Siemens ET 200S Manual page 100

Wiring and Fitting
Components and Protective Measures
Various components and protective measures are prescribed when setting up an
entire plant. The types of component and the degree to which the protective
measures are binding depend on the DIN VDE regulation that applies to your plant
setup. The following table refers to Figure 5-1.
Compare ...
Circuit-breaking device
for PLC, sensors and ac-
tuators
Short-circuit and overload
protection:
Grouped for sensors and
actuators
Load power supply for
AC load circuits with
more than five electroma-
gnetic devices
Safe Electrical Isolation
Safe electrical isolation must be provided for:
S Modules that must be supplied with v60 VDC or v25 VAC
S 24 VDC load circuits
Setting Up the ET 200S with Ungrounded Reference Potential
As of the IM151-1 BASIC (6ES7 151-1CA00-0AB0), IM151-1 STANDARD
(6ES7 151-1AA02-0AB0), IM151-1 FO STANDARD (6ES7 151-1AB01-0AB0) and
IM151-1 HIGH FEATURE (6ES7 151-1BA00-0AB0), the reference potential M of
the rated supply voltage for the IM151-1 is connected to the rail (protective
conductor) by means of an RC combination, therefore making an ungrounded
configuration possible.
To divert interference current, the reference potential of the IM151-1 is connected
internally to the rail (protective conductor) via an RC combination (R = 10 MΩ /
C = 22 nF). High-frequency interference currents are thus discharged, and static
charge is prevented.
5-4
Refer to DIN VDE 0100
Fig. 5-1


... Part 460:
Main switch

... Part 725:
Single-pole pro-
tection of circuits


Isolation by trans-
former recom-
mended

DIN VDE 0113
... Part 1:
Disconnector
... Part 1:
S
With a grounded
secondary circuit:
single-pole protection
S
In all other cases: all-pole
protection
Isolation by transformer re-
commended
Distributed I/O System ET 200S
EWA 4NEB 780 6024-02 07