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air-termination system
+ HVI Conductor r = 30 m
stainless steel GRP / Al supporting tube
chimney
blowout
s

earth or EB connection
(Ø 8.4 mm) 3.2 m
EBB
MEB
HVI Conductor

Components Part No.
HVI Ex W70 holder 275 440 concrete base

HVI Ex W200 holder 275 441
base plate
HVI Ex busbar 500 275 498

Earthing busbar (2 x 2 terminals) 472 109
Components Part No.
Figure 9.33.4 Isolated external lightning protection system for a flat
roof HVI Conductor I integrated in the support- 819 320
ing tube with air-termination tip
Tripod for HVI Conductor integrated in the
Internal lightning protection – Lightning equi- supporting tube 105 350
potential bonding – Surge protection
All conductive systems entering the gas pressure control and Concrete base 102 010
measurement system from the outside must be integrated in Base plate 102 050
the lightning equipotential bonding system (Figure 9.33.6).
This is achieved by directly connecting all metal systems and Figure 9.33.5 Isolated external lightning protection system for a flat
indirectly connecting all live systems via surge protective roof - Installation option 3
devices. These surge protective devices must be capable of
discharging lightning currents (type 1 SPD: test wave form Additional protection measures as per IEC 62305-4
10/350 µs). Lightning equipotential bonding should be estab- (EN 62305-4) for increasing the availability of sensitive elec-
lished as close as possible to the entry point into the struc- trical systems may be required depending on the immunity
ture (zone transition from LPZ 0 to 1 or higher) to reduce high level and installation environment of the systems. A com-
potential differences and dangerous sparkover in potentially bination of surge protection, shielding and supplementary
explosive atmospheres and to prevent partial lightning cur- equipotential bonding measures have proven their worth in
rents from entering the structure. practice.

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