Siemens SIMATIC ET 200iSP Operating Instructions Manual page 357

Effects of a Lightning Stroke
Direct lightning strikes occur in lightning protection zone 0
high-energy lightning currents and strong electromagnetic fields. Because direct lightning
strikes occur only in lightning protection zone 0
not examined here.
Only the lightning protection zone transitions from 0
Effects must be reduced from one lightning protection zone to the next through suitable
lightning current or combination suppressors or shielding measures.
As described in the EN 1127-1 standard, direct lightning strokes ignite explosive atmospheres.
Therefore, continuously active lightning protection systems are prescribed for such facilities
according to the current lightning protection standards.
Overvoltages
Electromagnetic fields of the lightning channel can be reduced with appropriate shielding
measures. Overvoltages due to inductions can be reduced to an non-dangerous level starting
in lightning protection zone 0
ET 200iSP
Operating Instructions, 11/2017, A5E00247483-07
(as described in the next chapter), these are
A
B
using overvoltage suppressors.
B
A.5 Lightning and overvoltage protection
. Effects of the lightning strike are
A
to 1 and higher are examined.
Appendix
357