So how exactly does the built-in test button on an AFCI breaker work? Since it cannot create an arc fault, one would have to ASSume that it simply tests the trip mechanism "downstream" of the software "black box" that supposedly does the waveform analysis and arc detection. In other words, it CANNOT check the actual operation of the complete device, unlike the test feature on a GFCI, which actually creates a differential current between hot and neutral. Has anyone taken one of these things apart to see what is actually going on inside? I have only seen the block diagrams and descriptions from manufacurer websites and such. I haven't come across a defective unit to dissect, and they are too expensive to sacrifice a "working" one.
If the built-in test function doesn't do a thorough test, and neither can an external tester, I guess that the public has to take the functionality of these things "on faith"? Smells like the makings of a lawsuit down the road, when a fire starts on an AFCI "protected" circuit....
