Siemens SIMATIC ET 200AL System Manual page 1650

Error and alarm texts
You can show diagnostics buffer entries and alarm messages for the relevant automation
system on the display.
To show the diagnostics buffer entries of the CPU, navigate on the display via the menu items
"Diagnostics" > "Diagnostics buffer".
Figure 4-6
To show the alarm messages of the automation system, navigate through the menu items
"Diagnostics" > "Alarms" > "Alarm text" on the display.
Note
Updating the alarm display
The display shows the currently read status of the CPU in static form, the display is not
automatically updated. The alarm display is updated after it has been exited and opened
again.
You set the automatic updating of the diagnostics information under: "Display" >
"DiagnosticRefresh".
PROFINET with STEP 7
Function Manual, 05/2021, A5E03444486-AL
Display of diagnostics buffer
Diagnostics and maintenance
4.3 Diagnostics via the display of the S7-1500 CPUs
85