Easy to design, the burying of electrical cables requires above all to respect the recommendations of standard NF C 15-100 to guarantee the safety of the installation.
Start by making a plan of the desired lighting. From there, position the trenches on the ground. This plan will also allow to re-intervene, if necessary, on the installation a few years later. The size of the trenches is calculated so that the electrical conduits are neither crushed nor damaged. Their depth must be 65 cm in current use and 85 cm under a driveway. A width of about 30 cm is enough.
In the vicinity of another buried electrical conduit, a water pipe, hydrocarbon, gas, etc., with or without crossing, a minimum distance of 30 cm must be respected.
The electrical conduits must be covered with a layer of sand and then with a piece of earth on which is placed a red or green warning grid. The latter is used to signal the presence of electrical circuits in case of further work on the area.
Install an electrical conduit in a trench
Dig a trench 30cm wide x 65cm deep.
Lay a layer of 10cm of sand.
Pull the cable into the sheath and place it in the bottom of the excavation.
Place a 5cm thick sand bed at the level of the sheath and then cover the whole with a second layer of sand on 10cm thick.
Place on the sand a layer of earth 20 to 30cm thick.
Then unfurl the fence over the entire length and width of the trench.
Finish by quenching the trench with a layer of 20cm of soil.
Do not hesitate to tamp it down to avoid too much later subsidence.
Install an electrical conduit under a driveway
Under a driveway, the depth of burial must be at least 85 cm to prevent crushing of electrical cables.
Again, do not forget the warning grill, designed to prevent accidental cutting during subsequent earthworks.