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801299.00
7200 sec / 15 = 480 s/step (
8 min/step
)
Stratum increase is stopped at configured Stratum limit.
E.g. the Stratum timeout is 2 hours (increasing of the Stratum every 8 minutes), the
Stratum limit is set to 12. These means after 8 minutes of synchronisation loss the
device will increase the Stratum from 1 to 2. 8 minutes later the device will change the
Stratum from 2 to 3 and so on. After 11 steps * 8 minutes = 88 minutes the Stratum of
the device is 12. From now on the device will have the Stratum 12 until it is
synchronized again. The Stratum increase stops, because the device has from now on
the synch alarm (as configured).
Technical description of the stratum functionality:
Stratum_Fix > 0
Stratum =
Stratum_Fix
Synchronisation
= ok
Stratum = 1
Stratum = (current time – last synch time) / (stratum timeout * 15);
(Max stratum value = St_max)
Yes
Yes
No
No
Legend:
Stratum timeout:
Stratum TO <0-16>, Stratum error timeout time 1-999 [h], for loss
of the source
St_fix:
0..15, configurable fix stratum, 0 = auto
Max Stratum value: 1..16, configurable stratum limit
current time [s]:
current time (can be found in the overview => time state)
last synch time [s]: time of the last synchronization (can be found in the overview =>
time state)
8.5
Source change example situation
For better understanding of how source changes happen, consider the following
situation:
-
DTS has 3 sources configured: 1. SyncE, 2. PTP, 3. Freq.
-
Time source change mode is set to manual.
-
DTS is powered off, all sources are correctly configured and cables plugged-in.
Now, the DTS is powered on and system starts up. Initial synchronization is done by
using PTP time even though it does not have priority 1, but because it’s the fastest
source available.
10 Minutes after choosing PTP as active source, DTS will change to SyncE, it’s priority
1 source.
Further, consider the following scenario:
