Siemens SIMATIC S7-1500 System Manual page 173

Overall configuration of S7‑1500R/H
The figure below shows the overall configuration of the S7-1500R/H redundant system (load
current supply and grounding concept) with supply from a TN-S network.
① Main switch
② Short-circuit and overload protection
Figure 7-1 Operating the S7‑1500R/H with grounded reference potential
NOTE
If you connect the S7-1500R/H redundant system via upstream local power supplies to your
own distribution (or batteries), then you do not have to provide any additional protective
measures against overvoltage.
S7-1500R/H redundant system
System Manual, 11/2022, A5E41814787-AD
7.2 Operation on grounded infeed
Wiring
173