ABB REF 610 Technical Reference Manual page 33

1MRS 755535
Feeder Protection Relay
Technical Reference Manual - ANSI Version
When reclosing is disabled, or the circuit breaker does not close before expiration of
the set CB closing time, the circuit breaker will remain open and the AR function
will generate a CB Reclosing Failed signal.
Reclosing is disabled and the CB Reclosing Failed signal generated also if
an AR initiation signal is active, i.e. the fault has not been cleared, when reclosing
begins.
The duration of the reclosing command is settable (CB closing time). However,
reclosing of the circuit breaker will end immediately after the AR function has
received information that the circuit breaker has been closed, or if a protection trips
the circuit breaker again.
Blocking of protection elements
In several applications, such as fuse-saving (refer to section Fast tripping and
initiation of shot 1 using two protection elements), the aim is at fast tripping and
initiation of shot 1 and delayed tripping and initiation of shot 2 and 3. Consequently,
if two protection elements are used, one fast and the other one delayed, the fast
element should be set to be blocked by the AR function during shot 2 and 3.
The protection elements can be set to be blocked at shot 1 and/or shot 2 and 3. The
selection is made in SG2 (see table 4.1.4.10-11).
Definite trip alarm
The AR function will generate a definite trip alarm signal after an unsuccessful
auto-reclose sequence, i.e. when no more auto-reclose shots are allowed but the
network fault has not be cleared, the circuit breaker is open and there is no ongoing
shot. The definite trip alarm signal will also be generated in case a protection trips
the circuit breaker while the AR function is disabled.
Note!
The definite trip alarm signal is active for 1 second.
Note!
The definite trip alarm signal will not be generated if the AR function has been set
out of operation.
Lockout of the auto-reclose function
The lockout signal indicates whether the AR function is ready for shot initiation. The
AR function will be locked out in any of the following situations:
• the AR function generates a definite trip alarm
• the AR function is disabled
• circuit-breaker closing fails
• manual circuit-breaker closing is detected
The lockout signal will be reset and the AR function ready for shot initiation on
expiration of the set reset time. The set reset time will pickup when the definite trip
alarm signal, the AR disable signal or the CB reclosing failed signal has
been reset or the circuit breaker closed, depending on the reason for the AR function
being locked.
REF 610
33