ABB Relion 670 Series Applications Manual page 139

1MRK 505 370-UUS Rev. K
IEC16000148 V2 EN-US
Figure 78:
Step 4: ACT engineering of the Bus Coupler bays at Section 1
The bus-coupler bay is used to interconnect the differential zones via a circuit breaker within one section.
In this particular station, the Bus-Coupler 01 is located at Section 1 and consequently it can be
connected to either Z1 or Z2 or Z3. How it is connected depends on the status of the six busbar
disconnectors (i.e. three on each side). More specifically, the following need to be done, for each bus
coupler bay:
1. Connect the two auxiliary contacts (i.e. normally open and normally closed auxiliary contacts or also
sometimes called "a & b contacts") from each of the six busbar disconnectors to the IED. This can
be done by wiring using binary inputs or via communication (e.g. via GOOSE or via LDCM).
2. Use six BDCGAPC function blocks (i.e. one per busbar disconnector) to derive open or closed
status of the respective disconnector primary contacts.
3. Connect the close status output from each BDCGAPC function block to the respective zone control
input on the bus-interconnector function block BICPTRC_xx. This will ensure proper dynamic
inclusion of the CT measurements from the two CTs located within the bus-section bay towards the
differential protection zones.
4. Connect the two currents from the TRM via pre-processing blocks to the bus-interconnector function
block BICPTRC_xx. Ensure overlapping of the two CTs. In case that only one CT is available,
connect this CT to both CT inputs on the BICPTRC_xx function block and then invert one of the two
inputs in software by using the parameter setting OperMode. This shall be done taking into account
the actual location of the CT star point in this bay.
5. Connect the trip output from BICPTRC_xx function block to the binary output contact (alternatively
the tripping can also be arranged using GOOSE communication). This will ensure proper tripping of
the bus-coupler bay for any relevant operation of the BBP including BFP tripping.
ACT configuration example for Bus-coupler 01 located at Section 1 is given in Figure 79. Any other bus
coupler bays located at Section 1 shall be engineered in the similar way. For the bus coupler bays
located at Section 2, similar steps to Step 3 shall be done, except the relevant zones are then Z4, Z5 and
Z6.
Busbar protection REB670
Application manual
ACT configuration example for Feeder 17 in Section 2
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Section 6
Differential protection
IEC16000148-2-en-us.vsdx
133