GPSSyncErr: If GPS synchronization is lost, the synchronization of the line differential
function will continue during 16 s. based on the stability in the local IED clocks.
Thereafter the setting Block will block the line differential function or the setting Echo
will make it continue by using the Echo synchronization method. It shall be noticed
that using Echo in this situation is only safe as long as there is no risk of varying
transmission asymmetry.
CommSync: This setting decides the Master or Slave relation in the communication
system and shall not be mistaken for the synchronization of line differential current
samples. When direct fibre is used, one LDCM is set as Master and the other one as
Slave. When a modem and multiplexer is used, the IED is always set as Slave, as the
telecommunication system will provide the clock master.
OptoPower: The setting LowPower is used for fibres 0 – 1 km (0.6 mile) and
HighPower for fibres >1 km (>0.6 mile).
TransmCurr: This setting decides which of 2 possible local currents that shall be
transmitted, or if and how the sum of 2 local currents shall be transmitted, or finally if
the channel shall be used as a redundant channel.
In a breaker-and-a-half arrangement, there will be 2 local currents, and the grounding
on the CTs can be different for these. CT-SUM will transmit the sum of the 2 CT
groups. CT-DIFF1 will transmit CT group 1 minus CT group 2 and CT-DIFF2 will
transmit CT group 2 minus CT group 1.
CT-GRP1 or CT-GRP2 will transmit the respective CT group, and the setting
RedundantChannel makes the channel be used as a backup channel.
ComFailAlrmDel: Time delay of communication failure alarm. In communication
systems, route switching can sometimes cause interruptions with a duration up to 50
ms. Thus, a too short time delay setting might cause nuisance alarms in these situations.
ComFailResDel: Time delay of communication failure alarm reset.
RedChSwTime: Time delay before switchover to a redundant channel in case of
primary channel failure.
RedChRturnTime: Time delay before switchback to a the primary channel after channel
failure.
AsymDelay: The asymmetry is defined as transmission delay minus receive delay. If a
fixed asymmetry is known, the Echo synchronization method can be used if the
parameter AsymDelay is properly set. From the definition follows that the asymmetry
will always be positive in one end, and negative in the other end.
AnalogLatency: Local analog latency; A parameter which specifies the time delay
(number of samples) between actual sampling and the time the sample reaches the
Section 5 1MRK504116-UUS C
Remote communication
848
Application manual
To Next Page
Loading...
Need help?
General
