Siemens S5-155U System Manual page 60

Interference-Free Installation of Centralized and Distributed Interface Circuits
CC
Figure 3-13 Shielding and Grounding the Connecting Cable
Special features
System Manual
C79000-B8576-C199-03
With distributed interfacing (IM 304/IM 314 and IM 301/IM 310),
ensure that the VDE specifications for laying the protective ground are
complied with; distributed interfacing is non-floating.
The measures described above are shown in the following figure. If
the permissible potential difference between ground points can be
exceeded, you must install an equipotential bonding conductor
(cross-section ≥ 16 mm 2
of copper).
With distributed interfacing, you must use the prefabricated
connecting cables. You may have excess lengths of up to 100 m when
installing the connecting cable. These excess lengths must be
bifilar-wound and deposited at a point which is protected from
electromagnetic interference.
EU
Shield/Protective
Conductor Bar
3
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