Autoreclose cycles can be initiated by:
● Pr
otection functions internal to the product
● A Trip Test feature
● External protection equipment
● Evolving fault combinations
Internal Protection Functions
Many of the protection functions in the product can be programmed to initiate or block Autoreclose. The
associated settings are found in the Autoreclose column and the available options are No Action, Initiate
AR, or Block AR. If set to Block AR operation of the protection function blocks the Autoreclose function and
forces a lockout.
Trip Test Feature
The Test Autoreclose command cell in the COMMISSION TESTS column can be used to initiate an Autoreclose
cycle. Each option provides a 100 ms pulse output. There is also a ‘No Operation’ option to exit the command field
without initiating a test.
External Protection Equipment
Protection operation from a different device can be used to initiate Autoreclose via PSL. By default these external
trip input signals are mapped to initiate Autoreclose. 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.
Evolving Fault Combinations
The Autoreclose function would normally be initiated by a single condition (such as a single-phase fault). If,
however, the system conditions evolve such that other conditions that could initiate Autoreclose, then the
dynamics of the Autoreclose logic need to adapt. For example, if a single-phase fault evolves into a multi-phase
fault, then the operation of the Autorecloser must consequently adapt. To achieve this signals are generated to
indicate conditions such as evolving faults, re-operation of protection, combinations of initiation by internal
protection, external protection, or test features, which control the Autoreclose sequencing.
Records of initiating conditions are stored and used to control the sequencing. Initiation can be from a protection
function integrated in the product, from external protection and internal sources such as the Autoreclose test
function. Initiation can be further qualified by the phases causing the initiation. These conditions are stored in
signals that generally feature “MEM”- memory, or “AR” – Autoreclose, in the signal name.
P54A/B/C/E Chapter 7 - Autoreclose
P54xMED-TM-EN-1 153
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