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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2.8.5 Network environment in redundant, high-availability networks
Introduction
Always install redundant networks in a PCS 7 plant as a precaution against production
losses caused by failures in the network connections. This will ensure that communication
via the redundant network will remain intact if an area of the terminal bus fails. The domain
controllers synchronize one another's time on the basis of Windows mechanisms.
Central plant clock
The SICLOCK TC 400 is suitable for operation as a central plant clock. The SICLOCK can
distribute the time signal directly to the plant networks.
Structure
The figure below illustrates the recommended configuration for a PCS 7 plant with a
redundant network structure (redundant terminal bus and plant bus):
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