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Figure 9.22.2 Lightning equipotential bonding by means of Figure 9.22.3 DEHNconductor HVI light Conductor
DEHNventil M

the entry point of the main low-voltage distribution board
by means of a DEHNventil combined arrester. The associated
lightning equipotential bonding system for metal and electron-
ic systems additionally prevents fire in these structures.

Isolated air-termination system
According to the latest lightning protection standards, isolated
air-termination systems are to be used to protect metal flood-
light pylons, parts of the spectator gallery, scoreboards and
flagpoles against direct lightning strikes. These parts are con-
ductively connected with sensitive electrical / electronic equip-
ment via electrical lines. Isolated air-termination systems such
as the DEHNconductor HVI system (high-voltage-resistant,
insulated conductor, Figure 9.22.3) prevent flashover. Con-
sequently, no lightning currents will travel through the metal
floodlight pylons, scoreboards, parts of the spectator gallery
and flagpoles, thus preventing dangerous lightning currents
from flowing into sensitive electrical systems. Figure 9.22.4
shows a DEHNconductor HVI system installed on a pylon. The
height of the air-termination tip depends on the relevant class
of LPS, which must be determined in advance. The high-volt-
age-resistant, insulated down conductor (HVI Conductor) can Figure 9.22.4 HVI Conductor installed at a pylon
be directly installed at the pylon in line with the installation
instructions using system-specific accessories. Thus, lightning
currents do not enter the pylon and the electrotechnical instal- bonding and the efficiency of the individual foundation earth
lation. electrodes. If correctly installed, they form a protected volume
in case of a direct lightning strike to the cable routes of the
Lightning protection for floodlights floodlight (Figure 9.22.5).
Floodlights next to the sideline or spectator galleries should
be provided with a lightning protection system. The earth- Standing surface insulation, touch and step voltage
termination systems of the individual pylons should be con- (potential control)
nected to one another and to the earth-termination systems Persons standing directly next to lightning current carrying
of the sports buildings (club houses, locker rooms or technical floodlight pylons, fences, flagpoles or covered stands during
buildings). These additional connections improve equipotential a lightning strike bypass high potential differences with their

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