Siemens ET 200S Manual page 99

24 VDC Supply
The following table tells you what you have to do with regard to the 24 VDC supply.
With ...
Buildings
24 VDC supply lines,
signal lines
24 VDC supply
Protection against Outside Electrical Influences
The following table tells you what to do to provide protection against electrical
influences or faults.
With ...
All plants or systems in
which the ET 200S is
integrated
Supply, signal, and bus
lines
Signal and bus lines
5.2 Operating the ET 200S on a Grounded Supply
In this section, you will find information on the overall setup of an ET 200S
distributed I/O system on a grounded supply (TN-S system). The specific subjects
discussed are:
S Circuit-breaking devices, short-circuit and overload protection in accordance
with DIN VDE 0100 and DIN VDE 0113
S Load power supplies and load circuits
Definition: Grounded Supply
In a grounded supply, the neutral conductor of the system is grounded. A mere
ground fault between a live conductor and ground or a grounded section of the
plant causes the protective devices to trip.
Distributed I/O System ET 200S
EWA 4NEB 780 6024-02 07
Pay Attention to ...
Outdoor lightning
protection
Indoor lightning
protection
Safe (electrical) isolation of extra-low voltage
You Must Ensure that...
The plant or system is connected to a protective
conductor for diverting electromagnetic interference.
The wiring arrangement and installation are correct.
Any break of a line or conductor does not result in
undefined states of the plant or system.
Wiring and Fitting
Take lightning protection
precautions
(for example, lightning
conductors)
5-3