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¨ The complete system complies with the technical documen- 3.4.3 Documentation
tation, A report must be prepared for each inspection. This must be
¨ The complete external and internal lightning protection kept together with the technical documents and reports of pre-
system is in good order and condition, vious inspections at the installation / system operator´s prem-
¨ There are loose connections and interruptions in the con- ises or at the offices of the relevant authority.
ductors of the lightning protection system, The following technical documents must be available to the
inspector when assessing the lightning protection system:
¨ All earth connections (if visible) are in good order and con- Design criteria, design descriptions, technical drawings of the
dition, external and internal lightning protection system as well as
¨ All conductors and system components are properly in- reports of previous maintenance and inspection.
stalled and parts which provide mechanical protection are
in good order and condition, A report should contain the following information:
¨ Modifications requiring additional protection measures ¨ General: Owner and address, manufacturer of the light-
have been made to the protected structure, ning protection system and address, year of construction
¨ The surge protective devices installed in power installations ¨ Information on the structure: Location, use, type of
and information systems are correctly installed, construction, type of roofing, lightning protection level
¨ There is any damage or tripped surge protective devices, (LPL)
¨ Upstream overcurrent protective devices of surge protec- ¨ Information on the lightning protection system
tive devices have tripped, – Material and cross-section of the conductors
¨ Lightning equipotential bonding has been established for – Number of down conductors, e.g. test joints (designation
new supply connections or extensions, which have been according to the information in the drawing); separation
installed inside the structure since the last inspection, distance calculated
¨ Equipotential bonding connections are installed in the – Type of earth-termination system (e.g. ring earth elec-
structure and are intact, trode, earth rod, foundation earth electrode), material
and cross-section of the connecting lines between the
¨ Measures required for proximities between the lightning
protection system and installations have been taken. single earth electrodes
– Connection of the lightning equipotential bonding sys-
Measurements tem to metal installations, electrical installations and
Measurements are used to test the continuity of the connec- existing equipotential bonding bars
tions and the condition of the earth-termination system. ¨ Fundamentals of inspection
They must be made to check whether all connections of air- – Description and drawings of the lightning protection system
termination systems, down conductors, equipotential bonding – Lightning protection standards and provisions at the
conductors, shielding measures etc. have a low-impedance time of installation
continuity. The recommended value is < 1 Ω.
The contact resistance to the earth-termination system at all – Further fundamentals of inspection (e.g. regulations, re-
test joints must be measured to establish the continuity of the quirements) at the time of installation
lines and connections (recommended value < 1 Ω). Further- – Ex zone plan
more, the continuity with respect to the metal installations ¨ Type of inspection
(e.g. gas, water, ventilation, heating), the total earth resistance – Inspection at the design stage, inspection during the
of the lightning protection system and the earth resistance of construction phase, acceptance test, maintenance test,
single earth electrodes and partial ring earth electrodes must additional inspection, visual inspection
be measured. The results of the measurements must be com- ¨ Result of the inspection
pared with the results of earlier measurements. If they sig-
nificantly deviate from the earlier measurements, additional – Any modifications to the structure and / or the lightning
examinations must be performed. protection system
Note: In case of existing earth-termination systems which are – Deviations from the applicable standards, regulations,
older than 10 years, the condition and quality of the earthing requirements and application guidelines applicable at
conductor and its connections can only be visually inspected the time of installation
by exposing it at certain points. – Defects found

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