The Passage is a gallery passway with rows of shops between two parallel streets. Such a design requires a good cross and the constant presence of a large number of people. The Passage in question is located in the Southern Federal District with a high density of lightning strikes, because of this crowds of poeple are at increased risk due to strikesof lightning.
The use of rod interception rods will be the most reliable way of lightning protection of the Passage. They intercept a direct lightning strike and safely divert it to the grounding arrangement.
Get to know the lightning protection solution of the Passage from the news.
Task
Calculate the lightning protection of the Passage.
Solution
Passage lightning protection calculations were made in accordance with the following documents:
- "Electrical Installations Code" (further – EIC), EIC 7th edition
- "Instructions for the installation of lightning protection of buildings, structures, and industrial communications" SO 153-34.21.122-2003 (further – SO).
- "Instructions for mounting the lightning protection of buildings and structures" Working Documentation 34.21.122-87 (further – WD).
Interception rods are used to protect the Passage from lightning strokes. Lightning discharger consists of an interception rod, intercepting a lightning discharge, the main conductor cable, and the ground electrode. All these elements let us to divert lightning current into the ground safely, without any damage to the protected facility. The Passage refers to ordinary objects from the point of view of lightning protection in accordance with the SO and to the 3rd category according to WD.
Description of the lightning protection system of Passage
A set of arrangements ensuring compliance with the lightning protection requirements is based on the following solutions:
- Mounting of 2 interception rods with a height of 10 m, is carried out with fastening to the wall. It is taken into account that 2 m of the height of interception rods are necessary for mounting.
- Interception rods are interconnected to organize two main conductor cables using galvanized steel wire D = 8 mm from each interception rod. The main conductor cables are mounted (with mounting step 0.6-1 m):
- on the slopes of the roof it is carried out using terminals GL-11747A;
- to the walls with connection terminals GL-11703A.
- Connection and branching of main conductors are made using terminals GL-11551А.
A set of measures to ensure the necessary requirements for the grounding arrangement is represented by the following solutions:
- Mounting of a grounding arrangement consisting of a horizontal electrode (galvanized strip with a cross section of 4x30 mm), a depth of 0.5 meters, a distance of 1 m from the wall and vertical electrodes (pins made of galvanized steel with a diameter of 16 mm) 3 m long.
- The connection of the vertical and horizontal electrodes between each other is carried out by using terminal ZZ-005-064.
- The connection of the main conductor cable with the output of the galvanized ground strip is performed with the control tetminal GL-11562A.
- The design of the grounding arrangement corresponds to clause 1.7.55 of EIC Grounding arrangements for protective grounding and grounding for lightning discharges are common.
The location of the elements of lightning protection system and the grounding arrangement is shown in Figure 1. The depicted protection area corresponds to area B, constructed as per Appendix 3 of WD.
Picture 1. Passage lightning protection layout
Условные обозначения - Conventional symbols
Стержневой молниеприемник H=10 м - Interception rods l H = 10 m
Горизонтальный заземлитель - Horizontal ground electrode
Вертикальный заземлитель длиной 3 м - Horizontal ground electrode 3 m long
Токоотвод - Main conductor cable
Зажим для подключения проводника (ZZ-005-064) - Main conductor connection terminal (ZZ-005-064)
Зажим контрольный (проволока+полоса) (GL-11562A) - Control terminals (wire + strip) (GL-11562A)
Accessories for the Passage lightning protection
Do you have questions about grounding and lightning protection of the Passage? Please, contact the ZANDZ Technical Center!
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