ABB RELION REB500 Technical Manual page 88

Section 5
Bay protection functions
t = 0 s:
~
t = signal received
~
t = CB open:
~
IEC19000436 V1 EN-US
Figure 32: Solutions to combat reversal of power direction
BIT_TBA = (ComRec + Unblock) × MeasOreach
BIT_TBE blocks TRIP_POTT (see POTT receive logic)
The critical relay A2 cannot trip, because the reverse measurement signal [MEAS_BWD] is
maintained for at least T1 (setting
t2TransBl ). The purpose of T2 is to ensure that blocking is maintained should there be
autoreclosure of the faulted circuit.
T1 allows time for the incorrect Com Rec signal to reset. Its setting is thus given by the reset
time of relay B2 and the reset time of the communication channel. The receiver signal must not
be prolonged.
Tripping takes place instantaneously, if the tripping condition TBA is still fulfilled after the
time T1.
Tripping always causes the logic to reset, after which it remains inactive for 100 ms. The
faulted circuit will therefore be immediately tripped, for example, in the case of an
unsuccessful autoreclosure attempt.
82
A1 B1
~
A2 B2
A1 B1
~
A2 B2
A1 B1
~
A2 B2
t1TransBl ) and resets at the latest after T2 (setting
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TBA_BLOCK
TBA_BLOCK
>= 1
T T
OR OR
T1
TBA_POTT
TBA_POTT
1 1
MEAS_BWD
MEAS_BWD
>= 1
OR OR
T2
100
T2 T2 100 100
TBA_BLOCK
T T
TBA_BLOCK
OR OR
TBA_POTT
1 1
>= 1
T1
TBA_POTT
MEAS_BWD
MEAS_BWD
OR OR
>= 1
T2
100
T2 T2 100 100
TBA_BLOCK
T T
OR OR
TBA_BLOCK
TBA_POTT
1 1
>= 1
T1
TBA_POTT
MEAS_BWD
MEAS_BWD
OR OR
>= 1
T2
T2 T2 100 100
100
18000031-IEC19000436-1-en.vsdx
1MRK 505 406-UEN B
&
BIT_TBE
BIT_TBE
AND AND AND
&
BIT_TBE
BIT_TBE
AND AND AND
&
BIT_TBE
AND AND AND BIT_TBE
Bay protection functions REB500
Technical manual