Underground electrical installations
Electrical installations buried underground
Sound underground cable protection requires first and foremost safe and absolutely reliable products. Especially the energy consumption of outdoor facilities has changed drastically over the last years. Nowadays, flexible energy options are needed for, let's say, Christmas lighting, pond pumps, fountains, audio systems which are installed with the help of cable conduits.
Along with mere mechanical protection, cable conduits enable quick and easy allocation of various media used above ground. Another practical advantage especially for electrical installations: cable conduits do more than just protect. At the same time, they can be used as conduits to allow easy retrofit insertion of additional cables and wires.
Standards and provisions
Conduits are considered electrical equipment and are subject to the Low Voltage Directive.
All electrical equipment subject to the Low Voltage Directive must bear the CE Marking.
In order to comply with the safety requirements of the Low Voltage Directive, DIN VDE and DIN product standards and erection regulations must be complied with.
DIN VDE 0100-520
Low-voltage electrical installations - Part 5: Selection and erection of electrical equipment; chapter 52: Wiring systems
• This part 520 of the standards of the DIN VDE 0100 (VDE 0100) series outlines the selection and erection of wiring systems.
• Minimum requirements for the point of installation.
The amendment of the standard of 01 July 2013 means:
• the end of flame-propagating conduits
• the end of pliable, resilient conduits in concrete
• a new test method for zero halogen conduits
For more information on standards, please see our conduit guide for experts.
DIN EN 61386-1 (VDE 0605-1)
Conduit systems for cable management – Part 1: General requirements
• This standard defines requirements and tests relating to conduit systems, including conduits, conduit fittings and accessories, for the protection and routing of insulated wires and cables in electrical installations or in communication systems up to 1,000 V a.c. and/or 1,500 V d.c.
• Conduit classification codes
DIN EN 61386-24
Conduit systems for cable management - Part 24: Particular requirements - Conduit systems buried underground
Conduit swale and bearing
In case of rocky or stony ground, a stoneless cover (sand, fine gravel) is required as lower bedding (see DIN EN 1610 and KRV A 535).
Backfill and compact cable conduit up to 30 cm above the conduit crown by hand with stoneless, compactable soil.
Provide for measures against mechanical deflection in case of less than the minimum cover.
Kabu-Seal is a pressure sealing ring made of a solid rubber core with a soft thermoset elastomer jacket. Using compression flange connections, the soft surface forms a seal between the cable conduit and the core drill hole of up to 1.5 bar water pressure.
The EPDM wall collar is used to seal Kabuflex® conduits routed through foundation slabs
and concrete walls. The circular wall collar with profiled ridges is mounted onto the conduit under initial tension and attached to the conduit using a steel tightening strap system.