Portable Power Module for Güralp Certimus
Operation
4.2.2 Installation considerations
When planning the installation site, consideration should be give to possible
electrical storms, wind conditions, local temperature variations and incident light.
These are each discussed in the following sections.
4.2.2.1 Electrical storms
An exposed installation in a region affected by electrical storms requires some form
of lightning protection.
Warning:
Lightning strikes can cause lethal voltages, very high currents
and risk of fire. If in any doubt, seek professional advice when installing
in affected regions.
Caution:
No electrical equipment can withstand a direct hit from a
lightning strike. Even strikes some distance from the installation can
cause serious damage in two ways: induced currents in electrical
connections and voltage differences between ground points caused by
high currents flowing through the earth. In general, only partial
protection can be provided.
One method of partial protection consists of a lightning rod: a conductive target
mounted on a mast. The target is connected via a high-ampacity cable to a ground
point. In the event of a lightning strike, extremely high currents can flow to ground,
causing significant horizontal voltage gradients. For this reason, the grounding
point for the lightning rod should be as far as practical from the grounding point for
the seismic installation and the installation should have only one ground point.
A lightning rod provides a cone of protection with a radius equal to its height.
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Issue A - May 2021
