ABB Relion 670 Series Applications Manual page 117

1MRK 505 370-UUS Rev. K
By a parameter setting it is possible to provide self-rest or latched trip output contacts from the IED.
However it shall be noted that the latching is electrical (that is, if DC supply to the IED is lost the output
contacts will reset).
However, sometimes due to a large number of required trip output contacts (that is, single pole operated
circuit breakers and/or main and backup trip coils), a separate trip repeat relay unit is applied for the
tripping of the circuit breakers in the station. In that case the tripping arrangement can be done in
different ways.
Trip arrangement with one-phase version
When one-phase version of the IED is used it is typically required to have three IEDs (that is, one per
phase). Thus, when busbar protection in one IED operates the trip commands will be given to all bays
but internal circuit breaker failure function will be started in the same phase only. In order to secure
internal breaker failure picking-up in all three phases it is advisable to do the following. Connect a zone,
say Zone A, trip signal from one IED to the external trip input of the Zone A in the other two IEDs. Thus
all three IEDs will then issue trip in Zone A and pick-up internally circuit breaker failure protection in all
three phases.
Note that:
• similar arrangements shall be done for the other zones
• this have to be done between all three IEDs (that is, three times)
Such a scheme can be arranged in one of the following ways:
• by wiring between three IEDs
• by using GOOSE messages when IEC 61850-8-1 is used
• by using LDCM communication module.
Note that in this case the external trip signal from other two IEDs shall be arranged via pulse timer in
configuration in order to avoid locking of the trip signal between three IED. Such arrangement via
GOOSE is given in Figure 53:
Busbar protection REB670
Application manual
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Section 6
Differential protection
SEMOD130408-6 v4
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