Siemens SIMATIC ET 200AL System Manual page 1097

"Diagnostics":
"Diagnostics" provides an overview for the redundant system about the:
● System state
● Pairing state
● Operating states of the CPU
● Status of which CPU is the primary CPU and which CPU is the backup CPU
Figure 7-2 Online and Diagnostics view: Diagnostics status of the S7-1500R/H system
Diagnostics
Function Manual, 11/2019, A5E03735838-AF
Diagnostics of the S7-1500R/H redundant system
7.1 Online and Diagnostics view
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