Cables that must be routed in the ground must have a very robust construction. For this reason, ground routing should only use PROFIBUS cables approved by the manufacturer for routing in the ground.
In addition, the following is recommended for direct routing in the ground:
Route the PROFIBUS cable in a trench approximately 60cm below the surface.
Protect the PROFIBUS cable against mechanical damage, e.g. by using a plastic pipe. Place cable warning tape above it (approximately 20cm below the surface).
Route the equipotential bonding between the buildings approximately 20 cm above the PROFIBUS cable (e.g. galvanized ground strip). The ground strip is also used as protection against the effects of a lightning strike. The minimum cross section for the equipotential bonding according to IEC 60364-5-54 is:
Steel 50 mm²
Fig.: direct routing of PROFIBUS-cable in the ground
If several cables of different categories are routed in the same trench, maintain bricks as spacers.
Maintain a minimum distance of 30 cm to power supply cables up to a voltage of 1000 V, unless other regulations require a greater distance. Pertinent information about this topic can be found in EN 50174-3:2003. For higher voltages, please observe the corresponding standards and regulations.
During excavation, watch for indicators to other cables or devices (e.g. cable warning tape). Damage to another cable or device (e.g. power supply cables, gas lines) can lead to property damage as well as to risk of health and life
