Moeller ps4-201-mm1, Hardware And Engineering

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Avoiding interference
31
04/
99 AW
B
27-
1184 G
B
Lightning protection
External lightning protection
All cables which are laid between two different
buildings must be screened. Metal conduits are
recommended for this purpose. Protective elements
against overvoltage, such as varistors or other types
of lightning arrester, should be used for signal
cables. The cables must be protected at the point at
which they enter the building, or at the latest at the
control cabinet.
Internal lightning protection
Internal lightning protection includes all measures
that reduce the effects of the lightning current and its
electrical and magnetic fields on the metal
installations and electrical systems inside a building.
These measures comprise:
Lightning-protection potential equalization
Screening
Overvoltage protection devices
Further information on this subject is provided in the
TB27-001GB manual from Moeller entitled
“Electromagnetic Compatibility (EMC) of Automation
Systems”.