The third webinar of the "Simply about installing grounding and lightning protection" series
Webinar text. Page 2
Fast navigation by slides:
<< Page 1:
1. Apartment buildings and commercial facilities
2. Lightning protection of apartment buildings and commercial facilities
3. Lightning protection of a hypermarket
4. Calculation of protection reliability
5. Layout of current collectors from the lightning rods
6. Lightning protection grid
7. Lightning protection grid (continued)
8. Metal roof as the lightning rod
Page 2:
9. Layout of the horizontal belts of current collectors
10. Natural building elements as current collectors
11. Grounding in the lightning protection system
12. Grounding in the lightning protection system (continued)
13. Natural grounding devices (base)
14. Foundations in aggressive media
15. Example. Warehouse grounding
16. Example. Lightning protection of an apartment building
Page 3: >>
17. Lightning protection of the roofed gas boiler
18. Examples of calculations for apartment buildings
19. A house of 35 meters high
20. A warehouse of 12.5 meters high
21. What surge protection devices should we use?
22. Recommendations for the LEUTRON surge protection device installation
23. Questions and answers
| Прокладка горизонтальных поясов токоотводов | Layout of the horizontal belts of current collectors |
| В соответствии с требованиями СО 153, если здание имеет высоту более 20 м, каждые 20 метров, а также вблизи поверхности земли прокладываются горизонтальные пояса, которые соединяются с токоотводами. | In accordance with the requirements of SO 153, if the building has the altitude over 20 m, horizontal belts shall be laid in each 20 meters, as well as near to the ground surface, which belts are to be connected to the current collectors. |
| Для соединения токоотводов между собой могут быть использованы зажимы | Clamps can be used for the current collectors connection to each other |
| Заземление и молниезащита на ZANDZ.com | Grounding and lightning protection on ZANDZ.com |
Layout of the horizontal belts of current collectors
— The installation of the horizontal belts of current collectors is only possible, according to the SO 153 requirement, every 20 meters; this also applies to the building height. Near the ground surface, the horizontal belts are installed that are connected to current collectors. To connect the belts with current collector risers, the clamps may be used, which allow creating the X-shaped connections, such as those shown in the picture.
| Естественные элементы здания в качестве токоотводов | Natural building elements as current collectors |
| При установке молниеприемников везде, где это возможно, в качестве токоотводов следует использовать металлические конструкции зданий и сооружений (колонны, фермы, рамы, пожарные лестницы и т.п., а также арматуру железобетонных конструкции) при условии обеспечения непрерывной электрической связи в соединениях конструкций и арматуры с молниеприемниками и заземлителями. | When installing the lightning arresters in any place where possible, one should use metallic structures of the buildings and facilities as the current collectors (columns, girders, framework, fire stairs, etc. as well as reinforcement bars) provided that continuous electrical coupling is ensured in the joints of structures and reinforcement bars with the lightning arresters and ground terminals. |
| Если данное условие не выполняется, прокладываются искусственные токоотводы, либо комбинация естественных и искусственных. | If no such a condition is met, artificial current collectors or a combination of natural and artificial collectors shall be laid. |
| Заземление и молниезащита на ZANDZ.com | Grounding and lightning protection on ZANDZ.com |
Natural building elements as current collectors
— When installing the lightning rods wherever possible, the metal building structures, if any, should be used as current collectors (columns, frameworks, fire ladders, etc.), provided that, of course, this grounding will not be used either for connecting another equipment or will not be used as the ground for welding.
| Заземление в системе молниезащиты | Grounding in the lightning protection system |
| В соответствии с РД 34 при площади здания более 250 м2 в грунте с удельным сопротивлением менее 500 Ом*м, а также площади более 900 м2 в грунте с удельным сопротивлением до 1000 Ом*м вокруг здания на глубине 0,5 м и расстоянии 1 м от стены прокладывается горизонтальный контур. | In accordance with regulatory document RD-34, when the building area is over 250 m2, in the soil with the resistivity not less than 500 Ohm, as well as when the area is over 900 m2, in the soil with resistivity up to 1,000 Ohm*m, the horizontal circuit is installed around the building at the depth of 0.5 meter and the distance of 1 m from the wall. |
| Пункт 1.7 РД 34 определяет, что заземлитель молниезащиты и заземлитель электроустановок (защитное заземление) выполняются общими | Item 1.7 of RD 34 determines, that the lightning protection ground terminal and the electrical installations ground terminal (protective grounding) shall be common |
| Об этом же говорят пункт 3.2.3.1 СО 153 и пункт 1.7.55 ПУЭ 7 изд. | The same is provided for in item 3.2.3.1 SO 153 and item 1.7.55 EIC Rev. 7. |
| Заземление и молниезащита на ZANDZ.com | Grounding and lightning protection on ZANDZ.com |
Grounding in the lightning protection system
– In accordance with regulatory document RD-34, when the building area is over 250 m2, in the soil with the resistivity not less than 500 Ohm, as well as when the area is over 900 m2, in the soil with resistivity up to 1,000 Ohm, the horizontal circuit must be installed around the building at the depth of 0.5 meter. Item 1.7 specifies that the grounding device of the lightning protection and the grounding device of electrical installations or the protective grounding are made integral, i.e. they are connected by a single circuit. Item 3.2.3.1 and other items shown in the slide specify the same.
.jpg)
| Заземление в системе молниезащиты | Grounding in the lightning protection system |
| Если здание имеет меньшую площадь, то в месте спуска каждого токоотвода устанавливается вертикальный электрод длиной 3 м. | If the building has smaller area, then a vertical electrode with the length of 3 m shall be installed at the point of each current collector riser connection. |
| Либо, если грунт не позволяет его смонтировать, устанавливается горизонтальный лучевой электрод длиной 3 м | Alternatively, if the soil prevents from installation thereof, a horizontal wire-beam electrode with the length of 3 m shall be installed. |
| Заземление и молниезащита на ZANDZ.com | Grounding and lightning protection on ZANDZ.com |
Grounding in the lightning protection system (continued)
– In accordance with the governing document, if the building has the areas less than 250 m2 and 900 m2, then in the respective cases, at the location of each current collector riser, the vertical electrode with the depth of 3 meters is installed.
.jpg)
| Естественные заземлители (фундамент) | Natural grounding devices (foundation) |
| В качестве заземлителей защиты от прямых ударов молнии во всех возможных случаях (пункт 1 8 РД 34) следует использовать железобетонные фундаменты зданий и сооружений. | Reinforced concrete foundations of the buildings and facilities shall be used as ground terminals for protection against direct lightning strike in all cases where possible (item 1.8 of RD 34). |
| Необходимым условием является непрерывность электрической связи по их арматуре и присоединения ее к закладным деталям. | The pre-condition is continuity of electrical coupling through the reinforcement bars and connection to the embedded parts. |
| Следует учесть последствия протекания тока молнии по преднапряженному бетону | One should consider the consequences of the lightning current flow by the pre-stressed concrete. |
| При невозможности использования фундаментов предусматриваются искусственные заземлители | Artificial ground terminals are provided for in case of impossibility to use the foundations |
| Заземление и молниезащита на ZANDZ.com | Grounding and lightning protection on ZANDZ.com |
Natural grounding devices (foundation)
— Now, let us talk about the natural grounding devices. In general, the foundation may be used as the natural grounding device to protect against the direct lightning strikes. It is provided in item 1.8 of RD-34 for all possible cases. Hence, it is permitted to use the reinforced concrete foundations of buildings and structures.
| Фундамент в агрессивных средах | Foundations in aggressive media |
| 1. Использование битумных, эпоксидных и оклеенных покрытий, которые усилены рулонами с защитной стенкой может значительно увеличить сопротивление заземления! | 1. Use of bituminous, epoxy and glued coatings reinforced by rolls with a protective shield could increase the grounding resistance significantly! |
| 2. Битумная и битумно-латексная гидроизоляция обычно не оказывает существенного влияния на сопротивление заземления. | 2. Usually, bitumen and bitumen and latex hydro-isolations do not have a significant impact on the grounding resistance. |
| 3. Естественное заземляющее устройство можно дополнить искусственными заземлителями для соответствия норме. | 3. The natural grounding device may be supplemented by the artificial grounding devices in order to meet the standard. |
| Чем агрессивнее среда, тем выше сопротивление заземляющего устройства из-за принятых защитных мер в соответствии со СНиП II-28-73! | More aggressive the medium, higher the ground terminal resistance due to applied protective measures according to SNiP II-28-73! |
| Заземление и молниезащита на ZANDZ.com | Grounding and lightning protection on ZANDZ.com |
Foundations in aggressive media
– The foundations in aggressive media. The use of bitumen, epoxy, and glued coverings enhanced by the rolls with protective walls may generally increase the grounding resistance. Usually, bitumen and bitumen and latex hydro-isolations do not have a significant impact on resistance. The natural grounding device may be supplemented by the artificial grounding devices in order to meet the standard. The more aggressive the media, the higher the resistance of the grounding device due to the protection measures.
| Пример. Заземление склада | Example. Warehouse grounding |
| Вокруг здания прокладывается горизонтальный контур длиной 160 м. | Horizontal circuit with the length of 160 m shall be laid around the building. |
| Расчет выполняется в программном обеспечении ОАО "ЭНИН" которое позволяет оценить реальный коэффициент использования заземлителей. | The calculation is performed in OAO ENIN software that allows evaluation of real utilization factor of the ground terminals. |
| При удельном сопротивлении грунта 100 Ом*м Расчетное удельное сопротивление: 1,63 Ом | At the soil resistivity of 100 Ohm*m Calculated soil resistivity: 1.63 Ohm |
| С учетом непрерывной электрической связи колонн з арматурой фундаментов и присоединением к горизонтальному контуру | By taking into account continuous electrical coupling of the columns with the foundation reinforcement and connection to the horizontal circuit. |
| Расчетное удельное сопротивление: 1,1 Ом | Calculated resistivity: 1.1 Ohm |
| Заземление и молниезащита на ZANDZ.com | Grounding and lightning protection on ZANDZ.com |
Example. Warehouse grounding
– Now, we will consider the example of warehouse grounding. As we can see, a horizontal circuit of 160 meters is installed around the building. It is a full circuit that follows the building perimeter. This design was performed using the special software provided by ENIN. It allows evaluating the actual utilization ratio of any configuration of horizontal and vertical grounding devices as well as their relationship and mutual influence. At the soil resistivity of 100 Ohm*m, the design resistivity in this design will be 1.63 Ohm.
| Пример. Молниезащита многоквартирного дома | Example. Lightning protection of an apartment building |
| Мероприятия по молниезащите и заземлению выполняются такими же, как и для гипермаркета. | The lightning protection and grounding activities shall be the same as for a hypermarket. |
| Дом имеет высоту 30 м, поэтому прокладывается 2 горизонтальных пояса на высотах 2 и 22 м. | The building has the height of 30 m, so 2 horizontal belts shall be laid at the heights of 2 and 22 m. |
| Заземление и молниезащита на ZANDZ.com | Grounding and lightning protection on ZANDZ.com |
Example. Lightning protection of an apartment building
– The lightning protection of an apartment building is usually the same as for a hypermarket. In this case, we can see that the house is 30 meters high; therefore, two horizontal belts are installed at the heights of 22 meters and 2 meters.
<< Previous page
slides from 1 to 8
Next page >>
slides from 17 to 22 + questions
Useful materials for designers:
- Webinars with participation of lead experts of the industry
- All for calculation of the earthing and lightning protection
- Useful materials: articles, recommendations, examples
Related Articles:
