Electricity + Control October 2015

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take note
Trevor Manas started his lightning protection career at Pontins
in 1991 as an installation technician. Within two years, he
was promoted to a sales engineer position. In 1996, he was
promoted to the position of director and was in charge of
ensuring the company`s compliance with the earthing and
lightning protection codes of practice. In 1999, Trevor became
the managing director of Pontins. Enquiries: Email
EARTHING + LIGHTNING PROTECTION
In many cases, we have found that substandard (Grade ‘B’) earth elec-
trodes with a copper cladding of 40 microns are being used by many
installers of earthing and lightning protection systems. This practice
is non-compliant and should be avoided at all costs. A specimen of
two coupled rods undergo an ‘Impact Test’ by means of a vibration
hammer with a blow rate of 2 000 ± 1 000 min with a kinetic energy of
impact 50 ± 10 (Nm) is applied to the top of the rod. If the rods or the
couplings pass the above test without visible defects, they are sub-
jected to artificial ageing and are loaded with three lightning current
impulses of wave shape 10/350 μs of 50 kA and 100 kA each. In order
to pass the test the transition resistance (via the coupling) must not
exceed 2,5 mΩ. After the lightning impulse test the coupling is then
subjected to a tensile strength test to determine whether or not the
connection is sufficiently strong after the induced lightning currents.
Conclusion
The installation of a functional lightning protection system requires
that the components and devices are tested in accordance with the
latest standards. Only lightning protection systems that comprise
components that are manufactured and tested in accordance with
the SANS / IEC 62561 [2] series of standards can be considered to be
compliant. Manufacturers` test reports must accompany all lightning
protection system certification.
References
[1] SANS/IEC 62305. Lightning Protection Standard (LPS) series.
[2] SANS/ IEC 62561: Lightning Protection SystemComponent (LPSC)
series.
Bibliography
DEHN Lightning Protection Guide 3rd Edition.
DEHN Lightning Protection / Earthing Catalogue - January 2015
edition.
• Components and devices in functional lightning
protection systems must be tested according to the
latest standards before installation.
• Only components and devices tested in accordance
with SANS/IEC 62561 are considered to be compli-
ant.
• Manufacturers’ test reports must accompany all
lightning protection system certification.
Testing of LPS components.
MV clamp for a test
in the impulse current
laboratory.
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