Siemens Simatic 6ES7 157-0AC80-0 A0 Series, Manual

Page: 46 / 182

Wiring
4-4
DP/PA Link and Y Link Bus Couplings
A5E00193841-011
4.1.2 Operation with a grounded supply
Definition: Grounded supply
In grounded supplies, the neutral conductor is grounded. A simple short-circuit to
ground between a voltage-carrying conductor and ground or a grounded part of the
system leads to the protective devices being used.
Components and protective measures
Various components and protective measures are required for an overall system.
The type of components used and the degree to which the protective measures
are mandatory depend on which regulations (e.g. DIN VDE in Germany) are valid
for your system configuration.
Main switch (in Figure 4-2, ): DIN VDE 0100 Part 460
Isolator (in Figure 4-2, ): DIN VDE 0113 Part 1
Operation with a grounded supply
Figure 4-2 shows the position of the modules in the overall configuration when
power is supplied from a TN-S network. When the DP/PA coupler is configured
with a grounded reference potential, any interference current is discharged to the
protective conductor.
Note: The arrangement of the power connections shown does not correspond to
the actual arrangement on the modules; it was selected in the interest of clarity.