Siemens SIMATIC PCS 7 Function Manual page 100

Configuring time synchronization
5.8 Configuring time synchronization on an AS
4. Select the PN-IO interface, followed by Edit > Object properties.
5. Switch to the "Time-of-Day Synchronization" tab.
6. Activate the "Enable Time-of-Day Synchronization in NTP Mode" check box in the "NTP
7. Enter the IP address of the central plant clock (SICLOCK TC 400 or SICLOCK TM) as the
8. Enter the value "10" in the "Update Interval (Seconds)" field.
9. Click "OK".
Result
The automation system uses NTP mode for time synchronization.
Additional information
A list of CPU types that have an integrated Ethernet interface is provided in the documentation
PCS 7 Process Control System; Released Modules .
100
The "Properties PN-IO" dialog box opens.
Mode" group.
NTP server address.
Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02