ABB RED650 - Page 113

When the line differential protection function in local IED is set to test mode,
LDLPSCH sets the remote IEDs in a remote test mode and block the trip outputs in
the remote IEDs. Figure 40 shows a simplified block diagram which illustrates
block signal handling by LDLPSCH.
The following figures indicates up to 4 remote terminals, the 650 products can only
support two remote terminals.
ReleaseLocal
TestModeSet
1
Block signal Logic of LDLPSCH
50 ms
50 ms
50 ms
t
t
t
100 ms
t
TestModeRemoteTerm1
TestModeRemoteTerm3
TestModeRemoteTerm4
TestModeRemoteTerm2
BlockRemoteTerm1
BlockRemoteTerm2
BlockRemoteTerm3
BlockRemoteTerm4
OPEN CT BLK
TestModeInput
TERMINALOUTOFSERVICE
BLOCK
LocalDiffBlock
LOCALDIFFBLOCKED
CTFailOCTToRemote
(signal to LDCM)
TestModeToRemote
Block Remote Trip
Block Remote Trip
BlockToRemote
IEC13000259-3-en.vsd
IEC13000259 V3 EN-US
Figure 40: Block signal logic of LDLPSCH
When LDLPSCH receives the trip signal from local IED (or remote IED), this trip
signal is transferred to remote IEDs (or local IED) in the protection zone. Figure
41
shows a simplified block diagram which illustrates trip signal handling by
LDLPSCH.
1MRK 505 394-UEN A Section 6
Differential protection
Line differential protection RED650 2.2 IEC 107
Technical manual