9328900990 Rev L BE1-951 Protection and Control 4-65
Figure 4-60. BESTlogic Function Element Screen, Reclosing (Zone Sequence Logic)
Table 4-36 summarizes the zone sequence coordination settings.
Table 4-36. Zone-Sequence Coordination Settings
Function Range/Purpose
Zone Pickup Logic
The zone sequence pickup logic defines which
logic elements should be considered zone
sequence pickups. Only OR (+) logic can be used
– no AND (∗) variables may be used.
Recloser zone-sequence coordination detects when a downstream recloser has cleared a fault and
increments the upstream 79 automatic reclose count to maintain a consistent count with the other
recloser. A fault is presumed cleared downstream when one or more protective functions pickup and
dropout with no trip occurring. If the zone pickup logic becomes TRUE and then FALSE without a trip
output operating, then the 79 automatic reclose counter should be incremented. The Max Cycle timer
resets the shot counter.
Figure 4-61 illustrates an overall logic diagram for the recloser function.
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