1. The cable line can be concealed laid, also exposed installation. The concealed cable can be laid along the cable tunnel or cable trench, or it can be buried directly underground. Compared with overhead lines, the safety performance of buried cable lines is good, but installation costs are high.
2. There must be a certain distance between the cables and the cables and pipes or other underground buildings. Otherwise, accidents may occur due to the electric leakage of the cable sheath and the hazard maintenance due to too small distance. For buried cables, must be drawn a plan and the data should be kept, and marks shall be set where necessary. In order to prevent mechanical damage, when voltage over 1000V, the armored cables should be used, and the radius should not be too small when bending.
3, indoor cable lines should be exposed installation as far as possible, Pipes shall be put through when buried underground. The distance between the indoor cable and the heat pipe shall not be less than 1m. Otherwise, insulation shall be added; the distance between the cable and other pipes shall not be less than 0.5m; otherwise, appropriate protective measures shall be taken; the distance between the low voltage cables is generally Not less than 35mm; the distance between high and low voltage cables is generally not less than 150mm.
Permissible distance when burying cables and pipelines when approaching or crossing (unit: meter)
|Category||Close distance||Vertical distance when crossing|
|Cables and flammable pipes||1.0||0.5|
|Cable and thermal ditch||2.0||0.5|
|Cable and thermal ditch||0.6||-|
|Cables and poles||0.5||-|
|Cables and trees||1.0||-|
|Cables and other pipes||0.5||0.25|
|Cable and railway subgrade||3.0||1.0|
4. For the inspection and maintenance of buried cable lines, in order to prevent residual charges from hurting people, they should be discharged first. Discharge should also be performed after the insulation test.