The grounding resistance of the high-voltage short-circuit grounding wire determines the quality of the grounding wire. Generally, according to the technical requirements of the power industry DL-T879-2004, the grounding wire resistance of each cross-sectional area is not greater than the following values:
DC resistance is measured between the wiring nose. For various sections of 16mm2, 25mm2, 35mm2, 50mm2, 70mm2, 95mm2, 120mm2, the average resistance per meter should be less than 1.24mΩ, 0.79mΩ, 0.56mΩ, 0.40mΩ, 0.28mΩ. , 0.21mΩ, 0.16mΩ.
High voltage grounding wire classification:
(1) The high-voltage grounding wire can be divided into: indoor busbar type grounding wire (JDX-NL) and outdoor circuit type grounding wire (JDX-WS) according to the use environment.
(2) The high-voltage grounding wire can be divided into 10KV grounding wire, 35KV high-voltage grounding wire, 110KV grounding wire, 220KV high-voltage grounding wire and 500KV high-voltage grounding wire according to the voltage level.