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vertical box section
wall mounting
bracket
expansion joint

horizontal support

expansion joint

Fixed earthing terminal Bridging braid Bridging braid
Part No. 478 200 Part No. 377 115 Part No. 377 015

Figure 5.2.2.2.1 Use of natural components – New buildings made Figure 5.2.2.2.2 Metal substructure, conductively bridged
of ready-mix concrete

Figure 5.2.2.2.3 Earth connection of a metal Figure 5.2.2.2.4 Down conductor installed Figure 5.2.2.3.1 Test joint with number plate
façade along a downpipe

¨ Interconnected reinforcement of the structure ¨ Façade elements, DIN rails and metal sub-struc-
The reinforcement of existing structures cannot be used tures of façades
as a natural component of the down conductor unless the These components can be used as natural down conduc-
reinforcement is safely interconnected. Separate external tors provided that the dimensions meet the requirements
down conductors must be installed. for down conductors (5.6.2 of IEC 62305-3 (EN 62305-3))
¨ Precast parts and that the thickness is at least 0.5 mm for sheet metal
Precast parts must be designed to provide connection and metal pipes and their conductivity in the vertical di-
points for the reinforcement. They must have a conductive rection meets the requirements of 5.5.3 of IEC 62305-3
connection between all connection points. The individual (EN 62305-3).
components must be interconnected on site during instal- Note: In case of prestressed concrete, the particular risk of
lation (Figure 5.2.2.2.1). possible impermissible mechanical effects due to the lightning

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