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Connection Concrete Fixed earthing terminal
Part No. 478 011
for the LPS
Perimeter
insulation Connecting clamp
Part No. 308 025
Soil

Foundation slab
Main earthing busbar (MEB)
Part No. 563 200 Reinforcement
MV clamp
Part No. 390 050

SV clamp
Part No. 308 229

Corrosion-resistant ring earth electrode, Functional equipotential Blinding
StSt (V4A) (e.g. material No. AISI/ASTM 316 Ti) bonding conductor layer

Figure 5.5.2.22 Arrangement of the foundation earth electrode in case of a closed floor slab (fully insulated) acc. to the German DIN 18014 standard

between 150 Ωm and 500 Ωm. This means that, in case of full This type of perimeter insulation is commonly used below
perimeter insulation, a foundation earth electrode convention- the floor slab and laterally at the basement wall. Apart from
ally arranged in the foundation has virtually no effect. Conse- its heat-insulating properties, foam glass gravel also has the
quently, the perimeter insulation acts as an electrical insulator. advantage that it is draining, capillary-breaking, load-bearing
and, compared to gravel, easy to transport. Before filling the
If the foundation slab and the outer walls are fully insulated
(full perimeter insulation), a ring earth electrode with an ad-
equate mesh size must be installed below the foundation slab
in the blinding layer or soil. This earth electrode must be made
of corrosion-resistant stainless steel (V4A), e.g. material No.
AISI/ASTM 316 Ti (Figure 5.5.2.22). As with “white tanks”, a
functional equipotential bonding conductor is required in this
case.

Capillary-breaking, poorly conducting floor layers
e.g. made of recycling material
Nowadays, recycling materials such as foam glass gravel or
other capillary-breaking materials are used as an alternative
to full perimeter insulation (Figure 5.5.2.23). These materials
are a cost-effective alternative to common polyurethane foam
sheets made of crude oil and serve as blinding layer (subgrade) Figure 5.5.2.23 Perimeter insulation: Foam glass granulate is filled in;
at the same time. source: TECHNOpor Handels GmbH

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