The ZANDZ Technical Center received a request for lightning protection of the funicular. Let’s see what should be protected.
The cable car cabin and the cable along which it moves are metal, so they themselves can act as lightning rods and down conductors. The cable must be grounded at the ends in the area of the sites (stations) so that there is room for the lightning current to drain. Such measures should ensure the safety of equipment, but despite this, it is forbidden to operate the funicular in a thunderstorm for the safety of people.
If lightning protection of the aerial part of the funicular is mainly provided by the design itself, the equipment of the drive (lower) and bypass (upper) stations is traditionally protected - with the help of rod lightning rods. Grounding devices serve both for grounding down conductors from lightning rods, and for grounding cables.
Learn more about the solution offered to our client from the news text.
Task
To calculate the lightning protection and grounding of the funicular.
Solution
The calculations of lightning protection of the funicular are made in accordance with the following documents:
- Electric Installation Code EIC 7-th ed.;
- IS 153-34.21.122-2003 «Instruction to lightning protection of buildings, structures and industrial communications» (hereinafter IS);
- AD 34.21.122-87 «Instruction on arrangement of lightning protection for buildings and structures» (hereinafter AD). Lightning rods are used to protect structures from lightning strikes. A lightning rod consists of a lightning rod, intercepting a lightning discharge, a down conductor and a ground electrode. All these elements allow you to safely drain lightning current into the ground without damage to the protected object.
The funicular refers to ordinary objects from the point of view of lightning protection in accordance with IS and to the 3rd category according to AD.
Description of the funicular lightning protection system
A set of measures to ensure the necessary requirements to a lightning protection system is represented by the following solutions:
- Installation of 4 rod lightning rods 1.5 m high, fixed to the wall at the top station and 3 of the same at the bottom. It was taken into account that 0.5 m of the height of the air terminal takes to fixation.
- Lightning rods are interconnected using a copper-bonded steel wire with a diameter of 8 mm for the organization of two down conductors from each lightning rod.
- The down conductors are mounted (installation step 0.6-1 m):
- to the wall with the help of GL-11703A clamps (for descent along the columns of the upper platform, 15 clamps per wall were taken into account, the bottom - 8 clamps per wall);
- on the roof with the help of GL-11747A clamps.
Connection and branching of down conductors is performed using GL-11551А clamps.
A set of measures to ensure the necessary requirements for the grounding device is represented by the following solutions:
- A grounding device is installed for each down conductor, consisting of a horizontal electrode (copper-bonded steel tape with a section of 4x30 mm), a depth of 0.5 meters and 2 vertical electrodes (copper-bonded steel rods with a diameter of 14 mm) 3 m long.
- The connection of the horizontal electrodes to each other is carried out using the ZZ-005-064 clamp.
- The connection of the down conductor with the output of the copper-bonded tape from the ground is carried out using the GL-11562A control clamp.
Figure 1. Plan for lightning protection and grounding of the lower station of the funicular
Figure 2. Plan of lightning protection and grounding of the upper station of the funicular
Components for lightning protection and grounding of the funicular
№ |
Product item |
Name |
Quantity, pc. |
Lightning protection system |
|||
1. |
GL-21134 |
GALMAR Air-terminal mast (1,5 meters; for vertical surfaces; galvanized streel |
7 |
2. |
GL-11149-50 |
2 |
|
3. |
GL-11703A |
45 |
|
4. |
GL-11747A |
50 |
|
5. |
GL-11551A |
GALMAR Clamp for connecting down conductors (painted galvanized steel) |
3 |
6. |
GL-11562A |
GALMAR Control clamp for connecting down conductors wire + tape (painted galvanized steel) |
4 |
Grounding device |
|||
7. |
ZZ-005-064 |
8 |
|
8. |
GL-11075-20 |
GALMAR Copper-bonded tape (30*4 mm/ S 120 mm²; coil of 20 meters) |
1 |
9. |
GL-11075-10 |
GALMAR Copper-bonded tape (30*4 mm / S 120 mm²; cil of 10 meters) |
1 |
10. |
ZZ-001-065 |
16 |
|
11. |
ZZ-005-064 |
9 |
|
12. |
ZZ-003-061 |
8 |
|
13. |
ZZ-004-060 |
4 |
|
14. |
ZZ-006-000 |
1 |
|
15. |
ZZ-007-030 |
3 |
|
16. |
ZZ-008-000 |
1 |
Do you have questions on grounding and lightning protection of a funicular? Contact ZANDZ Technical Center!
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