Siemens Simatic S7-300, Hardware And Installation Manual, Page: 213 / 242

Appendix
S7-300 Programmable Controller Hardware and Installation
A5E00105492-01
11-25
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 11-10 Low-voltage protection for lightning protection zones 2 <-> 3
Ser.
No.
Cables for ... ... equip transition point
2 <-> 3 with:
Order No.
3-phase TN-C system 3 pieces
of DEHNguard 275 surge
arresters 900 600*
5SD7 030
3-phase TN-S system 4 pieces
of DEHNguard 275 surge
arresters 900 600*
5SD7 030
3 pieces
of DEHNbloc/275 surge arrester,
phase L1/L2/L3 to N 900 600*
5SD7 030 3-phase TT system
1 piece
of DEHNgap C, N-PE surge
arrester, N to PE 900 131*
AC TN-S system 2 pieces
of DEHNguard 275 surge
arresters 900 600*
5SD7 030
AC TN-C system 1 piece
of DEHNguard 275 surge
arresters 900 600*
5SD7 030
1 piece
of DEHNguard 275
surge arrester, phase L to N 900 600*
5SD7 030
1
AC TT system
1 piece
of DEHNgap C, N-PE surge
arrester, N to PE 900 131*
2 24 VDC Power Supply 1 piece Blitzductor VT, type AD 24 V - 918 402*
Bus cable
•
MPI, RS485
•
Blitzductor CT surge
arrester, type MD/HF
919 506* and
919 570*
3
•
RS232 (V.24) 1 piece
of
•
per conductor pair
Low-voltage protection
FDK 2 12 V 919 995*
Inputs of digital modules
•
24 VDC 1 piece
of Low-voltage protection, type
FDK 2 60 V, on insulated profile
rail 919 993*
2 pieces
of Surge arrester
•
120 VAC
•
DEHNrail 120 FML 901 101*
4
•
230 VAC
•
DEHNrail 230 FML 901 100*
5 Outputs of digital modules
24 V 1 piece
of Low-voltage protection
FDK 2 D 5 24 919 991*
6 Outputs of analog modules
up to 12 V +/- 1 piece
of Low-voltage protection,
type FDK 2 12 V, on insulated
rail connected with M- of the
power supply for the modules. 919 995*
* You can order these components directly from:
DEHN + SÖHNE, GmbH + Co. KG, Elektrotechnische Fabrik
Hans-Dehn-Str. 1, D-92318 Neumarkt