TerminalNo is used to assign a unique address to each LDCM in all current
differential IEDs. Up to 256 LDCMs can be assigned a unique number. For
example, in a local IED with two LDCMs:
• LDCM for slot 305: set TerminalNo to 1 and RemoteTermNo to 2
• LDCM for slot 306: set TerminalNo to 3 and RemoteTermNo to 4
A unique address is necessary to give high security against
incorrect addressing in the communication system. If the same
number is used for TerminalNo in some of the LDCMs, a loop-back
test in the communication system can give an incorrect trip.
RemoteTermNo is used to assign a number to each related LDCM in the remote
IED. For each LDCM, RemoteTermNo is set to a different value than TerminalNo,
but equal to the TerminalNo of the remote end LDCM. In the remote IED,
TerminalNo and RemoteTermNo are reversed as follows:
• LDCM for slot 305: set TerminalNo to 2 and RemoteTermNo to 1
• LDCM for slot 306: set TerminalNo to 4 and RemoteTermNo to 3
The redundant channel is always configured to the lower position,
for example:
• Slot 305: main channel
• Slot 306: redundant channel
The same is applicable for slot 312-313.
DiffSync: defines the method of time synchronization for the line differential
function: Echo
Using Echo in this case is safe only if there is no risk of varying
transmission asymmetry.
CommSync defines the Master and Slave relation in the communication system,
and should not be mistaken for the synchronization of line differential current
samples. When direct fiber is used, one LDCM is set as Master and the other as
Slave. When a modem and multiplexer is used, the IED is always set as Slave
because the telecommunication system provides the clock master.
OptoPower has two settings: LowPower is used for fibres 0 – 1 km and HighPower
for fibres >1 km.
Section 19 1MRK 505 393-UEN B
Remote communication
396 Line differential protection RED650 2.2 IEC
Application manual
To Next Page
Loading...
Need help?
General
