Failure scenario
① Primary CPU → failed
② Backup CPU → becomes new primary CPU
③ Two fiber-optic cables (redundancy connections)
④ PROFINET cable (PROFINET ring 1)
⑤ PROFINET cable (PROFINET ring 2)
⑥ IO device ET 200SPHA (R1 device)
⑦ IO device ET 200SP (R1 device)
⑧ IO device ET 200pro (S1 device) → no longer accessible, because PROFINET ring 1 assigned
⑨ IO device ET 200SP (S2 device, reparameterized to an S1 device) → no longer accessible,
because PROFINET-Ring 1 assigned
⑩ IO device ET 200SP (S2 device, reparameterized to an S1 device)
⑪ IO device ET 200pro (S1 device)
Figure 5-46Primary CPU failure in PROFINET rings with R1 and S1 devices
Sequence of events
1.
The primary CPU of the redundant system fails in RUN-Redundant system state.
2.
The redundant system switches to the backup CPU. The backup CPU becomes the new
primary CPU. The redundant system switches to the RUN-Solo system state.
3.
The R1 and S1 devices in PROFINET ring 2 can still be accessed via the new primary CPU.
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Application planning
5.5 Failure scenarios
S7-1500R/H redundant system
System Manual, 11/2022, A5E41814787-AD