When the grounding module is constructed vertically, trenches should be dug at the location where the grounding module needs to be buried according to the design drawings. The diameter of the trench should be convenient for placing the grounding module, and the depth should be the burial depth of the horizontal grounding body plus the length of the grounding module.
The connection between the galvanized steel metal electrode core of the module and the steel grounding body should be welded. The welding joint should be cleaned of welding slag and given corresponding anti-corrosion treatment. When connecting the copper metal electrode grounding module to the copper grounding body, special exothermic welding technology can be used. See the "Exothermic Welding" section for details. Special hardware can also be used for connection, and lock nuts and lock washers can be installed.
When multiple grounding modules are arranged on the grounding body, the distance between each two modules is 3 to 5m. On the extended ray grounding body of mountainous lines, the distance between every two pieces should be greater than 5m.
When the grounding resistance requirement is not high and the soil resistivity is less than 1000Ω·m. Deep buried grounding can be used, and the grounding body and grounding module are directly buried under the tower foundation. This can reduce land acquisition costs, and the grounding module is less affected by seasonal factors.
When constructing the grounding module horizontally, dig a trench at the location where the grounding module needs to be buried according to the design drawings. The length and width of the trench should be convenient for placing the grounding module, and the depth should be the same as the burial depth of the horizontal grounding body.
During the laying process of the grounding module, about 10cm thick fine soil should be laid on the bottom of the pit, and then the fine soil covering the module should be backfilled to about 10cm thick. If there is no backfilling fine soil on site, the fine soil should be backfilled first, and the gravel excavated from the trench should be backfilled last. The backfilling process should be compacted layer by layer.
Grounding modules used in substations should be evenly arranged in the station area. In large substation grounding grids, grounding modules should be distributed in the main equipment area of the peripheral station area of the grounding grid. The spacing between modules is preferably 5m to 10m.
