Connecting Non-Floating Or Floating Modules - Siemens S5-155U System Manual

Power Supplies for Programmable Controllers and I/Os
3.4.3
Connecting Non-Floating or
Floating Modules
Installation with
non-floating modules
Figure 3-11 Simplified Representation of an Installation with Non-Floating Modules
3 - 28
Shown in the following sections are the specical features when
installing non-floating and floating modules.
In an installation with non-floating modules, the reference potentials
of the control circuit (0 V
) and load circuits (0 V
int
connected.
The reference potential of the control circuit (0 V
PE or protective conductor terminal and must be connected to the
reference potential of the load circuit via an externally laid conductor.
Shown in the following figure is a simplified installation with
non-floating modules. The arrangement is independent of the
grounding concept. The connections for grounding are therefore not
drawn.
The voltage drop on line must not exceed 1 V. Otherwise there will
be a shift in reference potentials resulting in module malfunctions.
) are electrically
ext
) is given by the
int
System Manual
C79000-B8576-C199-03