Classification and buried depth of electrical grounding body

Electrical grounding body can be divided into natural grounding body and artificial grounding body. This paper will introduce the classification and buried depth of electrical grounding body to help readers better understand the relevant knowledge of electrical grounding body.

Natural grounding body

Natural grounding bodies include: ① buried water pipes and other metal pipes (except liquid fuel and flammable and explosive gas pipes); (2) metal well tube; (3) Buildings, structures or underwater metal structures in contact with the ground; (4) Reinforced concrete foundation of buildings, etc.

Artificial grounding body

The artificial grounding body can be angle steel, round steel or steel pipe buried vertically, or round steel and flat steel buried horizontally. When the soil is highly corrosive, the surface of grounding body should be tinned or galvanized, and the cross section should be enlarged appropriately.

depth of burying

The buried depth of 25*4 flat iron used as grounding electrode for outdoor lighting is generally not less than 0.7m, and the top of artificial grounding body should be buried 0.5 ~ 1.5m below the ground surface. Below this depth, the soil conductivity has little change due to the seasonal influence, and the grounding resistance is stable and not easy to be damaged by external forces, which is determined according to the actual measurement.

earthing resistance

Generally, the grounding resistance shall not exceed 4 Ω, and the common grounding shall not exceed1Ω.