Non-Floating And Floating Configurations - Siemens SIMATIC S5-100U System Manual

S5-100U
3.3.3

Non-Floating and Floating Configurations

The S5-100U is powered by its own control circuit. The I/Os are powered by the load circuit.
The circuits can either be connected to the same grounding point (non-floating) or galvanically
isolated (floating).
Example of a Non-Floating Connection of Digital Modules
A 24 V DC load circuit has the same chassis grounding as the control circuit of the CPU.
Central
grounding point
Common
chassis ground
Load power
supply
Figure 3-21. Example: Non-Floating Connection of I/Os to the S5-100U
EWA 4NEB 812 6120-02b
PS CPU
L+
M
M L+
Installation Guidelines
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