ABB Relion 650 Series Technical Manual page 150

Section 8
Control
B1QOPEN
B1QCLD
B2QOPEN
B2QCLD
UB1OK
UB1FF
UB2OK
UB2FF
ULN1OK
ULN1FF
BLOCK
IEC05000779 V2 EN-US
Figure 59: Logic diagram for the voltage selection function of a single circuit breaker with double busbars
144
bus 1 voltage is used. All other combinations use the bus 2 voltage. The outputs
B1SEL and B2SEL respectively indicate the selected Bus voltage.
The function checks the fuse-failure signals for bus 1, bus 2 and line voltage
transformers. Inputs UB1OK-UB1FF supervise the MCB for Bus 1 and UB2OK-
UB2FF supervises the MCB for Bus 2. ULN1OK and ULN1FF supervises the
MCB for the Line voltage transformer. The inputs fail (FF) or healthy (OK) can
alternatively be used dependent on the available signal. If a VT failure is detected
in the selected voltage source an output signal USELFAIL is set. This output signal
is true if the selected bus or line voltages have a VT failure. This output as well as
the function can be blocked with the input signal BLOCK. The function logic
diagram is shown in figure 59.
AND
AND
bus1Voltage
bus2Voltage
OR
OR
OR
Voltage selection for a 1 1/2 circuit breaker arrangement
Note that with 1½ breaker schemes three Synchrocheck functions must be used for
the complete diameter. Below, the scheme for one Bus breaker and the Tie breaker
is described.
1
AND
OR
AND
1MRK 511 424-UEN B
B1SEL
B2SEL
invalidSelection
AND
busVoltage
selectedFuseOK
AND
USELFAIL
AND
en05000779-2.vsd
Bay control REC650 2.2 IEC
Technical manual
M14839-3 v8