Control and Logic Functions
79 Automatic Reclosing
Autoreclose sequences can be specified differently for Phase, Earth, Externally Initiated and GS Sensitive Earth
faults. Sequences should be simulated for each applicable different fault type with the actual relay settings
required for service installed in the relay.
The relay requires that the correct indications are received at the CB auxiliary contact inputs and that the
injected current and voltage used to generate protection operations are timed to the autoreclose sequence to
provide a realistic simulation of the actual system conditions.
The Instruments menu contains Autoreclose Meters for the Autoreclose State and the Shot No.
which are useful during sequence testing.
When autoreclose is in service and waiting for a trip to initiate a sequence the instrument should display In
Service. When a trip occurs the instrument should display Sequence in Progress. If it does not it indi-
cates that the protection trip is not configured to start autoreclose.
When the CB is Open, the protection trip is reset and the voltage conditions are correct the instrument should
indicate that the First Deadtime is in progress. If the instrument continues to display Sequence in
Progress and then switches to Lockout when the Sequence Fail Timer expires, this indicates that
those conditions have not been met.
At the end of the expected deatime, the instrument will display Close Inhibit until voltage conditions are
met. This may be instantaneous depending on settings and applied signals or may time out to Lockout is
conditions are not met. In this case the voltages, connections and settings likely require investigation.
The instrument should then display Close Pulse and then Reclaim. Lockout or failure usually indicates a
circuit‑breaker problem or close onto fault resulting in termination of the sequence for the applied settings.
If a further trip does occur during the Close Pulse or Reclaim time then the instrument will return to
Sequence in Progress and proceed with the next shot.
The time stamped Events listing can be downloaded from the relay to a pc to allow diagnosis of the
sequence including measurements of sequence Dead Times and other timing without the use of external
measuring equipment or complex connections.
Quick Logic
If this functionality is used, the logic equations may interfere with testing of other protection functions in the
relay. The function of the Quick Logic equations should be tested conjunctively with connected plant or by
simulation to assess suitability and check for correct operation on an individual basis with tests specifically
devised to suit the particular application.
9.11
9.11.1
9.11.2
Functional Tests
9.11 Control and Logic Functions
500 Reyrolle 7SR5, Overcurrent Protection Device, Device Manual
C53000-G7040-C014-1, Edition 11.2019
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