1. A method of alternating current (AC) arc event detection, comprising: (a) a controller determining a signal in response to a current that alternates between positive and negative half-cycles; (b) the controller defining a first overcurrent region that corresponds to the positive half-cycle, a second overcurrent region that corresponds to the negative half-cycle, and a normal current region; and (c) the controller defining an AC arc event over a selected time period in response to a plurality of occurrences of the signal moving from the normal region to one of the first overcurrent region or the second overcurrent region and moving from the normal region to another of the first overcurrent region or the second overcurrent region.