Technical data

Time synchronization (V7.1)
Function Manual, 03/2009, A5E01216578-01
45
Planning time synchronization
4
4.1 Selecting the time master
Selecting the time master
On a time-synchronous PCS 7 plant, you require a time master to which the additional plant
components can be synchronized. The table below lists the components that are used as
time masters, depending on the network environment:
Time master With time
source ...
Provides the
time via ...
Time master
forwards the time to...
Forwards the time to ...
Terminal bus Domain controller -
Terminal bus OS server Terminal bus with OS servers and
OS clients
SICLOCK Central clock:
Not
synchronized,
or
synchronized
(e.g. via GPS
or DCF 77)
Plant bus Automation systems -
Terminal bus OS clients OS server
- BIOS clock
- GPS
- DCF 77
Plant bus CP of the OS servers that are
active time masters
Automation systems
OS clients Domain controllers - GPS
- DCF 77
- NTP server
Terminal bus OS server
Plant bus, including the automation
systems
PC
- BIOS clock
- GPS
- DCF 77
- NTP
All OS servers as
time masters