Fields are used for growing various grain crops. The ZANDZ Technical Center received a request to calculate the lightning protection system for a field in Kursk. Normally, the lightning protection is not used in fields, but in this case, the customer asked to protect the 100 x 100 m field containing straw, according to Category I. Let us continue with more detailed review of our offered solution.
Calculation of lightning protection of a field in Kursk
Facility: a field in Kursk
Figure 1. Facility plan.
Task: to perform calculations for the lighting protection system in Kursk
Solutions to meet the requirements to the lightning protection system of the field in Kursk:
- The lightning protection is made in accordance with the Electrical Installations Code (EIC), Rev. 7, SO 153-34.21.122-2003 "Guidelines for the lightning protection of buildings, structures and industrial infrastructure" (hereinafter referred to as SO) and RD 34.21.122-87 "Guidelines for the lightning protection of buildings and structures" (hereinafter referred to as the RD).
- The lightning protection of the facility according to Category I is required as per regulatory documents, with reliability of 0.99.
- The facility's lightning protection is made using six wire lightning masts of 21 m high (ZZ-204-115), wire installation height is 20 m.
- For each lighting arrester, a grounding arrangement is installed as follows:
- Laying the horizontal grounding device for the current flowing in two directions. Length of each ground electrode is 5 m. The ground electrode is made of a corrosion-resistant steel copper-plated strip with a cross-section of 4 x 30 mm (GL-11075); the laying depth is 0.5 m.
- At the end of the horizontal ground electrode, one vertical electrode with the length of 3 m is installed in each direction.
- Vertical and horizontal electrodes, as well as horizontal electrodes with the interception rod are connected using clamps ZZ-005-064.
Results of the calculation performed using the software developed by the Krzhizhanovsky Energy Institute (OAO ENIN):
lightning discharge density into the ground is 4 strikes/square km per year.
Total number of strikes into the system is 0.19 (once per 5 years).
Total number of blowouts is 0.00095 (once per 1,053 years).
The probability of blowouts into the system's facilities is 0.00511.
System reliability is 0,9949.
На рисунке 2 показано расположение оборудования.
В таблице 1 приведен перечень необходимого оборудования и материалов.
Условные обозначения - Legend
Тросовый молниеприемник-мачта высотой 21 м (ZZ-204-120) - Wire lightning mast of 21 m high (ZZ-204-120)
Трос грозозащитный стальной оцинкованный (ZZ-204-001) - Ground wire steel zinc-plated (ZZ-204-001)
Полоса стальная омедненная сечением 30х4 мм (GL-11075) - Steel copper-plated strip with cross-section of 30 x 4 mm (GL-11075)
Зажим для подключения проводника (ZZ-005-064) - Wire clamp (ZZ-005-064)
Вертикальный заземлитель длиной 3 м - Vertical ground electrode of 3 m long
Figure 2 shows hardware layout.
Table 1 includes the list of required hardware and materials.
Do you have any questions about lightning protection of the field or other facilities? Please, contact the ZANDZ Technical Center!