Balancing Contingency Event

Any single event described in Subsections (A), (B), or (C) below, or any series of such otherwise single events, with each separated from the next by one minute or less.
A. Sudden loss of generation:

a. Due to

i. unit tripping, or
ii. loss of generator Facility resulting in isolation of the
generator from the Bulk Electric System or from the responsible entity’s System, or iii. sudden unplanned outage of transmission Facility;

b. And, that causes an unexpected change to the responsible entity’s ACE;

B. Sudden loss of an Import, due to forced outage of transmission equipment that causes an unexpected imbalance between generation and Demand on the Interconnection.

C. Sudden restoration of a Demand that was used as a resource that causes an unexpected change to the responsible entity’s ACE.