Siemens SIMATIC S7-1500 System Manual page 113

Redundancy scenario
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②
③
④
⑤
⑥
⑦
Figure 5-29 Failure of both redundancy connections and a PROFINET cable in the PROFINET ring
Sequence of events
1. Both redundancy connections (fiber-optic cables) fail in the redundant system. The time
between the failures is > 55 ms.
2. The redundant system switches to the RUN-Solo system state. The primary CPU remains in
the RUN operating state. The backup CPU switches to the STOP operating state.
3. A defective PROFINET cable also interrupts the PROFINET ring.
4. The redundant system accesses all IO devices in the PROFINET ring again over the
remaining PROFINET cables.
5. The redundancy of the system is restricted. The restrictions have no effect on the process.
S7-1500R/H redundant system
System Manual, 11/2022, A5E41814787-AD
Primary CPU
Backup CPU
Two fiber-optic cables (redundancy connections) → interrupted
IO device ET 200SP
IO device ET 200MP
PROFINET cable (PROFINET ring)
PROFINET cable (PROFINET ring) → interrupted
Application planning
5.4 Redundancy scenarios
113