An Arc Fault Circuit Interrupter (AFCI) circuit breaker is similar in that it monitors current to watch for a fault condition. Instead of current imbalances, the AFCI detects patterns of current that indicate an arc – one of the leading causes of home fires.  The AFCI is not supposed to trip because of “normal” arcs that occur when a switch is opened or a plug is removed.  However, a known problem exists with one model of Eaton breaker, particularly with the 20, 17, 15, and 12 meter bands.  See ARRL Helps Manufacturer to Resolve Arc Fault Circuit Interrupter RFI Problems in the November 19, 2013 ARRL News for additional details, including Eaton's contact information for problem resolution.

Click here to download a PDF version of the article "Questions and Answers about Arc Fault Circuit Interrupters" by Mike Gruber, W1MG, published in the September 2017 issue of QST.