10.2.6.2 Control of the auto-reclosing open time
There are settings for three-phase auto-reclosing open time, t1 3Ph to t5 3Ph.
10.2.6.3 Long trip signal
In normal circumstances the trip command resets quickly due to fault clearing. The
user can set a maximum trip pulse duration tTrip. A long trip signal interrupts the
reclosing sequence in the same way as a signal to input INHIBIT.
Reclosing checks and the reclaim timer
When dead time has elapsed during the auto-reclosing procedure certain conditions
must be fulfilled before the CB closing command is issued. To achieve this, signals are
exchanged between program modules to check that these conditions are met. In three-
phase reclosing a synchronizing and/or energizing check can be used. It is possible to
use a synchro-check function in the same physical device or an external one. The
release signal is configured by connecting to the auto-reclosing function input SYNC.
If reclosing without checking is preferred the SYNC input can be set to TRUE (set
high). Another possibility is to set the output of the synchro-check function to a
permanently activated state. At confirmation from the synchro-check, the signal
passes on.
By choosing CBReadyType = CO (CB ready for a Close-Open sequence) the
readiness of the circuit breaker is also checked before issuing the CB closing
command. If the CB has a readiness contact of type CBReadyType = OCO (CB ready
for an Open-Close-Open sequence) this condition may not be complied with after the
tripping and at the moment of reclosure. The Open-Close-Open condition was
however checked at the start of the reclosing cycle and it is then likely that the CB is
prepared for a Close-Open sequence.
The synchro-check or energizing check must be fulfilled within a set time interval,
tSync. If it is not, or if other conditions are not met, the reclosing is interrupted and
blocked.
The reclaim timer defines a time from the issue of the reclosing command, after which
the reclosing function resets. Should a new trip occur during this time, it is treated as
a continuation of the first fault. The reclaim timer is started when the CB closing
command is given.
A number of outputs for Autoreclosing state control keeps track of the actual state in
the reclosing sequence.
1MRK 511 287-UEN A Section 10
Control
231
Technical manual
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