watthead, iwire,
I understand that GFCIs will operate on ungrounded circuits when a typical fault to ground occurs.
However, I believe that AFCIs are designed with a GFCI component, so that low level (less than 75 amps?) arcing faults will eventually cause a fault between the line and the grounding conductor, which if not present, will not permit a ground fault to occur inside the cable, and therefore, not open the circuit.
This, I believe, is part of the controversy surrounding the performance of AFCIs.
I'd like to hear more input, please.
[This message has been edited by Redsy (edited 09-25-2003).]
