaces of the wooden structure. For this, special brackets are used. They are in the form of a metal clip, the base of which is made of hard and durable plastic. It is the plastic that protects the conductive element from contact with the wooden structures of the house. The bracket is attached to 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.
5. 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 CO 153-34.21.122-2003).
6. Wire rod is carried along the walls of the building, along the pediments and sharp ledges of the roof. That is, in those areas where lightning can strike.

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, sites, trenches are dug in the shape of an equilateral triangle. Trench depth - 80 cm, width - 60 cm, length 1.5-2 m.
• At the corners of the triangle, pins from a steel corner with dimensions of 50x50x5 mm are driven in. The depth of penetration is 2-3 m.The corners should not be completely hammered into the ground, the height of the free protruding segment is 20-30 cm.
• The pins are connected to each other by a steel strip 4 mm thick and 40 mm wide. You can use the same corners for these elements as for the pins.
• This grounding circuit of the lightning protection is connected to the down conductor.

Attention! All connecting joints must be electrically welded. Bolted connections are not welcome, because during the operation of the lightning rod of a country house, they can weaken, rust and weaken the conducting capacity of the entire structure.

DIY assembly

Before making a lightning rod in a private house, you need to decide which type of lightning rod to choose. If this is a pin version, 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 the two segments using an aluminum or copper contact, which is used in overhead power lines. 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 special devices on bolted connections made of non-ferrous metal are used as a connection.

Attention! The best option is if the grounding and lightning protection circuit is located close to each other and connected to each other with a wire rod or strip. This does not violate the norms of the lightning protection device, moreover, 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 an element of security not only for the building, but also for the people living in it. Therefore, you should not postpone its installation indefinitely. The ideal time for installation is building 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 reasons for the phenomenon. This will allow you to better understand all actions and possible consequences in case of violations of the developed instructions.

Thunder - air waves that appear due to a sharp increase in air pressure after a lightning strike contact. The current strength in lightning can reach 500 thousand amperes, and the voltage is several million volts. Such a powerful eclectic discharge causes air to heat up to high temperatures, and its volume increases sharply. As a result, sound waves from lightning appear, which are called thunder. Thunder is a consequence of lightning and does not pose any danger to the house; buildings must be protected 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 competent developers think that a metal pin attached to the ridge of the house will attract all lightning bolts along a cylindrical circle above it and lead them to the ground along a 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 into the ground near the house and tied to a bar on a ridge will not bring any benefit. Why?

1. Where can you find a wire that would withstand a current of 500,000 A and a voltage of 1,000,000,000 V? This is exactly the kind of discharge that lightning has when it meets the ground.
2. Why, in principle, attract lightning and guide them along the wire, risking igniting the structure due to overheating of the down conductor?
3. What to do if there are several buildings of different storeys in the summer cottage? Do you have to make a lightning rod system for everyone?

Output. 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 hitting the structure.

These are very complex calculations, simplified formulas give a big error. Sometimes it is not possible to fulfill the initial technical conditions, there may be several reasons, some of them are objective and do not lend themselves 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 unite and form step leaders. It is they who shine brightly and are rapidly heading towards the ground.

As we approach, the voltage of the eclectic field on the ground increases, all electrons in it rush upward and, at the highest point, throw out a reciprocal streamer towards it. It connects to the leader, the circuit closes, the electrical discharge goes into 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 install lightning rods on the house.

1. If the earth in a given 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 old-timers. If they cannot remember the cases of lightning striking any objects, then there is no need to mount a lightning rod.
2. The house is located on land that can accumulate a charge, lightning strikes in this area are not uncommon. The installation of a lightning rod is mandatory, but you must strictly follow the installation rules and perform preliminary calculations.

How does a lightning rod work

An effective lightning protection system aims to minimize the direction of lightning step leaders into the building area. And for this there is only one condition - the electric potential of the land in this area should be minimal and necessarily much less than on the neighboring ones. This task must be performed by lightning rods. They constantly, and not only during a thunderstorm, direct electric charges into the atmosphere and thereby significantly reduce the voltage potential. The conditions for the appearance of oncoming streamers disappear, the lightning finds other points of energy drainage.

Important. If lightning has hit the lightning rod, it means that it is not mounted correctly and instead of good it brings harm.

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

Now that the principle of operation of the lightning rod is clear, the tasks of each element of the system are clear, you can start installing the protection of the house.

Step-by-step installation instructions

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

It is recommended to go to work only after calculating the number, size and location of ground electrodes. Only qualified specialists can perform such calculations. By the way, they must, after installation, check the efficiency 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.Fold back 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 the skates of various sizes, while the reliability of fastening is maintained throughout the entire period of operation, spontaneous unscrewing is completely excluded.

Step 2.Fasten the holders of the down conductors to the ridge. If you buy an industrial-made lightning protection system - great, it has all the elements you need to install the equipment. You can make them yourself, but this will take additional time. In addition, handicraft holders are significantly inferior in design and do not decorate the building in any way.

The distance between them is about one meter, it is necessary to ensure that the wire does not touch the roof covering. Try to fasten at the same pitch, so the system looks much better and does not negatively affect the appearance of the house.

Practical advice. Always work with a safety rope on roofs, especially for metal surfaces. If it is not possible to purchase industrial equipment for climbers, then make the elementary ones yourself.

Tighten the lugs (nuts) firmly, use open-end wrenches or pliers. Remember that it is difficult to correct the mistake later, you will have to climb onto the roof again. Make sure that all vertical wire posts are in line.

Step 3.Begin 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, thereby significantly improving performance.

1. The wire will not rust and brown streaks will not appear on the roof. Traces of rust greatly impair the appearance of the building.
2. Due to the fact that the wire does not rust, the resistance indicators remain unchanged for a long time. And this is a very important parameter of any lightning rod.
3. At the junction points, the resistance decreases; during operation, it does not deteriorate the physical and electrical characteristics.

You should not save 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 nippers.

Step 5. Spread the threaded connections with special mastic, if it is not there, then you can use ordinary grease. Mastic additionally protects metal surfaces from oxidation. The fact is that while tightening the nuts, the zinc on the thread breaks off due to strong friction, and the metal requires protection for openings.

Step 6.Proceed to fasten the wire on the ramps in the longitudinal direction. Here, the installation technology depends on the type of roofing material.

1. Single wave metal roof tiles. It is necessary to release the screws a little, lift the sheet and insert the mounting bracket into the gap formed. It has a curved leg that fits 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 the tabs.

   

   

   

2. Piece tile. There are special brackets for such a roof, 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, thereby increasing the strength of the fastening. Then you should raise 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.

   

   

   

   

3. Sheet metal roof tiles. For fixing 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 self-tapping washer.

   

   

   

   

   

4. Flexible bituminous shingles. This roof covering has a solid base, which makes it much easier to fix the brackets. They are screwed to the surface with ordinary wood screws; rubber pads 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 ramp to the rear. It is recommended to connect them at the intersection with the ridge wire; use elements with bolted tightening for this. Thus, you will achieve reliable contact of the down conductors.

Prices for holders for down conductors

Holders for down conductors

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

Down conductors installed on the house are connected to the ground.

Manufacturing grounding

This is the most important element of a lightning rod, as already reported above, only a specialist with 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 for the manufacture of metal pins, the distance and quantity, and the depth of burial for each ground are selected. Depending on the size of the house, a specific location of ground electrodes is selected.

Voltage stabilizers prices

Surge Protectors

1. For steel pins, the cross-sectional area must be at least 80mm2, for copper pins 50mm2. It must be remembered that both steel and copper oxidize at different rates, and oxides negatively affect the current conductivity. The cross-section and surface area of \u200b\u200bthe rods must be selected with a margin, and resistance measurements should be made annually. When critical values \u200b\u200bare reached, it is recommended to dig out the rods and clean them from rust.
2. 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 soils; decisions are made by a specialist at the place of work.
3. All ground connections are best done by welding, the clamps quickly lose their initial resistance values. Welding is done on both sides, the seam length is at least five centimeters.
4. Professionals advise using a metal strip with a thickness of at least 1 mm and a width of about three to four centimeters instead of round pins. Such metal is not only cheaper, but also significantly increases the operating time of the lightning rod due to the large area of \u200b\u200bcontact 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 a large number of people. There are no exact statistics on the system's performance, no one knows how many lightning strikes were taken away from the building and what is the efficiency of the device.

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 need to carefully analyze all the factors that affect the likelihood of a lightning strike in 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 meet the existing building codes.

Video - Installation of a lightning rod

Country houses are usually built of combustible materials, and the fire station is far away. And you can not drive up to every building, and you should not expect anything good from a strong wind that accompanies any thunderstorm.

Sometimes whole summer cottages burn out from a lightning strike.

Let's talk about how to make an effective lightning rod on our own and minimize the risk of a direct “heavenly discharge” hitting a house.

Where lightning bolts come from

Simplistically, 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 plus part in the form of ice crystals, and negative electrons in the form of water drops are collected in the lower minus area.

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

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

DIY lightning rod

The idea of \u200b\u200ba lightning rod is to equip a section of minimum resistance near the house so that the lightning strike passes through it, and not along the structure.

If you do not have a lightning rod at 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 device (lightning protection) 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-resistant, bare conductor - that is, a highly conductive material of the largest possible area and a large cross-section (minimum 50 mm²).

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

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

What lightning protection consists of: device

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

Lightning rod.

Down conductor (descent).

Earthing switch.

Let's talk about each element in more detail.

Lightning rod

A lightning rod is a metal conductor fixed on the roof of a building or on a separate support (tower). Structurally, it is divided into three types: pin, cable and mesh.

When choosing the design of an air terminal, be guided by the material that covers the roof of the house.

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

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

Materials for making:

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

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

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

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

2. A catenary wire device of an air terminal is a cord with a minimum cross-section of 35 mm² or wire stretched along the ridge at a height of up to 0.5 m from the roof.

Galvanized steel rope is commonly 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 using ram clamps.

3. The mesh device of the air termination system is a 6-8 mm thick mesh laid over the roof. This design is the most complex in execution. Suitable for roofs covered with tiles.

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

All considered designs of lightning rods are reliably connected by welding with a down conductor and through a down conductor with a ground electrode with one or two-side welded seam 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 electric current to flow is the shortest straight line straight down. When installing the lightning rod, avoid sharp turns. This is fraught with the occurrence of a spark discharge between closely spaced sections of the down conductor, which will lead to inevitable ignition.

The most popular material for down conductors is uninsulated steel wire rod or strip. It is carried out only on non-combustible surfaces. Metal brackets should be installed on combustible walls, which themselves, being in contact with the 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, 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 pair the down conductor with a ground electrode and an air terminal using three rivets or two bolts. The length of the overlapping of the down conductor on other parts of the system with a riveted connection is 150, and with a bolted one - 120 mm.

The end of the non-galvanized wire rod and the place of attachment of the wire down conductor to the steel parts must be cleaned to ensure reliable contact, and the galvanized wire must be cleaned of dust and dirt. Then a loop or hook is made at the end of the wire, washers are placed on both sides and they are tightened as tightly as possible with a bolt.

In addition, the joints (if this is not welding) must be wrapped in several layers with electrical tape, then with a coarse cloth, twisted over with a thick thread and cover everything with paint.

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

Earthing switch

Earthing switch (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, at least one meter from the edge of the foundation and no closer than 5 meters from the entrance to the building is enough to bury a U-shaped structure made of metal conductors.

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

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

For the earthing switch, rolled steel with a cross section of 80 mm is taken, less often copper with a cross section of 5o mm squared. Vertical grounding 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 in a wet state, then a meter or half meter pin will be enough.

To what depth to drive in and how many electrodes will need to be found 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 \u200b\u200bthe ground electrode system with the soil and the specific resistance of the soil itself.

The grounding conductor for the lightning rod needs a separate one; the lightning rod should not be grounded to the household circuit. We strongly advise against experimenting. Fraught with consequences.

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

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

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Protecting a private house from lightning - an overview of a good lightning rod

A reliable lightning rod at 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. A good lightning protection system consists of an earthing switch, a down conductor and a lightning rod. Next, we will tell the readers of Electrica Sam about what all the elements of the system should be and how to make a lightning rod in a private house with your own hands!

How the system works

To begin with, let's figure out how 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, metal rods on the roof are lightning rods that discharge a dangerous discharge to the ground through a down conductor and a special grounding.

There is an opinion that if a telephone tower is installed next to the house, it is possible not to make a lightning rod in a private house. This is wrong, because it is better to spend a little time and ensure yourself complete protection from lightning strikes. So that you know what a lightning rod should be and how to make it correctly with your own hands, below we will separately consider the specifics of choosing each of the system elements.

Brief overview of lightning protection installation

Component elements of protection

Lightning rod

The main task is to choose the right lightning rod, which should provide full protection of the country house in the area of \u200b\u200bits action. Today, a pin, mesh, cable or the roof itself can act as a lightning receiver. Consider in detail the features of using each of the options in a private house.

As for the pin, there are ready-made products from manufacturers that have a suitable shape and convenient attachment. As a rule, the metal of the lightning rod is made of copper, aluminum or steel. The first option is the most appropriate 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 a garden house, bathhouse or other, small building.

The wire mesh can also be sold ready-made. As a rule, a mesh lightning rod is a mesh frame made of reinforcement, 6 mm thick. The mesh size 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 centers.

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

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 tile or other metal roofing material. With this version of the 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

A 6 mm copper, steel or aluminum wire is used as a down conductor for a private house. The wire must be bolted or welded to the lightning rod and grounding system.
The only, but very important requirement for the down conductor is that it must be isolated from the environment and pass 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 in the house with your own hands

Earthing switch

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 question - 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 next to 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 pattern, which is exactly shown in the photo:

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

Reliable lightning rod in the country - video tutorial on creating

Manufacturing instruction

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

Video instruction on lightning protection assembly by professionals

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

Related materials:

samelectrik.ru

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

There is a widespread belief that a wooden house does not need protection from lightning. They say that a tree is not a conductor, on the contrary it is a dielectric, and the height of the roof is not high, so a lightning rod is not needed in the country. These kinds of delusions are literally deadly, since lightning in dry weather is as rare 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 dangerous to life as a dielectric.

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

First the lightning presented itself, and showed itself,
then played with a TV picture.
After that, the picture disappeared, but the receiver was still alive, having switched to the factory setting mode.
After which the house was completely de-energized, and how the matter would have ended remained a mystery. The photos were taken with a mobile phone, so as you can imagine, the process was not instant. Get it, turn it on, take a picture, etc.

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

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

A little theory about the practice of lightning protection

We are proud of our practical knowledge of electrical engineering, but we do not believe that scientists have already understood what lightning is - that is, a spontaneous discharge of atmospheric electricity. We also don't believe in the idea that electricity is generated by clouds that "rub against each other". But we know that there are practical methods of protection, and they have long proven 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 gas environment.

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

The radius of this hemisphere is determined not by the height of the dacha lightning rod, but by the volume 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 grounding depth, and it remains for us to understand how to choose materials in order to move on 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 gave its effect. The second, more gross mistake, was the constant cross-section of the lightning rod channel along its entire length. Simply put, exactly the same strip goes from the metal strip of the receiver to the ground itself. Across the entire height.

The lightning receiver can be thin, its task is to throw a fishing rod and wait for a bite. But the lower and closer to the ground the 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 section of the lightning rod.

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

1. 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.
2. The radius of the hemisphere is defined as a section of 5 sq. Mm. 1 meter in height. That is, a lightning rod in a dacha with a height of 12 meters (for a square house) should have a cross section of 12 x 5 \u003d 60 sq. mm. This is a 1 cm strip with a thickness of 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.
3. Determine the attachment point for the lightning receiver pipe. A chimney is not the best option - it is better to fix the pole to 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 of a triangular shape, as well as for grounding.
4. We estimate the height of the pole, the depth of the pit and the section of the metal in the pit according to the principle - the more the better, but without fanaticism. If you make too high a pole and a very good pit with grounding, then your summer cottage will collect all lightning in the area on your lightning rod. Throw 10 percent on top - that will be enough.

Don't drive a few fittings into the ground! We dig a hole, weld several metal rods together, make sure of the strength of the welding, cover the welding spots with protective compounds and then bury the hole.

Having completed the preparatory work, we do 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);
• With screw connections, after thoroughly 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 with ordinary screws);
• We lower the tape along the wall to ground level and weld it to the ground loop. We cover the welding place with protective compounds;
• We check that the tap-off tape does not adhere to the wall, check the insulators, connections and bury a hole with grounding;
• In no case are we trying to save money and hang the ground of the wiring on the same grounding!

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

Some of the nuances of arranging a lightning rod in the country

Iron for some reason rusts, especially in the ground. It is possible to cover the grounding with a protective compound, but it is more correct to take a thicker piece of iron. A corner 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 wood walls with fire retardant along the entire lightning rod will be a very useful and not a superfluous means of protection against fire.

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

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

obelektrike.ru

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

House and cottage Gardener's calendar June House and buildings Do it yourself

Lightning strikes unprotected private houses and trees, unfortunately, are not uncommon. The presence of lightning protection in the country is necessary - it will discharge the discharge into the ground and help save your property, and sometimes even your 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

The lightning rod can be:

• Rod - a metal pin fixed to the bed (on the roof, near the house, on a tall tree growing near the house). The pin is connected to the grounding system by means of a metal wire. Such a lightning rod looks aesthetically pleasing, but its coverage area is not large. It is easy for them to calculate the area of \u200b\u200bprotection: 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 triangle zone around the perimeter is protected from lightning strikes.

Installation of rod lightning protection

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

Catenary wire 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 dachas, since their design is simple, and installation is not difficult to do with your own hands.

Lightning protection elements

Any type of lightning rod system consists of three mandatory 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 thickness of the coating is 4-7 mm.
• Down conductor is one of the main elements of lightning protection. It is from a copper (d 16 mm²), aluminum (d 25 mm²) or steel (d 50 mm²) wire.
• Grounding is a system of metal rods interconnected by 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 rod. A television mast or a radio antenna can be used, you can also buy an air terminal from one of the leading manufacturers: SCHIRTEC, OBO Bettermann, J Propste, GALMAR;
• Copper, aluminum or steel wire of the recommended cross-section;
• Metal pins, pipes or tapes for grounding;
• Mast (bed);
• Plastic mounts;
• Tools (hammer, drill, shovel).

Installation of catenary wire lightning rod

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

Installation diagram of catenary wire lightning rod

If the roof is covered with flammable materials (wood, plastic tiles), the wire should be 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 air terminal by means of welding, bolts or rivets. The joints are insulated. 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 the cable duct to avoid the negative influence 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. There should be no playgrounds for children and animals walking nearby. Grounding works only in wet ground, which must also be considered when choosing a location.

The order of the 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.

Lightning protection ground loop

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

Fastening the down conductor to ground

Installation of a lightning rod

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

Diagram of a lightning rod in a private house

Installation of the down conductor and grounding of such lightning protection does not differ from that described above. After finishing 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 periodically cleaning the rod post 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 lightning protection device RD 34.21.122-87, then at the right time 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 a specialist to perform such work. Only professionals will be able to suggest which materials are best used specifically in your situation, provide qualified assistance in choosing the right place for installation, and take into account the negative factors from the influence of which the protection may not work.

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

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

Standards

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

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

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

Things to consider when installing

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

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

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

Close location of high-rise objects

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

All of these high-rise buildings are a good target for a lightning discharge and have the so-called "screen effect", in the zone of which a nearby residential building also falls. When calculating the size 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 of the discharge current into the soil.

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

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

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

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

Lightning rod design

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

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

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

Thus, the independent arrangement of a lightning rod for a private house involves the production of the following mandatory elements of protection against thunderstorms:

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

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

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

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

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

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

During installation, they are laid along the walls of the building, and then welded on the one side to the lightning rod, and on the other - to the grounding loop, manufactured 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. In this case, the lightning protection pin itself is securely fixed at the highest point of the structure (on a pipe or on a wooden antenna mast). In the case of using a mesh, it is laid over the entire area of \u200b\u200bthe roof with the formation of cells with dimensions of no more than 12x12 meters (this value is chosen based on the dimensions of the roof and the required quality of lightning protection).

At the points of intersection, the wires are welded and then fixed on the roof of the house with the help of special holders, well insulated from the coating material.

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

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

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

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

The procedure for manufacturing a ground electrode

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

Fulfillment of this requirement is possible only with a minimum electrical resistance of the entire structure of the ground electrode, made from a set of metal blanks. As a rule, it is constructed of 3 thick steel bars or profiles at least 2.5 meters long, driven into the ground not far from the house (at least 5 meters).

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

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

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

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

Lightning protection tips from professionals

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

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 beams to which it is attached, vertical lightning rods up to a meter high are installed. The chimney will be reliably protected by a steel cap, wire "plug" or loop connected to the conductor. The same conductor descends the shortest path along the wall of the house and is connected to the ground. If the length of such a lightning rod is more than ten meters, then it should be grounded on both sides.

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

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

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

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

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

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

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

Grounding should be located at least 5 m away from paths and walkways.

The lightning rod is reinforced on wooden walls and poles with brackets or clamps nailed at a distance of one or two meters from each other. It is useful to lay insulators from a piece of rubber hose under the clamps. Conductors must be laid so that they do not have loops and sharp corners, otherwise they can be broken by forces arising from a lightning discharge. They are closed to a height of about 2.5 m from the ground with a steel pipe, corner or wooden box.

Methods for connecting parts of a lightning rod are shown in Fig. 5. The most reliable - welding or brazing, but you can also use twisting, bandage connection, special clamps or lap joints using bolts and rivets.

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

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

Every three years, they check the health of the connections, clean the contacts, tighten the loose connections or replace them.

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