Shopping center lightning protection project


Object: shopping center (SC). 
It is necessary to make lightning protection system. The right axis of the building is made of glass. All metal elements protruding over the roof of the building must be connected to down conductors.
Soil: clay loam.
Soil resisitivity: 100 Ohm*mPreferable grounding variant: artificial grounding device with the resistance nor mote than 10 Ohm.



The calculations were performed in accordance with the EIC 7th ed., IS 153-34.21.122-2003 "Instructions for lightning protection of buildings, structures, and industrial communications" (hereinafter IS) and AD 34.21.122-87 "Instruction for lightning protection of buildings and structures" (hereinafter AD).

Shopping centers refer to ordinary constructions in terms of lightning protection in accordance with the IS and to category 3 according to the AD. The required reliability of lightning protection system - 0.9.

According to EIC-7, p. 1.7.103. The total speading resistance of the ground electrodes (including natural) of all repeated groundings of the PEN conductor of each overhead line at any time of the year should not exceed 10 ohms at line voltage of 380 V of the three-phase power supply or 220 V of a single-phase power source.

Lightning protectio is implemented in the form of the rod system - five air terminals masts 6 meters high, and organization of lightning protection mesh on the glass part of the building roof. The size of the cell of the lightning protection mesh is not more than 10x10m. Type of mesh - copper-bonded steel with the diameter of 8 mm, thickness of the coating 70 micron (GL-11149). 

Fixation of mesh is carried out by means of self-stick a clamps GL-11706, on flat surfaces down conductors are fixed with the help of the clamp GL-11711 ,on vertical - with GL-11703A.

The distance between the clamps - 0,8- 1,0 m. To connect the mesh over the length and in the mesh nodes, a universal clamp GL-11551A is used.

Air terminal masts are mounted on horizontal surfaces on three concrete bases (included into the kit). 

Copper-bonded wire 8 mm in diameter is used as down conductors (GL-11149).

The distance between the mesh and the down conductors- not more than 25 m.
The grounding device is designed as a contour around the perimeter of the building. Horizontal conductor - copper-bonded steel tape 30x 4 mm (GL-11075). 8 copper bonded steel electrodes D=14 mm, L=3 m are used as vertical electrodes. Verical electrodes are installed in places of downdrop of down conductors. Distance from the building base not less than 1 m.

The results of the calculation performed by the software, developed by JSC "Energy Institute to the name of G. M. Krzizhanovsky" (JSC "ENIN"):

Taking the density of lightning strikes into the ground - 6.0 strikes / sq km per year;

the total number of breakthroughs (direct strikes into the objects bypassing lightning rods) - 0,016 (once in 58 years).
Protection reliability- 0,928.


Calculation of grounding device resistance:

Resistance of a vertical electrode:

Resistance of a vertical electrode

where ρeq - equivalent soil resistivity, ohm · m; L - length of the vertical electrode, m; d - vertical electrode diameter, m; T- deepening - distance from the ground surface to the ground electrode, m;

Resistance of a horizontal electrode:

Resistance of a horizontal electrode

ρ - soil resistivity, Ohm* m;  b - horizontal electrode tape width ,m; Lгор - horizontal electrode length, m.


where t - deepening of the electrode top, m

Impedance of the grounding device:

Impedance of the grounding device

where n - number of kits; Kисп - utilization ratio;




The design resistance of the grounding device is 1.68 ohms, which is less than the permissible resistance of 10 ohms.

The list of required materials:

Fig Product item Product Q-ty Weight, kg
1 GL-21125 GL-21125 GALMAR Air terminal mast (6.0 m on 3 concrete foundations; two-stage catenary wire support; galvanized steel) 5 117
2 GL-11149-10/20/50 GL-11149-10/20/50 GALMAR Copper-bonded wire (D 8mm / S 50 mm²; coil -10/20/50 meters) 450
(in meters)
3 GL-11711 GL-11711 Clamp on a flat roof for the down conductor (plastic, concrete) 160 1
4 GL-11706 GL-11706 GALMAR Holder on a flat roof for down conductor (D8 mm; for bonding, plastic) 170 0,01
5 GL-11551A GL-11551A Clamp for the connection of down conductors (painted galvanized steel) 40 0,09
6 GL-11703A GL-11703A Clamp to the facade for the down conductor with its elevation above the clamp to 15 mm (Painted galvanized steel) 120 0,02
7 GL-11562A GL-11562A GALMAR Control clamp for connecting down conductors, wire + tape (painted galvanized steel) 10 0,13
8 ZZ-001-065 ZZ-001-065 ZANDZ Copper-bonded threaded grounding rod (D14; 1,5 m) 16 1,9
9 ZZ-002-061 ZZ-002-061 ZANDZ Threaded coupler 9 0,082
10 ZZ-003-061 ZZ-003-061 ZANDZ Starting tip 8 0,074
11 ZZ-004-060 ZZ-004-060 ZANDZ Driving head for a breaker hammer 4 0,088
12 ZZ-005-064 ZZ-005-064 ZANDZ Clamp for connecting conductor (up to 40 mm) 12 0,312
13 ZZ-006-000 ZZ-006-000 ZANDZ Conductive grease 2 0,152
14 ZZ-007-030 ZZ-007-030 ZANDZ Water-proof tape 2 0,442
15 GL-11075-10/20/50 GL-11075-10/20/50 GALMAR copper-bonded tape (30 * 4 mm / 120 mm²; 10/20/50-meters coil) 200
(in meters)

Appendix: the project is available in DWG and PDF formats

Appendix: the project is available in DWG and PDF formats-1

Appendix: the project is available in DWG and PDF formats-2

Files in the formats DWG and PDF are available for downloading only for authorized users. 



Do you need to make the project on grounding and lightning protection? Order it by contacting the ZANDZ Technical Center!

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