Siemens Simatic S7-300, Hardware And Installation Manual, Page: 215 / 242

Appendix
S7-300 Programmable Controller Hardware and Installation
A5E00105492-01
11-27
Components in previous figure 1-2
The table below explains consecutive numbers in the figure above:
Table 11-11 Example of a circuit conforming to lightning protection requirements (legend to
previous figure)
Ser. No.
from the
previous
figure
Components Description
1 lightning arrestor, depending on the
mains system, e.g. TN-S system:
1 piece DEHNbloc/3,
Order No.: 900 110* and
1 piece DEHNbloc/1,
Order No.: 900 111* High-voltage protection against
direct lightning strike and surge
voltage as of transition 0 <-> 1
2 surge arrestors,
2 pieces DEHNguard 275;
Order No.: 900 600* High-voltage surge protection at
transition 1 <-> 2
3 Surge arrestor,
Blitzductor CT type MD/HF;
Order No.: 919 506* and 919 570* Low-voltage surge protection for
RS485 interfaces at transition
1 <> 2
4 Digital input modules:
FDK 2 D 60 V; Order No.: 919 993*
Digital output modules: FDK 2 D 5, 24
V; Order No.: 919 991*
Analog modules:
MD 12 V Blitzductor CT;
Order No.: 919 506 and 919 541
Low-voltage surge protection,
signal modules I/O at transition
1 <-> 2
5 Bus cable shielding mounting device
with EMC spring clamp on the basic
unit of Blitzductor CT; Order No.:
919 508* Discharge of interference current
6 Cable for equipotential bonding: 16 sq.
mm Standardization of reference
potentials
7 Blitzductor CT, Type B for building
transitions;
Order No.: 919 506* and 919 510* High-voltage surge protection for
RS485 interfaces at transition 0 <-
> 1
* You can order these components directly from:
DEHN + SÖHNE
GmbH + Co. KG
Elektrotechnische Fabrik
Hans-Dehn-Str. 1