When erecting new objects, it is necessary to perform lightning protection and grounding, especially if we are talking about industrial buildings.
ZANDZ Technical Center accepted an inquiry for the calculation of lightning protection and grounding system of a pre-installation preparation warehouse. The task solution was as follows:
sizes: 106 m x 116 m;
walls and roof materials: wall and roof sandwich panels;
soil resistivity: 100 Ohm * m.
Lightning protection and grounding of a pre-installation preparation warehouse are performed in accordance with:
The set of measures on the provision of required lightning protection and grounding measures of a gas distribution plant is presented by the following solutions:
The object refers to category 3 of lightning protection.
According to IS 153-34.21.122-2003, paragraph 22.214.171.124, the metal roof of the object (roofing sandwich panel) is used as a lightning rod.
Wall sandwich panels are used as down conductors.
Transient resistance between all metal sheets and panels must be not more than 0,05 Ohm at an obligatory annual control before the storm season in accordance with AD 34.21.122-87, item 3.4.
All metal elements placed on the roof must be attached to the metalwork of the object.
All reinforced concrete foundations, plinths should be used as natural ground electrodes and be attached to the artificial grounding device.
Copper - coated steel electrodes 3 m long are used in places of downdrops as a vertical ground electrodes.
Copper-bonded steel tape with the cross-section of 30x4 mm in the form of a circuit is used as a horizontal ground electrode РД 34.21.122-87, п.2.26. The distance to the object foundation- not less than 1 m. Burial depth of the tape 0,5-0,7 m.
Connection to the grounding device is carried out with the help of clamps ZZ-005-064.
In accordance with the EIC-7 ed., P.1.7.55 - Grounding devices for protective grounding of electrical installations of buildings and structures and lightning protection of the 2nd and 3rd categories of these buildings and structures, as a rule, should be common.
Grounding device resistance calculation:
The calculation method is given on page.
The design resistance of the grounding device is 1,2 Ohm.
Equipment arrangement layout is shown in figure 1
Figure 1 - Arrangement of lightning protection and grounding equipment of a pre-installation preparation warehouse.
Полоса стальная омедненная – copper-bonded steel tape
Зажим для соединения проводников – Clamp for connecting conductors
Вертикальный заземлитель длиной 3 м – Vertical ground electrode 3 m long
The list of equipment is given in Table 1.
Table 1 - Materials requirement list.
|№||Product item||Name||Quantity, pcs.||Mass, kg||Note|
|1.||GL-11075-50||GALMAR Copper-bonded tape (30 * 4 mm / S 120 mm²; coil of 50 meters)||6||0,98||In coils|
|2.||ZZ-001-065||ZANDZ Copper-bonded threaded grounding rod (D14; 1.5 m)||24||2,00|
|3.||ZZ-002-061||ZANDZ Threaded coupler||13||0,08|
|4.||ZZ-003-061||ZANDZ Starting tip||12||0,07|
|5.||ZZ-004-060||ZANDZ Driving head for a jackhammer||5||0,09|
|6.||ZZ-005-064||ZANDZ Clamp for connecting conductors (up to 40 mm)||31||0,312|
|7.||ZZ-006-000||ZANDZ Conductive grease||2||0,15|
|8.||ZZ-007-030||ZANDZ Waterproof tape||8||0,4|
|9.||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 pre-installation preparation warehouse? Send your request to firstname.lastname@example.org.