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It can also be used if an Autoreclose cycle is likely to fail for conditions associated with the protected circuit, such
as during the Dead Time, if a circuit breaker indicates that it is not healthy to switch.
3.1.4 RESET LOCKOUT INPUT
If a condition that forced a lockout has been removed, the lockout can be reset by energising a logic input
appropriately mapped in the PSL. Energising the input will also reset any Autoreclose alarms.
3.1.5 POLE DISCREPANCY INPUT
Circuit breakers with independent mechanisms for each pole (phase), normally incorporate a mechanism to cater
for cases where the phases are not together. This automatically trips all three phases if they are either not all open,
or not all closed.
During single-phase Autoreclosing a pole discrepancy condition is necessarily introduced, but the pole discrepancy
device should not operate for this condition. This can be achieved using a delayed action pole discrepancy device
with a delay longer than the single-pole Autoreclose Dead Time (SP AR Dead Time setting).
Alternatively, an input can be used for external devices to indicate a pole discrepancy condition. The pole
discrepancy input is activated by an external device to indicate that all three poles of a circuit breaker are not in
the same position. If mapped in the PSL, energising the input forces three-phase tripping (providing there is not a
single-phase Autoreclose in progress). Otherwise, a signal indicating single-phase Autoreclose in progress can be
used to inhibit the external pole discrepancy device.
3.1.6 EXTERNAL TRIP INDICATION
Protection operation from a different device can be used to initiate the Autoreclose function. By default these
external trip inputs are mapped to initiate Autoreclose and to initiate breaker failure protection (if the functions are
enabled). These inputs are not mapped to the trip outputs. With appropriate mapping in the PSL however, the
external device can use this product to trip connected circuit breakers.
3.2 AUTORECLOSE LOGIC INPUTS
This section provides an overview of the logic inputs, which are derived internally.
3.2.1 TRIP INITIATION SIGNALS
The phase A, phase B and phase C trip inputs are used to initiate single-phase and three-phase autoreclose. For
the Autoreclose to work, you must ensure that these Trip Input signals remain appropriately mapped in the PSL.
3.2.2 CIRCUIT BREAKER STATUS INPUTS
Circuit breaker status information must be available as logic input(s) for Autoreclose to work. You can select
whether to use CB open, CB closed, or both, as inputs. The settings are made in the CB CONTROL column of the
menu, and you need to ensure that the PSL mapping of the chosen input(s) is correct.
3.2.3 SYSTEM CHECK SIGNALS
System Check and Check Synchronization functions produce signals which are used by the Autoreclose logic
ensure that the Autoreclose function is applied only when the system is in a suitable condition.
3.3 AUTORECLOSE LOGIC OUTPUTS
Output signals are provided to provide indication of an Autoreclose in progress (ARIP). An ARIP signal is asserted
when an Autoreclose sequence starts. It remains high from initiation, either until lockout, or until successful
Autoreclose.
An Autoreclose lockout condition resets any ‘Autoreclose in progress’ and associated signals. Signals are available
to indicate that Autoreclose is in progress and that a circuit breakers has been successfully closed.
P54A/B/C/E Chapter 7 - Autoreclose
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