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Our company has built a new workshop but hasn’t installed grounding strips. Does anyone know how to install them and what the standards are?
You should refer to the standard \"Code for Design of Lightning Protection of Buildings (GBJ57-94)\\": Section 3 Grounding Devices, Article 4.3.1 Artificial vertical grounding electrodes buried in soil should preferably be made of angle steel, steel pipes, or round steel; Flat steel or round steel is suitable for artificial horizontal grounding electrodes buried in soil. The diameter of the round steel should not be less than 10 mm ; The cross-sectional area of the flat steel should not be less than 100 mm², and its thickness should not be less than 4 mm ; The thickness of the angle steel should not be less than 4 mm ; The wall thickness of the steel pipe should not be less than 3.5 mm. In soils with high corrosivity, anti-corrosion measures such as hot-dip galvanizing should be adopted or the cross-sectional area increased. The grounding wire should have the same cross-section as the horizontal grounding electrode. Article 4.3.2 The length of the artificial drop conductor to the ground shall be 2.5 m. The distance between artificial vertical grounding electrodes and the distance between artificial horizontal grounding electrodes should be 5 m; this distance can be appropriately reduced when subject to local constraints. Article 4.3.3 The burial depth of artificial grounding electrodes in the soil shall not be less than 0.5 m. The grounding electrode should be placed away from areas where the soil resistivity is increased due to high temperatures from brick kilns, flues, etc. Article 4.3.4 In areas with high soil resistivity, the following methods shall be employed to reduce the grounding resistance of lightning protection grounding systems: 1. Use a multi-wire external grounding system, where the length of the external wires shall not exceed the effective length; the effective length shall comply with the provisions in Appendix 3 of this code. II. The grounding electrode is buried in soil with a low resistivity at greater depths. III. Use a resistivity reducer. IV. Soil replacement. Article 4.3.5: The artificial grounding electrode for protecting against direct lightning strikes shall be at a distance of not less than 3 m from the building entrances, exits, or walkways. When it is less than 3 m, one of the following measures should be taken: 1. The horizontal grounding electrode should be buried locally to a depth of not less than 1 m ; II. The area of the horizontal grounding electrode should be covered with insulating material; an asphalt layer 50–80 mm thick can be used ; III. Use an asphalt-gravel surface, or apply an asphalt layer 50–80 mm thick on top of the grounding electrode; the width of this layer should be more than 2 m beyond the grounding electrode. Article 4.3.6 For grounding devices buried in soil, their connections shall be made by welding, and the welded areas shall be treated to prevent corrosion. Article 4.3.7 The calculation of the power-frequency grounding resistance of the grounding system shall comply with the provisions of the current **standard, namely the ‘Code for Design of Grounding in Electrical Installations’; the conversion between this value and the impulse grounding resistance shall follow the provisions in Appendix 3 of this code.
Based on what the poster has described, not only is the grounding device missing, but there is also no lightning protection system in place, right? It is recommended that you first classify the newly built buildings according to the requirements of GB50057-1994 \"Code for Design of Lightning Protection of Buildings\", carry out lightning protection design based on the corresponding category, and then install the appropriate lightning protection facilities as per the design