Overview of system and operating states
The figure below shows the possible operating states of the CPUs and the resulting system
states.
In general, the two CPUs have equal priority; each CPU can be either primary or backup.
The CPU that you switch from STOP to RUN first becomes the primary CPU.
Figure 9-6
System and operating states
S7-1500R/H redundant system
System Manual, 10/2018, A5E41814787-AA
Commissioning
9.4 Operating and system states
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