1. Except for the independent grounding requirements of the independent lightning rod and overhead lightning line (network) grounding device in the first type of lightning protection building, other buildings should use natural components such as metal supports, metal frames or reinforced concrete reinforcement, metal pipelines, and protective wires (PE) of low-voltage distribution systems inside the building to connect with external lightning protection devices to form a shared grounding system. When there are power and communication cables connected between adjacent buildings, it is advisable to connect their grounding devices to each other
2. The spacing distance between the independent lightning rod and overhead lightning line (network) pillars and their grounding devices of the first type of lightning protection building, as well as the metal objects such as the protected object and the pipes, cables, etc. connected to them, should comply with the provisions of Article 4.2.1 (5) of GB50057-2010 When using the foundation steel bars of buildings as grounding devices, they should comply with the provisions of 4.3.5, 4.4.5, and 4.4.6 in GB50057-2010 4. The grounding resistance (or impulse grounding resistance) values of various lightning protection building grounding devices should comply with the requirements of Chapter 4 of GB50057-2010. The design requirements specified in other industry standards are shown in the table below
Main body of grounding device
Allowable value/Ω
Main body of grounding device
Allowable value/Ω
Automotive refueling and gas station
≤ 10
Weather radar station
≤ 4
Electronic information system room
Distribution electrical device (Class A)
or distribution transformer (Class B)
≤ 4
Satellite Earth station
≤ 5
Mobile base station
≤ 10
; Note 1: When using a shared grounding device for lightning protection, anti-static grounding, electrical equipment working grounding, protective grounding, and information system grounding of refueling and gas stations, the grounding resistance should not exceed 4 Ω
Note 2: The electronic information system room should share a set of grounding devices for AC working grounding (required ≤ 4 Ω), AC protective grounding (required ≤ 4 Ω), DC working grounding (determined according to the specific requirements of the computer system), and lightning protection grounding. The grounding resistance should be determined according to the minimum value among them
Note 3: When the soil resistivity of the common grounding device for radar stations is less than 100 Ω • m, it should be ≤ 1 Ω; When the soil resistivity is between 100 Ω• m and 300 Ω• m, it should be ≤ 2 Ω; When the soil resistivity is between 300 Ω• m and 1000 Ω• m, it should be ≤ 4 Ω; When soil resistivity> At 1000 Ω • m, the requirements can be relaxed appropriately
5. The material, burial depth, and spacing requirements of artificial grounding bodies should comply with the provisions of 5.4.1 to 5.4.7 in GB50057-2010 6. The measurement of soil resistivity shall comply with the provisions of Appendix B According to the provisions of 4.2.4, 4.3.6, and 4.4.6 of GB50057-2010, when the grounding devices of Class I, II, and III lightning protection buildings have small radii such as the grounding grid greater than the specified value under certain soil resistivity conditions, no artificial grounding body can be added, and the impact grounding resistance value can be ignored
8. The anti step voltage should comply with the provisions of 4.5.6 in GB50057-2010 9. When lightning protection buildings of the second and third categories are subjected to high potential counterattacks, the spacing distance should comply with the provisions of 4.3.8 and 4.4.7 in GB50057-2010
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