ABB Relion 670 Series Applications Manual page 203

1MRK 505 370-UUS Rev. K
tCBAlarm: Time delay for alarm in case of indication of faulty circuit breaker. There is a binary input
52FAIL from the circuit breaker. This signal is activated when internal supervision in the circuit breaker
detect that the circuit breaker is unable to clear fault. This could be the case when gas pressure is low in
a SF6 circuit breaker. After the set time an alarm is given, so that action can be done to repair the circuit
breaker. The time delay for backup trip is bypassed when the 52FAIL is active. Typical setting is 2.0
seconds.
tPulse: Trip pulse duration. This setting must be larger than the critical impulse time of circuit breakers to
be tripped from the breaker failure protection. Typical setting is 200 ms.
tStartTimeout: When one of the two "Follow Modes" is used, there is a settable timer tStartTimeout which
will block the external BFI_3P input signal when it times-out. This will automatically also reset the t1 and
t2 timers and consequently prevent any backup trip command. At the same time the STALARM output
from the function will have logical value one. To reset that condition external BFI_3P signal shall be
removed. This is done in order to prevent unwanted operation of the breaker failure function for cases
where a permanent BFI_3P signal is given by mistake (e.g.due to a fault in the station battery system).
Note that any backup trip command will inhibit running of tStartTimeout timer.
Table 35: Setting summary for FunctionMode, StartMode and RetripMode
No. StartMode
FunctionMode = Current
1 LatchedStart
2 LatchedStart
3 LatchedStart
4 FollowStart
5 FollowStart
6 FollowStart
Table continues on next page
Busbar protection REB670
Application manual
RetripMode t1 and t2 initiated
with
Off external START
UseFunctionMode external START
Always external START
Off external START
UseFunctionMode external START
Always external START
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When t1 has When t2 has elapsed,
elapsed, TRRET TRBU will be given if
will
never be given current is above set
level of IPh>
be given if current current is above set
is above set level level of IPh>
of IPh>
always be given current is above set
level of IPh>
never be given current is above set
level of IPh>
be given if current current is above set
is above set level level of IPh>
of IPh>
be given if external current is above set
START is present level of IPh>
Section 7
Current protection
GUID-B5D9E7FE-5805-47A8-B290-08E0EE76D5EB v1
t1 and t2 will be
stopped (reset) if
t1 and (t2 or t2MPh)
and 150ms expires
and current is below
set level of IPh>
t1 and (t2 or t2MPh)
and 150ms expires
and current is below
set level of IPh>
t1 and (t2 or t2MPh)
and 150ms expires
and current is below
set level of IPh>
external START
disappears
external START
disappears
external START
disappears
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