Patent ID: 7633729

Claim:
A method of detecting and indicating a presence of alternating current (AC) series arc fault events in current supplied by an AC electrical power source to an electrical load for the power source, comprising the steps of: measuring positive and negative current through the load over a first sample cycle of the AC power to establish first measured positive and first measured negative current levels; determining the absolute value of the first measured positive and first measured negative current levels to establish a first absolute positive current level and a first absolute negative current level; adding the first absolute positive current level and the first absolute negative current level to establish a first sum current level; measuring positive and negative current through the load over a second sample cycle of the AC power staggered from the first sample cycle to establish second measured positive and second measured negative current levels; determining the absolute value of the second measured positive and second measured negative current levels to establish a second absolute positive current level and a second absolute negative current level; adding the second absolute positive current level and the second absolute negative current level to establish a second sum current level; subtracting the second sum current level from the first sum current level to establish a current difference level; and indicating a series arc fault event if the current difference level exceeds a predetermined threshold level.