Appendix
A.3 Lightning and surge voltage protection
S7-300, CPU 31xC and CPU 31x: Installation
A-22
Operating Instructions, Edition 08/2004, A5E00105492-05
Consec.
no.
Cables for ...
... ... equip transition point 0 <-> 1 with:
Order number
2
24 VDC power supply
1 x
Blitzductor VT,
Type A D 24 V -
918 402*
3
MPI bus cable, RS485, RS232 (V.24)
1 x
Blitzductor CT lightning
conductor, type B
919 506* and
919 510*
4
Inputs/outputs of 24 V digital modules
DEHNrail 24 FML
909 104*
5
24 VDC power supply module
1 x
Blitzductor VT
Type A D 24 V -
918 402*
900 111*
5SD7 032
6
Inputs/outputs of digital modules and
120/230 VAC power supply
2 x
DEHNbloc/1 lightning conductor 900 111*
5SD7 032
7
Inputs/outputs of analog modules up to
12 V +/-
1 x
Lightning conductor
Blitzductor CT type B
919 506* and
919 510*
* You can order these components directly from:
DEHN + SÖHNE
GmbH + Co. KG
Elektrotechnische Fabrik
Hans-Dehn-Str. 1
D-92318 Neumarkt
A.3.4
Rules for the transition point between lightning protection zones 1 <-> 2 and
higher
Rules for transition points 1 <-> 2 and higher (local equipotential bonding)
The following measures must be taken on all transition points 1 <-> 2 and higher:
•
Set up local equipotential bonding at each subsequent lightning protection zone
transition.
•
Include all lines (also metal conduits, for example) in the local equipotential bonding of all
subsequent lightning protection zone transition points.
•
Include all metal installations located within the lightning protection zone in the local
equipotential bonding (for example, metal part within lightning protection zone 2 at
transition 1 <-> 2).
Additional Measures
We recommend fine-wire fusing for following elements:
•
All 1 <-> 2 and greater lightning protection zone transitions
•
All cables that run within a lightning protection zone and are longer than 100 m
Lightning protection element for the 24 VDC power supply module.
Always use the Blitzductor VT, type AD 24 V SIMATIC for the 24 VDC power supply module
of the S7-300. All other surge protection components do not meet the required tolerance
range of 20.4 V to 28.8 V of the S7-300 power supply.
