Siemens Automation System S7-400 - Manual (Page 197)

Assembling and Installing Systems
A-29
Automation System S7-400 Hardware and Installation
A5E00850741-01
Components in figure A-7
The table A-6 explains consecutive numbers in the figure A-7:
Table A-6 Example of a Circuit Conforming to Lightning Protection Requirements
(Legend to Figure A-7)
Ser. No.
from fi-
gure A-7
Components Description
1 Lightning arrestor, depending on
the mains system, e.g. TN-S sy-
stem:
1 piece DEHNbloc/3,
order number: 900 110* and
1 piece DEHNbloc/1,
order number: 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 number: 900 600* High-voltage surge protection at transi-
tion 1 <--> 2
3 Surge arrestor,
Blitzductor CT type MD/HF,
order number: 919 506* and
919 570* Low-voltage surge protection for RS 485
interfaces at transition 1 <--> 2
4 Digital input modules:
FDK 2 D 60 V, order number:
919 993*
Digital output modules:
FDK 2 D 5 24 V, order number:
919 991*
Analog modules:
MD 12 V Blitzductor CT,
order number: 919 506 and
919 541
Low-voltage surge protection, signal mo-
dules I/O at transition 1 <--> 2
5 Bus cable shielding mounting de-
vice 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 mm Standardization of reference potentials
7 Blitzductor CT, type B for building
transitions;
order number: 919 506* and
919 510* High-voltage surge protection for RS 485
interfaces at transition 0 <--> 1
* You can order these components directly at: DEHN + SÖHNE
GmbH + Co. KG
Elektrotechnische Fabrik
Hans-Dehn-Str. 1
D-92318 Neumarkt