A summer pavilion is a light architectural structure usually located in the garden or park, with benches and a table intended to protect against rain and direct sunlight and serving for rest and conversation. Usually, no lightning protection and grounding are provided for these facilities, but the customer requested it. The ZANDZ Technical Center has received a request to calculate the lightning protection for a summer pavilion in the Moscow Region. Let us continue with more detailed review of our offered solution.
Calculation of the lightning protection for a summer pavilion in the Moscow Region
Facility: a summer pavilion in the Moscow Region
Кирпичная кладка - Brickwork
Конструкция камина - Fireplace structure
Минеральная вата - Rockwool
Figure 1. Facility plan.
Task: to calculate lightning protection system for a summer pavilion located in the Moscow Region
Solutions to meet the requirements to the lightning protection system of the summer pavilion in the Moscow Region:
- The lightning protection is made in accordance with the Electrical Installations Code (EIC), Rev. 7, SO 153-34.21.122-2003 Guidelines for Lightning Protection of Buildings, Structures, and Industrial Utilities (hereinafter referred to as SO) and RD 34.21.122-87 Guidelines for Lightning Protection of Buildings and Structures (hereinafter referred to as RD).
- According to RD, the facility is considered as the 3rd category lightning protection facility. The system reliability shall be at least 0.9.
- The lightning protection of the facility is implemented using 2 x 2 m lightning arresters installed on holder to walls (GL-21101G). 1 m for securing and 1 m upwards.
- A copper-plated steel wire (copper coating thickness of at least 70 μm), d8 mm (GL 11149), is used as a current collector.
- Down collectors are installed using holder GL-11747M on roof slopes, GL-11703M on vertical surfaces. The accepted pitch of terminals is 0.8-1.0 m.
- The universal GL-11551M clamp is used to connect rolled products over the length and in assemblies.
- All metal elements located on the roof must be connected to the main conductor cable with the terminals GL-11545M. Stairs, railings, are attached using the terminal-clamp GL-11514N.
- The vertical copper-plated steel electrodes with the length of 3 m are used as the grounding devices at the downdrops of the down conductors. The copper-plated steel strip with a cross-section of 30x4 mm, combining all vertical electrodes is used as a horizontal ground electrode. The distance to the facility foundation is at least 1 m. Strip deepening is 0.5 to 0.7 m.
- According to EIC-7 issue, par.1.7.55, Grounding devices for protective grounding of electrical installations for buildings and structures and the 2nd and 3rd categories lightning protection of these buildings and structures, as a rule, shall be common.
- If there are concrete-steel constructions, they shall be connected to down conductors/grounding device.
- Connection to the grounding device is carried out using ZZ-005-064 clamps.
The results of calculation performed using the software developed by the Krzhizhanovsky Energy Institute (OAO ENIN):
density of lightning strikes into the ground is 4 strikes/sq. km per year.
Total number of strikes into the system is 0.012 (once every 83 years).
The total number of breakouts into the system is 0.0013 (once every 769 years).
The probability of a blowout into the system's facilities is 0.1.
System reliability is 0,9.
Figure 2 shows hardware layout.
Table 1 includes the list of required hardware and materials.
Условные обозначения: - Legend:
- Молниеприемник-мачта высотой 2 м на держателях - 2 m lightning arrester on holders
- проволока стальная омедненная диаметром 8 мм - Steel copper-plated wire dia. 8 mm
- универсальный зажим-соединитель для проволоки - Multipurpose connecting clamp for wire
- фальцевая клемма для крепления к металлическим конструкциям - Grooving terminal for attaching to metal structures
- зажим-хомут - Clamp
- полоса стальная омедненная сечением 30х4 мм - Steel copper-plated bar 30 x 4 mm
- зажим для подключения проводника - Clamp for wire connecting
- опуск токоотвода - Downdrop
- вертикальный заземлитель длиной 3 м - 3 m vertical grounding arrangement
Figure 2. Hardware layout for the lightning protection of the summer pavilion in the Moscow Region
Table 1. List of material requirements.
Do you have any questions about lightning protection of the summer pavilion or other facilities? Please, contact the ZANDZ Technical Center!
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