AC arc fault detection and protection

An AC arc fault device and methodology includes acquiring a signal in response to an AC current and defining overcurrent regions that correspond to the alternating directions of the AC current and a normal region. A software module identifies a parallel AC arc event over a selected time period in response to multiple occurrences of the acquired signal moving into one of the overcurrent regions. The software module also determines average current values over multiple selected time periods and identifies a series AC arc event in response to the difference between the average values exceeding a pre-determined threshold.