Siemens SIMATIC PCS 7 Function Manual page 41

Rules
In order to avoid time jumps, please observe the following rules when setting up the hierarchy
for the PCS 7 plants within a Windows domain that contains multiple hierarchies:
● All identical structures must be assigned to the same levels in a Windows domain that
● Create only one hierarchy level under the root domain. Set up any additional Windows
Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02
contains multiple hierarchy levels. This will prevent unwanted time differences.
For further information, refer to the section titled "Time levels for a PCS 7 plant (stratum)
(Page 17)".
domains you may require on the same hierarchy level as the existing subdomains.
Configurations for time synchronization of a PCS 7 plant
3.4 Configuration for time synchronization in a Windows domain
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