Siemens Simatic S7-300 CPU 31xC Series Installation And Operating Instructions Manual page 235

Low-voltage protection elements for 2 <-> 3
For the transition points between lightning protection zones 2 <-> 3 we recommend the
surge protection components listed in the table below. This low-voltage protection must be
used in S7-300 for CE compliance.
Table A-10 Surge-protection components for lightning protection zones 2 <-> 3
Conse Cables for ...
c. no.
1 3-phase TN-C system
3-phase TN-S system
3-phase TT system
AC TN-S system
AC TN-C system
AC TT system
2 24 VDC power supply
3 Bus cable
MPI, RS485
•
RS232 (V.24)
•
4 Inputs of digital modules
24 VDC
•
120 VAC
•
230 VAC
•
5 Outputs of digital modules 24 V
6 Outputs of analog modules up to
12 V +/-
* Please order these components directly from:
DEHN + SÖHNE
GmbH + Co. KG
Elektrotechnische Fabrik
Hans-Dehn-Str.
D-92318 Neumarkt
S7-300, CPU 31xC and CPU 31x: Installation
Operating Instructions, Edition 08/2004, A5E00105492-05
... equip transition point
2 <-> 3 with:
3 x DEHNguard 275 surge arresters
4 x DEHNguard 275 surge arresters
3 x DEHNbloc/275 surge arrester, phase
L1/L2/L3 to N
1 x N-PE surge arrester DEHNgap C
N to PE
2 x DEHNguard 275 surge arresters
1 x DEHNguard 275 surge arresters
1 x Surge arrester DEHNguard 275
phase L to N
1 x N-PE surge arrester DEHNgap C
N to PE
1 x Blitzductor VT, type AD 24 V
Blitzductor CT surge arrester, type
•
MD/HF
per cable pair
1 x •
Low-voltage surge protection FDK
2 12 V
1 x Low-voltage surge protection
Type FDK 2 60 V, on insulated rail
2 x Surge arrester
DEHNrail 120 FML
•
DEHNrail 230 FML
•
1 x Low-voltage protection FDK 2 D 5 24
1 x Low-voltage surge protection
Type FDK 2 12 V, on insulated rail
connected with M- of the power
supply for the modules.
A.3 Lightning and surge voltage protection
Order number
900 600*
5SD7 030
900 600*
5SD7 030
900 600*
5SD7 030
900 131*
900 600*
5SD7 030
900 600*
5SD7 030
900 600*
5SD7 030
900 131*
918 402*
919 506* and
919 570*
919 995*
919 993*
901 101*
901 100*
919 991*
919 995*
Appendix
A-25