ABB Relion Technical Manual page 366

Section 12
Control
LINE1_OP
LINE1_CL
BUS1_OP
BUS1_CL
LINE2_OP
LINE2_CL
BUS2_OP
BUS2_CL
VB1OK
VB1FF
VB2OK
VB2FF
VL1OK
VL1FF
VL2OK
VL2FF
BLOCK
ANSI05000781 V2 EN
Figure 168: Simplified logic diagram for the voltage selection function for the tie circuit breaker in breaker-and-a-
half arrangement.
360
AND
AND
AND
AND
AND
AND
OR
OR
OR
OR
NOT
AND
line1Voltage
bus1Voltage
NOT
AND
line2Voltage
bus2Voltage
AND
OR
AND
AND
AND
1MRK 502 048-UUS A
L1SEL
B1SEL
busVoltage
L2SEL
B2SEL
invalidSelection
OR
lineVoltage
selectedFuseOK
AND
VSELFAIL
AND
en05000781_2_ansi.vsd
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