V00512
CB Closed 3 ph
AR In Progress
AR on Man Close
Inhibited
Pulse to start inhibit timer
Main Protection Start
SEF Protection Start
1
Auto Mode (int)
1
&
Enabled
&
& Autoreclose inhibit
Figure 158: AR Initiation inhibit
If a protection operation occurs during the inhibit period, Autoreclose is not initiated. A further option is provided
by setting Man Close on Flt. If this is set to Lockout, Autoreclose is locked out (AR Lockout) for a fault during the
inhibit period following manual CB closure. If Man Close on Flt is set to No Lockout, the CB trips without
reclosure, but Autoreclose is not locked out.
You may need to block selected fast non-discriminating protection in order to obtain fully discriminative tripping
during the AR initiation inhibit period following CB manual close. You can do this by setting Manual Close to
Block Inst Prot. A No Block setting will enable all protection elements immediately on CB closure.
If setting AR on Man Close is set to Enabled, Autoreclose can be initiated immediately on CB closure, and settings
AR Inhibit Time, Man Close on Flt and Manual Close are irrelevant.
7.9 AUTORECLOSE LOCKOUT
If protection operates during the reclaim time following the final reclose attempt, the IED is driven to lockout and
the Autoreclose f
unction is disabled until the lockout condition is reset. This produces the alarm, AR Lockout. The
Block AR input blocks Autoreclose and causes a lockout if Autoreclose is in progress.
Autoreclose lockout can also be caused by the CB failing to close due to an unhealthy circuit breaker (CB springs
not charged or low gas pressure) or if there is no synchronisation between the system voltages. These two
conditions are indicated by the alarms CB Unhealthy and AR No Sys Check This is shown in the AR Lockout logic
diagram as follows:
P14x Chapter 13 - Autoreclose
P14xEd1-TM-EN-1 301
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