Technical data
Fundamentals
2.8 Network environment of a PCS 7 plant
Time synchronization (V7.1)
Function Manual, 03/2009, A5E01216578-01
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2.8.6 Network environment on separate networks with one central plant clock
Central plant clock
If you need to synchronize more than four networks using a single central plant clock (e.g.
SICLOCK TC 400) as the time source, you can use suitable switches to provide the time
within the individual networks. The switch is only used to distribute time message frames.
The remaining plant structure is identical to the relevant plant configuration.
Structure
The following figure illustrates the recommended configuration for a PCS 7 plant on separate
networks using a single SICLOCK as the central plant clock:
6,&/2&.
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6&$/$1&(
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26VHUYHU 26VHUYHU
3ODQW
3ODQW
3ODQW
3ODQW
Time synchronization on separate networks with one central plant clock
Note
You must ensure that each network only contains one time master for providing the time.
Separate message frame traffic between the networks.
Only use the switch to transfer the time signals from the central plant clock to the relevant
network.
The function for separating message frame traffic is dependent on the components used for
connecting the networks.
● Use of suitable SCALANCE switches (e.g. SCALANCE X414-3E)
Function: Access control
● Use of an OSM/ESM
Function: Port lock
Bidirectional communication is disabled if the corresponding function is activated.