Application planning
6.4 Redundancy scenarios
6.4.7.8
Failure of a PROFINET line between two S2 devices in a line topology
Introduction
The following redundancy scenario describes the effects of a PROFINET line failure between
two S2 devices in a line topology.
Redundancy scenario
①
②
③
④
⑤
⑥
⑦
Figure 6-44
Sequence of events
1. The PROFINET line between the two S2 devices fails.
2. The redundant system will remain in the RUN-Redundant system state: The primary and
backup CPUs remain in the RUN-Redundant operating state.
3. The redundant system selects an alternative connection to the ET 200SP via the backup CPU.
This allows the redundant system to reach all IO devices in the line topology again.
4. The redundancy of the system is restricted. The restriction has no effect on the process.
If another system component or another network segment fails, the S7-1500R/H redundant
system will fail as a result:
If the PROFINET cable is also interrupted at another point in the line topology, an IO device
will fail.
196
Primary CPU
Backup CPU
Two fiber-optic cables (redundancy connections)
PROFINET cable (line topology)
IO device ET 200MP
IO device ET 200SP
PROFINET line (line topology) → interrupted
Failure of a PROFINET line between two S2 devices in a line topology
S7-1500R/H redundant system
System Manual, 01/2024, A5E41814787-AF