Lightning protection is a set of measures aimed at reducing the risk of damage or destruction of buildings and premises, transport infrastructure facilities, communications, technological equipment from the effects of atmospheric electricity. In the article we will tell you how the Ministry of Health works, and how to apply for a passport for it.
From this article you will learn:
What is and why lightning protection and grounding are needed
Atmospheric electricity is dangerous because of its unpredictability. Up to 16 million thunderstorms occur annually on the globe, that is, about 44 thousand per day. As a result of a direct lightning strike, destruction of buildings, fires, death of people located at these facilities or in dangerous proximity can occur. It can also result in equipment failure or damage.
The lightning discharge at the breakdown site is approximately 30 kV per 1 cm. Lightning always hits the place where it is easier for charged electrons to propagate. Therefore, the metal tip of the lightning rod will accumulate lightning discharges, for which this is the easiest way.
The most lightning hazardous period of the year in Russian Federation is the summer season, mostly in July. As a rule, in July, thunderstorms are most frequent, as the height of the clouds increases to 12-14 km above the ground, and because of this, the charge between them increases.
Types of lightning protection
Lightning protection devices (LP) are a way to protect infrastructure facilities that are designed to neutralize a lightning discharge.
The lightning discharges that we see in the window are already the reverse course of lightning. The structure of the MS resembles a ring. A direct strike is a direct contact of a lightning channel with a building or structure, accompanied by the flow of current through it.
There is also a secondary lesion associated with pointing potentials at metal elements structures, equipment, in non-closed metal circuits, caused by nearby lightning discharges and creating a spark hazard inside the protected object.
High potential drift - transfer to the protected building or structure through extended metal communications (underground, surface and aboveground pipelines, cables, etc.) of electrical potentials arising from direct and close lightning strikes and creating the danger of sparking inside the protected object.
Lightning protection device
MOH is divided into external and internal. External is an elementary type of protection against electric discharge during a thunderstorm and is designed to intercept lightning and safely lead it to the ground. Thus, at the moment of a direct strike into the object, the lightning protection system must take on the full strength of the lightning discharge current and divert it through the down conductors to the ground circuit, where the energy will safely spread in the ground.
Lightning protection project
An important task in the design of an object is the reasonable choice of the OH system. This is an important part of the construction project in terms of environment, preservation of buildings and structures, life support facilities and industrial communications from the effects of atmospheric electricity.
It should be noted that in Russia there are standards for the categorization of protected objects and the effectiveness of lightning protection measures.
When designing, methodological guidelines are used, which are given in:
- RD 34.21.122-87,
- SO 153 - 34.21.122 - 2003,
- GOST R IEC 62305-1-2010,
Equipment
External MZ consists of:
- lightning rod,
- lightning rod (down conductor),
- horizontal ground loop,
- deep rod grounding.
Installation of lightning protection
The following requirements are imposed on the installation of the ground loop of the PUE:
- Accessible location of ground electrodes for visual inspection once every six months during the period of the greatest and least freezing of the soil (hot and cold seasons), as well as for opening the soil at least once every 12 years.
- The strength of the connecting elements - a deep earth rod must be securely attached by bolting or welding to a horizontal ground loop. The grounding conductor should not crawl out of the ground, since in this case the lightning discharge current will not spread inside the soil, a reverse transformation will occur, the consequences of which will be catastrophic for the MP object.
- The level of reliability of devices that act as fuses.
- Measurement of grounding elements. The measurement must be carried out by accredited electrical laboratories. Insulation resistance protocol is always .
To prepare for installation, it is necessary to determine the dimensions of the building and the materials used in the structures, determine the places for installing grounding, lowering down conductors from lightning rods to the ground loop, as well as installing lightning rods. Then the required number of down conductors, lightning rods, ground electrodes, auxiliary elements - holders and fasteners is calculated.
Installation includes a sequence of operations:
- installation of holders;
- installation of lightning rods and laying of conductors;
- grounding mounting (laying a contour of metal strips or rods into a trench around the building).
Attention
After installation in without fail ground resistance should be checked, which should not exceed 15 ohms. Then the ground loop will be connected to the common ground loop of electrical installations in the building.
Active lightning protection
In addition to traditional external systems, active MZ is now widespread - an installation with a system of preemptive streamer emission.
The principle of operation is based on the prevention of a lightning strike by forming its own artificial streamer, which is directed towards the lightning leader. This effect can be achieved, for example, by installing a parallel chain of capacitors and arresters.
If the lightning leader approaches such a lightning rod, there will be an increase in the electric field strength and a breakdown of the arresters, a spark discharge occurs. The air around is ionized, which contributes to the appearance of ascending streamers, moreover, ahead of the approach of the descending leader. Such an advance interval is the main characteristic of the installation and is indicated in its passport.
This is how an active system works in general terms. Manufacturers claim that the protective zone of such devices significantly exceeds the traditional external MOH system (Franklin rod). However, there is currently no reliable evidence that this system is more effective than the traditional one.
Internal lightning protection system
In addition to the external one, which is, in fact, an elementary Franklin rod, there is also an internal MM, which is a complex protective devices from surge voltages - resistors and inductors. In no way does it replace the external one. The purpose of an SPD is to protect expensive network equipment. SPDs are divided into three types.
It is known that there are direct and indirect lightning strikes. Direct - a lightning strike into a building or into the poles of communication or power transmission lines connected to it. Indirect - occurs due to lightning strikes near communication lines.
Type 1 surge voltage from direct impact. It is usually installed in rural areas with overhead power lines or communications, in buildings with lightning rods or located near high-rise objects (towers mobile communications, tall trees, etc.).
Type 2 surge voltage from indirect impact. In this case, the stored energy is about 17 times less than the energy of a direct impact.
Type 3 for its survivability requires the use of types 1 and 2 in front of itself and is installed directly next to the consumer. It can be, for example, a regular surge protector such as UPS or a voltage stabilizer.
Passport of lightning protection - sample
The passport is transferred to the owner of the object of protection after the installation of the lightning protection device. It contains a title page, inspection and verification protocols, as well as a diagram with the designation of measurement control points.
Find the sample document on labor protection you need in the Reference system "Labor protection". Our experts have already prepared 2506 templates!
A sample passport for a grounding device is available in the Guidelines for monitoring the state of the memory (RD 153-34.0-20.525-00).
This document should contain information about the measurements taken. The passport of the grounding device is kept by the person responsible for the operation of the building or by the chief power engineer.
A visual inspection of the grounding device is carried out by the commission of the organization, and the measurement of the ground loop is carried out.
To ensure the long-term safety of the circuit, it is necessary to regularly inspect it, as well as timely repair of bolted or welded joints in accordance with clause 1.2 of the Regulation on preventive maintenance industrial buildings and structures, approved by the Decree of the USSR Gosstroy of December 29, 1973 No. 279 MDS 13-14.2000.
The lightning protection passport is a document that is drawn up by the parties after the installation of the object’s lightning protection system in order to confirm its compliance with safety standards and subsequent protection of the customer in case of claims (disputes) from the supervisory authorities fire safety. The installation company provides guarantees, which indicate the parameters of the object, as well as its specifics. Work is underway to strengthen and ground positions. All this is formalized, after which it is transferred directly to the customer. All data and indicators that were at the time of the verification are entered into the protocol. It is evidence that the operation of the facility is absolutely safe.
Guarantees provided by the lightning protection passport
Passport for lightning protection is issued during the acceptance of work. Before that, experts inspect not only the object itself, but also the surrounding area. Only representatives of the relevant authorities or specialized companies can perform such work.
Certification is carried out during test work during the commissioning of the building (structure). It repeats after a certain time period. The exact dates must be indicated in the issued document. It will guarantee that everything is in order with the house (or any other object), and in the event of a lightning strike, the building will be reliably protected.
Drawing up an act involves mutual responsibility, because a deliberate violation of its conditions can lead to problems.
An annex is also added to the passport document, in which there will be detailed instructions in case of unforeseen situations. Lightning protection is provided by the following devices:
- down conductor;
- lightning rod;
- grounding element.
The principle of operation is as follows: the lightning rod intercepts. Then the down conductor contributes to the removal of the lightning charge, after which the ground electrode connects it directly to the ground. The charge fades and is no longer dangerous. All parts of the system must be properly connected to each other.
Advantages of the grounding passport
The lightning protection passport of a building has a number of advantages:
- guarantees the safety of the client;
- insures against potential threats (lightning);
- makes the structure resistant to external influences.
Now it is required by many representatives of public services (fire, gas inspections). The document is filled in several copies at once. This is necessary so that all parties can control the process. A sample filling can be found on our official website. You can also view all of the items on the form.
If you do not draw up such documents, then there is a high probability that you may suffer during a thunderstorm.
Lightning protection is issued not only for residential, but also for industrial facilities. This rule is established in accordance with GOST. Right choice category, as well as competent installation of all systems will provide reliable protection even during serious disasters. High-quality electrical installation will prevent all sorts of problems. Every year, thousands of people around the world become victims of the elements, where ball lightning also poses an increasing danger.
A person must himself understand that in the absence of the necessary lightning protection devices, he puts himself at great risk. Many buildings do not meet modern safety requirements for a long time, so we actually live on a powder keg. If you do not check for a long time, then the risk of lightning strikes increases. The mains neutral can also fail. Her inspection is carried out exclusively by professionals.
The passport contains a certificate that the company can carry out such work, as well as a document that the devices meet all modern requirements. An example of filling it out can be viewed on our website, where you can also apply for lightning protection, which will make your life safer.
Registration of a lightning protection passport
The company's specialists will conduct a ground loop and issue a passport. Experienced employees have been doing this type of work for a long time. Their main tasks include:
- implementation of all required measurements;
- production of a lightning rod project, which will be agreed with the customer;
- installation of a structure that brings the proper result;
- coordination of the installation with the relevant authorities.
The measurements contained in the passport will record the current state of affairs. So, for example, protection can also be carried out with the help of specific devices, for example, a mast. This option is more suitable for rural areas. All ports will be securely connected to each other, which will make the design resistant to even the most serious threats.
A sample of filling out a lightning protection passport, its form and the text of the application can be downloaded on our website. The standard format is mainly used, but it can be supplemented with some specific items.
Alef-M employs only experienced employees who use the most modern equipment, which is a guarantee of high-quality and durable results. The lightning protection passport includes:
- device layout plan;
- date of installation;
- information about the specifics of grounding conductors;
- corrosion index;
- report on the work carried out and tests;
- resistance value;
- grounding device diagrams.
The specialist enters data on the work performed, and what faults were eliminated (if any). More detailed information can be found in the material "Documentation of lightning protection". The site has a PDF file, which shows the prices of all goods and services.
The implementation of the work will improve the safety of the power facility.
Contact the professionals, in "Alef-Em" - an individual approach to each client. Thanks to this, it is always possible to get exactly what you need.
To call an experienced master, just call the indicated phones. All your questions will be answered. We use devices with a foreign passport, as well as the best domestic products.
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Lightning protection, regardless of whether it is an industrial facility, a public building or a private cottage, is necessary - primarily because it will prevent the death of people and fire, which can occur with a direct lightning strike.
Options for creating lightning protection
For each version of roofing, there are certain types of lightning protection. For example, the creation of protection against the consequences of a lightning strike for a soft roof is performed using a special mesh or special holders. As seen in the photo, lightning protection nets consist of metal conductors, which are laid along the roof ridge, and current-conducting drops, grounded separately. Their fixation is carried out using the material used for the installation of the roof. There is another way of arranging lightning rods, which is considered universal, this is the installation of masts on two gables of the building, between which a cable-wire is attached.
The design of lightning protection is different, and it is chosen based on the specific situation. So for a galvanized roof, the following method is used: a steel wire with a diameter of 6 millimeters is rolled around the perimeter into the roofing iron and grounded at the corners of the roof. In this case, the lightning protection of the chimney, which rises above the ridge, is created by mounting the lightning rod on the chimney, it is also grounded. A roof protected in this way will not be affected by a thunderstorm.
It has a number of features lightning protection of a warehouse and an industrial building when the roof is made of metal tiles. The point is that this roofing material durable and easy to install, but not always safe in operation, since the design of its sheets has a number of features.
Metal tiles are made of corrugated aluminum or steel plates, and they are covered with plastic on top on both sides (they are similar in functionality to capacitor plates). Roof sheets isolated from each other and from the ground are capable of accumulating electrical potential in the event of a lightning discharge - we should not forget that in some cases an electrostatic discharge reaches tens of thousands of volts.
It is known that there are regions on the territory of the country where thunderstorms occur more often than in other areas - before choosing a metal tile as a roofing material, it is necessary to take into account the above risks. Such objects belong to the 1st and 2nd class in terms of lightning protection, and the creation of lightning rods on them must be done correctly. At the same time, a lightning protection passport is entered for each grounding device in operation.
Lightning protection systems: active and passive
To make a decision on the admission to the operation of public and industrial buildings and structures, a lightning protection protocol is required, only certified laboratories can draw it up (read: "").
The passive system has been used for several centuries.
Lightning protection of a dacha, a residential building, a production facility may have one of such lightning rods as:
- cable;
- rod pin;
- special mesh.
Relatively recently, an active one appeared and very quickly became popular. Its design is a mast mounted on the roof with a lightning rod attached to it. An active system differs from a passive one in quick installation and a wider protection zone. Compared to a rod lightning rod, it covers an area 5 times larger. An active system is relevant when lightning protection of churches, bell towers, water towers, television centers, etc. is required.
Lightning protection of a soft roof
Information on how to create an active or passive lightning protection of a cottage with your own hands on a soft roof can be found on the Internet. If a passive system is mounted, then it is used from 6 mm steel wire with a step from 6x6 meters to 12x12 meters. It is placed under a layer of insulation (necessarily fireproof or slow-burning).
We install grounding in a private house, a fairly detailed video instruction:
It is desirable that the installation of the grid is carried out in the process of roofing. If soft roof installed, then problems are possible. The biggest one is that there is a possibility of surface damage during the installation of the lightning protection mesh. This is due to the fact that such materials for lightning protection as steel wire are supplied in coils and they have to be straightened directly on the roof. Also, when carrying out work, it is necessary to move along the roof, and the integrity of the coating is not always possible to maintain (read also: "
Sample passports of lightning protection device and grounding device
(GUP MO "MOSOBLGAZ")
Branch of State Unitary Enterprise MO "MOSOBLGAZ" "Odintsovomezhraygaz"
THE PASSPORT
grounding device(name of building, structure)
Project completed
Date of installation of the grounding device (GD)
Year of commissioning
I.
executive scheme grounding device
II. Maintechnical details
Ground electrode type (material, profile, section):
- horizontal
The size of the vertical ground electrode (diameter, cross-sectional area):
Number of vertical ground electrodes (pcs.):
Depth of vertical grounding (m):
Distance between vertical ground electrodes (m)
Connecting horizontal stripes: width mm, thickness mm.
Depth of horizontal strips of the contour (m):
Used natural grounding conductors
(inner loop)
Material shape and dimensions
Used building elements
Grounding device resistance (design), Ohm
Soil characteristic, soil resistivity (Ohmm)
III. Information about the repairs and changes made,
introduced into the grounding device
IV. Status Check Results Datagrounding devices
Inspections of grounding devices
* Visual inspection of the visible grounding device)
Inspection with selective opening of the soil.
Measuring the resistance of a grounding device (resistance to current flow)
| date | № protocol | date next checks | Test results | Note |
Checking the presence of a circuit between the grounding device and grounded elements, incl. with natural earthing conductors (resistance of transitional contacts)
The passport was:
Passport checked:
Chief power engineer of the branch
SUE MO "MOSOBLGAZ"
"Odintsovomezhraygaz"
Position, signature, surname and initials, date
Checking the status of entries in the passport
| date | Position inspector | Remarks | Signature |
Note: Protocols are attached to the passport:
Grounding device resistance measurements.
Checks for the presence of a circuit between the ground loop and grounded elements.
Defective statement
State unitary enterprise
gas facilities of the Moscow region
(GUP MO "MOSOBLGAZ")
Branch of State Unitary Enterprise MO "MOSOBLGAZ" "Odintsovomezhraygaz
1. PURPOSE
1.1. Lightning protection is designed to protect the equipment placed on the mast from lightning strikes by receiving and diverting discharges to the ground.
2. DESCRIPTION OF THE DESIGN
2.1. Lightning protection consists of 2 parts: lightning receiving part, grounding part.
The lightning-receiving part is a receiver and down conductor.
2.2 The lightning rod is a steel rod up to 2 m long, which is mounted on the mast using insulating (non-conductive) brackets. The lightning rod is connected to the down conductor using special clamps (or threaded connections) treated with a conductive paste to improve the quality of the connection.
2.3. The down conductor is an insulated rod conductor ( insulated wire), which is connected to the grounding part (grounding system).
Fig.1. Lightning protection of a mast with equipment
3. COMPLETENESS
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3.1. receiving part Name |
Quantity, pcs. |
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Lightning rod L=2m |
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Insulating bracket with fixings included |
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Current lead insulated with copper rod d=8-10mm (length is selected depending on the height of the mast) |
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Screed for down conductor |
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Ground Stretch Insulator |
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Universal clamp made of galvanized steel (electrode/strip/rod) |
Lightning protection can be supplied both with a grounding system and without it.
4. INSTALLATION PROCEDURE
4.1. Assemble and fix the lightning rod on the mast, according to the diagram in Fig.2.
4.2. Connect the lightning rod (1) to the down conductor (3) using a clamp (6) using conductive paste.
4.3. Connect the stretching of the upper level of the mast, located on the side of the lightning rod, to the mast through the insulator (5) (into the break of the cable brace, as a conductor).
4.4. Fasten the down conductor (6) to the extension using cable ties (4).
4.5. Install and secure the mast.
4.6. Connect the down conductor (3) to the earthing system.
5. CARE
Lubricate all threaded connections with grease at least once a year.
6.STORAGE PACKAGING TRANSPORT
Lightning protection should be stored in the manufacturer's container.
Storage in a packed state is allowed in equipped warehouses with a relative air humidity of not more than 75% and the absence of acid and alkali vapors.
Packed lightning protection can be transported by any type of transport.
7. MANUFACTURER WARRANTY
The warranty period for lightning protection is one year from the date of installation (commissioning), but not more than 18 months from the date of manufacture.
8. ACCEPTANCE CERTIFICATE
Lightning protection complies with the requirements of design documentation and is recognized as fit for operation.
