Siemens SIMATIC S7-1500 Function Manual page 38

To establish an online connection at least one PG/PC interface must be installed that is
physically connected with a device, for example, with an Ethernet cable. The current online
status of a device is indicated by a symbol to the right of the device in the project tree.
Figure 4-8
Requirements
● STEP 7 is open.
● A project is open.
● The project view is open.
Diagnostics
Function Manual, 11/2019, A5E03735838-AF
Partial view of network view
Setting and determining system diagnostics
4.2 Options for displaying system diagnostics
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