Control Of The Auto-Reclosing Open Time - ABB REC650 ANSI Technical Manual

1MRK 511 287-UUS A
10.2.6.2
10.2.6.3
Technical manual

Control of the auto-reclosing open time

There are settings for three-phase auto-reclosing open time, t1 3Ph to t5 3Ph.
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 reset 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
synchronism 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 synchronism check function to a permanently
activated state. At confirmation from the synchronism 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 synchronism 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 reset 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 reset 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.
Section 10
Control
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