recloser increases its actual shot number by one and enters “reset time” status. If a start is
received during this reclaim time the auto recloser is proceeding as usual but with the dead
time for the increased shot number. Every new increase of the shot number needs a new
activation of the ZONESTEP input. The setting NoOfShots limits of course the possibility
to increase the shot number. This functionality is controlled by the setting ZoneSeqCoord.
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 UNSUCCL (Reclosing is unsuccessful) signal in the
case the circuit breaker does not respond to the circuit breaker close command, one can set
UnsucClByCBCheck = CB Check and set tUnsucCl for instance to 1.0 s.
BlockByUnsucCl: Setting of whether an unsuccessful auto reclosing attempt shall set the
auto recloser in blocked status. If used the BLKOFF input must be configured to unblock
the function after an unsuccessful auto reclosing attempt. Normal setting is Disabled.
CutPulse: In circuit breakers without anti-pumping relays, the setting CutPulse = Enabled
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 by the tPulse setting. A typical setting may be tPulse = 200 ms. A longer pulse setting
may 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 CutPulse = Enabled can be used to avoid repeated closing
operations when reclosing onto a fault. A new start will then cut the ongoing pulse.
1MRK 506 369-UUS - Section 15
Control
Line distance protection REL670 2.2 ANSI 677
Application manual
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