Line Quality Supervision - Siemens SWT 3000 Equipment Manual

Functional Description
2.12 Tele Protection Over Packet TPoP
For further information about Line Clock Synchronization, refer to the Equipment Manual SWT 3000.
2.12.6

Line Quality Supervision

SWT 3000 provides the ability to measure and monitor the performance metrics for Ethernet transmission line,
for example, packet loss, packet delay, and throughput. If the transmission line condition is too bad (for
example, because the packet loss rate is too high), the related alarm occurs.
More data fields are added in the command packet to measure the packet loss rate and round-trip delay at
predefined time interval (for example, 1 sec).
Idle packets are transmitted at a very short interval to monitor whether the Ethernet line connection is still
alive. If no idle packet is received after the predefined time has elapsed, SWT 3000 will trigger the connection
loss alarm and switch over to the secondary transmission path (for example, analog or digital) if available.
Table 2-23 lists all possible line quality alarms.
Table 2-23
Alarms
Packet loss rate alarm
Command delay alarm
Connection loss alarm
Ethernet line quality data are stored in a non-volatile RAM, it means that no data are lost even if SWT 3000 is
powered off. Maximum 10,000 quality data entries can be stored. The record time interval is configurable in
PowerSys.
The quality data is shown in PowerSys under SWT 3000 > Information > Ethernet Line Interface > Quality
data in the following figure.
[ScEthLine-28032014-1, 1, --_--]
Figure 2-27
84
Line Quality Alarm
Reason
Alarm occurs if measured packet loss rate is higher than the prede-
fined threshold.
Alarm occurs if measured command delay is higher than the prede-
fined threshold.
Alarm occurs if no command or idle packet is received within the
predefined time interval.
Ethernet Line Quality Data
Smart Communication, SWT 3000 Teleprotection, Equipment Manual
C53000-G6040-C605-1, Edition 03.2020