A.5.3
Rules for the interfaces between Lightning Protection Zones 0 and 1
Rules for the lightning protection zone transition 0
A
to 1 (lightning protection equipotential bonding)
For lightning protection equipotential bonding at the interface of lightning protection zone
0
A
to 1, the following applies:
● No introduction of lightning component currents into buildings in hazardous areas. Sufficient
clearances of conductors and cables through which lightning current passes and that are
fed into hazardous areas.
● Define the zone transition 0
A
to 1 in the non-hazardous area.
Note
Since this zone transition is not relevant for the typical applications of the ET 200iSP, this
will be discussed in no further detail in this manual.
Rules for the lightning protection zone transition 0
B
to 1 (strong electromagnetic couplings)
For overvoltage protection at the interface of lightning protection zone 0
B
to 1, the following
applies:
● Use of power cables with peak current-capable cable shields (e.g., NYCWY) or twisted-pair
IT cables (for example, A2Y(K)Y).
● Laying cables and lines
– In continuous, peak current-capable metal pipes that are grounded at both ends, or
– In reinforced concrete channels in which the reinforcement is grounded at both ends, or
– On closed metal cable racks that are grounded at the beginning and end.
● Use of fiber optic cables without a metal shield if such a transmission is intended.
Other actions
If the actions listed above cannot be performed, protection by means of overvoltage
suppressors must be provided. The following table contains overvoltage suppressors that may
be used to protect facilities.
We recommend that three overvoltage suppressors for the signal cables and the 24 V supply
be integrated into an appropriate enclosure according to the specifications of the manufacturer
of the overvoltage suppressor. Refer to the "Enclosure specifications" in Chapter Application
example for protection of ET 200iSP from overvoltages (Page 362).
Note
To ensure the availability of a cable connection using overvoltage protection, both ends of the
cable must be connected to overvoltage suppressors.
Appendix
A.5 Lightning and overvoltage protection
ET 200iSP
Operating Instructions, 11/2017, A5E00247483-07
359
