# LIGHTNING PROTECTION OF A PARK

Walking in the part do you think of what could happen if a storm starts? Will you be protected from lightning? Everybody knows that a tree won't protect from lightning, because being a good conductor and in case of a lightning strike, a person standing near will probably be hit by a step voltage.

ZANDZ Technical Center received a request for the development of lightning protection system for a park including the trees. Engineers calculated such a lightning protection system and further we will study the offered solution.

Initial data:

• park sizes: 180 m x 120 m;

• height of the protected area (including the trees): 40 m.

Calculate external lightning protection system of a park.

Solution:

Lightning protection and grounding of a park are performed in accordance with:

The object refers to III category of lightning protection in accordance with AD and to "ordinary" in accordance with IS.

The set of measures on the provision of the necessary requirements to the lightning protection of the park is presented by the following solutions:

1. Lightning protection of the park is implemented with the help of lightning rods ZZ-201-055.

2. The structure of the grounding device for each mast is carried out in accordance with AD item 2.26.

3. 2 copper-bonded steel electrodes 3 m long for one base are used as a vertical ground electrode. The distance between the electordes is at least 5 m. Copper-bonded steel tape with the cross-section of 30x4 mm (GL-11075) is used as a horizontal ground electrode. The burial depth is 0.5 – 0.7 meters.

4. Connection to the grounding device is carried out with the help of clamps ZZ-005-064.

Results of the calculation carried out with the software developed by the JSC "Energy Institute to the name of G.M. Krzhizhanovsky (JSC "ENIN"):

• the density of lightning strikes into the ground - 6 strikes / sq. km per year;

• the total number of strikes into the system: 1.15;

• total number of lightning breakthroughs – 0.03;

• probability of breakthrough into all the system objects - 0.026;

• system reliability – 0,974;

• the average time between lightning strikes into the system (years): 1;

• average time between the breakthroughs, bypassing the protection (years): 33;

Equipment arrangement layout is shown in figure 1.

Figure 1 - Layout of equipment arrangement of lightning protection for a park.

The list of equipment is given in Table 1.

Table 1 - List of equipment and materials.

 № Product item Name Quantity, pcs. Mass, kg Note 1. ZZ-201-055 ZANDZ Vertical lightning rod 55 m (galvanized steel; with embedded fittings for placing under the foundation) 5 5000 2. GL-11075-20 GALMAR Copper-bonded tape (30 * 4 mm / S 120 mm²; coil of 20 meters) 2 0,98 In coils 3. ZZ-001-065 ZANDZ Copper-coated threaded grounding rod (D14; 1.5 m) 20 2,00 4. ZZ-002-061 ZANDZ Threaded coupler 11 0,08 5. ZZ-003-061 ZANDZ Starting tip 10 0,07 6. ZZ-004-060 ZANDZ Driving head for a jackhammer 4 0,09 7. ZZ-005-064 ZANDZ Clamp for connecting conductor (up to 40 mm) 16 0,312 8. ZZ-006-000 ZANDZ Conductive grease 1 0,10 9. ZZ-007-030 ZANDZ Waterproof tape 4 0,15 10. ZZ-008-000 ZANDZ Header for a jackhammer (SDS max) 1 0,50

Do you have questions or you need to calculate lightning protection and grounding for a park? Send your request to info@zandz.ru.