About This Metric
These metrics evolved from the original ALR4-1 metric for correct protection system operations and now illustrate a normalized count on a per element basis of AC transmission element outages. Shown here are the metric ALR6-13 for outages that were initiated by Failed AC Substation Equipment and the metric ALR6-14 for outages that were initiated by Failed AC Circuit Equipment. The ALR6-13 metric covers automatic outages caused by the failure of AC substation equipment that are inside the substation perimeter including transformers and circuit breakers but excluding protection system equipment. The ALR6-14 metric covers automatic outages related to the failure of AC circuit equipment such as overhead or underground equipment outside the substation perimeter. These metrics are all related to the non-weather related initiating cause codes for automatic outages of AC circuits and transformers operated 200 kV and above.