ABB REB670 Series Applications Manual page 299

1MRK 505 370-UEN D
of the switching devices are uncertain. The interlocking function uses this information for
evaluation, which means that also the interlocking conditions are uncertain.
To ensure that the interlocking information is correct at the time of operation, a unique
reservation method is available in the IEDs. With this reservation method, the bay that wants
the reservation sends a reservation request to other bays and then waits for a reservation
granted signal from the other bays. Actual position indications from these bays are then
transferred over the station bus for evaluation in the IED. After the evaluation the operation
can be executed with high security.
This functionality is realized over the station bus by means of the function blocks QCRSV and
RESIN. The application principle is shown in Figure 143.
The function block QCRSV handles the reservation. It sends out either the reservation request
to other bays or the acknowledgement if the bay has received a request from another bay.
The other function block RESIN receives the reservation information from other bays. The
number of instances is the same as the number of involved bays (up to 60 instances are
available). The received signals are either the request for reservation from another bay or the
acknowledgment from each bay respectively, which have received a request from this bay. Also
the information of valid transmission over the station bus must be received.
IED
. . .
IEC05000117 V2 EN-US
Figure 143: Application principles for reservation over the station bus
The reservation can also be realized with external wiring according to the application example
in Figure 144. This solution is realized with external auxiliary relays and extra binary inputs and
outputs in each IED, but without use of function blocks QCRSV and RESIN.
Busbar protection REB670
Application manual
IED
RES_GRT
3
RESIN
EXCH_IN
EXCH_OUT
From other
. . .
SCSWI in
RESIN
EXCH_IN
EXCH_OUT
3
Station bus
SCSWI
RES_RQ
QCRSV
RES_RQ1
. .
RES_RQ8
the bay
RES_GRT1
. .
RES_GRT8
RES_DATA
2
Section 12
Control
To other
SCSWI
in the
bay
en05000117.vsd
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