related multiple-outage occurrence caused by a single event but conditional on the prior occurrence of another event
NOTE 1 – For example, when the single event is a line failure and the prior occurrence is a failure of a protection device of the primary protection zone, the multiple-outage occurrence is the outage of the faulty line and the adjacent circuit(s) taken out of service by the back up protection equipment.
NOTE 2 – See figure 191-25.
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