Siemens Plant Central Clock TC100 - Manual (Page 82)

Parameter assignment
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SICLOCK ® TC100 Operating Instructions
Daylight saving
The device makes the daylight saving change automatically at the parameterized
switching times.
Parameter /Time/Extended/Daylight Saving (0.09.07)
The setting "Change = No" suppresses the time change, and the plant is operated
with standard time.
The calendar rule for the daylight saving time change can be defined worldwide
via a parameter.
Leap seconds
You define the leap-second calendar with the parameter
/Time/Extended/Leap Seconds[20] (0.09.05).
9.3.2 Synchronization
Synchronizaion status
You can readout the various information about the current synchronization status
via the parameter /Synchronization/Synchronization Status (0.09.09).
Protected synchronization
If a discontinuity of longer than 5 seconds occurs in the external synchronization,
the protected synchronization is activated. The synchronization is disabled, and
an alarm is triggered, which is pending as long as the discontinuity in the external
synchronization continues.
The pending synchronization disable can be ignored once and the "Protected
Synchronization" alarm cleared with the parameter entry /Synchronization/Exten-
ded/Protected Synchronization/Ignore/Clear Alarm (0.09.12) = "Yes".
Note
The preset switching times are consistent with the regulations currently valid in
the European Union.
Note
This synchronizes unconditionally with the external time, and a time jump can
occur in the plant operation.
If required, disconnect the active external synchronization in advance or delete
the server address for NTP client operation from the parameter
/NTP Client/NTP Server List[4] (0.18.02).