ABB REB670 Series Applications Manual page 288

Section 12
Control
CircuitBreaker settings
CBReadyType : The selection depends on the type of performance available from the circuit
breaker operating gear. At setting OCO (circuit breaker ready for an Open – Close – Open
cycle), the condition is checked only at the start of the auto reclosing cycle. The signal will
disappear after tripping, but the circuit breaker will still be able to perform the C-O sequence.
For the selection CO (circuit breaker ready for a Close – Open cycle) the condition is also
checked after the set auto reclosing dead time. This selection has a value first of all at multi-
shot auto reclosing to ensure that the circuit breaker is ready for a C-O sequence at shot two
and further shots. During single-shot auto reclosing, the OCO selection can be used. A breaker
shall according to its duty cycle always have storing energy for a CO operation after the first
trip. (IEC 56 duty cycle is O – 0.3sec – CO – 3min – CO).
FollowCB : The usual setting is Follow CB = Off. The setting On can be used for delayed auto
reclosing with long delay, to cover the case when a circuit breaker is being manually closed
during the auto reclosing dead time before the auto recloser has issued its breaker close
command.
UnsucClByCBChk : The normal setting is NoCBCheck and the auto reclosing unsuccessful event
is then decided by a new trip within the reclaim time after the last reclosing shot. If one wants
to get the
respond to the circuit breaker close command, one can set
tUnsucCl for instance to 1.0 s.
set
BlockByUnsucCl : Setting of whether an unsuccessful auto reclosing attempt shall set the auto
recloser in blocked status. If used the
function after an unsuccessful auto reclosing attempt. Normal setting is
CutPulse : In circuit breakers without anti-pumping relays, the setting CutPulse = On can be
used to avoid repeated closing operation when reclosing onto a fault. A new start will then cut
the ongoing pulse.
tPulse : The circuit breaker closing command should be long enough to ensure reliable
operation of the circuit breaker. The circuit breaker closing command pulse has a duration set
tPulse setting. A typical setting may be tPulse = 200 ms. A longer pulse setting may
by the
facilitate dynamic indication at testing, for example, in debug mode of the Application
Configuration Tool (ACT) in PCM600. In circuit breakers without anti-pumping relays, the
setting
fault. A new start will then cut the ongoing pulse.
tReclaim : The reclaim time sets the time for resetting the function to its original state, after
which a line fault and tripping will be treated as an independent new case with a new auto
reclosing cycle. One may consider a nominal CB duty cycle of for instance, O – 0.3sec – CO –
3min – CO. However the 3 minute (180 s) recovery time is usually not critical as fault levels are
mostly lower than rated value and the risk of a new fault within a short time is negligible. A
typical time may be
cycle.
tSync : Maximum wait time for fulfilled synchrocheck conditions. The time window should be
coordinated with the operate time and other settings of the synchrocheck function. Attention
should also be paid to the possibility of a power swing when reclosing after a line fault. Too
short a time may prevent a potentially successful auto reclosing.
tCBClosedMin : A typical setting is 5.0 s. If the circuit breaker has not been closed for at least
this minimum time, an auto reclosing start will not be accepted.
tSuccessful : If the circuit breaker closing command is given and the circuit breaker is closed
within the set time interval
tSuccessful .
282
UNSUCCL (Reclosing is unsuccessful) signal in the case the circuit breaker does not
CutPulse = On can be used to avoid repeated closing operations when reclosing onto a
tReclaim = 60 or 180 s dependent on the fault level and circuit breaker duty
tUnsucCl , the SUCCL output is activated after the set time interval
UnsucClByCBCheck = CB Check and
BLKOFF input must be configured to unblock the
1MRK 505 370-UEN D
Off .
Busbar protection REB670
Application manual