ABB Relion 670 series, Technical Reference Manual

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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 12
1MRK505222-UUS C
Control
638
Technical reference manual