ACO using LBS
An ACO scheme may be configured with ASs using LBS switchgear as either the primary or secondary device.
Operation is similar to an ACO scheme with ACRs with the differences listed below.
Detection Sequence
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If an overcurrent pickup occurs on the closed device, ACO Status will change to Not Ready: primary/secondary Detection Sequence in Progress. This state is reset when the fault has been cleared and the Supply Interrupt count is zero. If the maximum number of supply interruptions is reached and a sectionalizing trip is performed, ACO Status will change to primary/secondary is in a detection lockout and will abort/wait depending on the Protection/Detection trip to lockout On self-healing option.
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If a device performs a sectionalizing trip, it will stay in that state until an operator close operation is performed. Re-starting ACO will not reset the detection sequence, which will remain as Sectionalise, with ACO Status still indicating that a detection sequence is in progress.
Upstream Recloser Lockout
A lockout on the upstream ACR is detected if the Sequence Reset Timer expires during a detection sequence. In this case, ACO Status will change to primary/secondary upstream device is in lockout and will abort/wait depending on the Protection/Detection trip to lockout On self-healing option. If this option is selected, ACO will change to Running after the voltage supply on the respective device is normalized.