depend on a circuit breaker failing to clear the fault. A protection trip signal present
when the circuit breaker is reclosed will result in a new trip. The user can set a
maximum start pulse duration time tLongStartInh. This start pulse duration time is
controlled by the LongStartInhib setting. When the start pulse duration signal is
longer than set maximum start pulse duration, the auto reclosing sequence
interrupts in the same way as for a signal to the INHIBIT input.
tLongStartInh: The user can set a maximum start pulse duration time
tLongStartInh. At a set time somewhat longer than the auto reclosing dead time,
this facility will not influence the auto reclosing. A typical setting of tLongStartInh
could be close to the auto reclosing dead time.
tInhibit: To ensure reliable interruption and temporary blocking of the auto recloser
a resetting time delay tInhibit
is used. The auto recloser will be blocked this time
after the deactivation of the INHIBIT input. A typical resetting delay is 5.0 s.
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.
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 Off.
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 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
1MRK 506 375-UEN A Section 12
Control
Railway application RER670 2.2 IEC 235
Application manual
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