On Oct 11, 7:44 am, wrote:
On Thu, 11 Oct 2007 09:40:59 -0000, Gerald Newton

wrote:
What is needed is a new label for cord and plug connected electrical
equipment used in dwelling units: "Evaluated for connection to an AFCI
protected circuit."
Perhaps this can be put in the NEC some place.

Since the main reason something trips an AFCI is a ground fault I
think this is adequately handled with the leakage standards in the
listing requirement.
I am not sure how you could certify against a false "arc fault" trip
since this is a proprietary technology and the various companies don't
use the same algorithm. This is most apparent when you look at the
spotty performance of "testers".
It is this type of varying standard that gives the AFCI the reputation
of being more voodoo and snake oil than science. The intent is great,
the implimentation is suspect. In the current state of the technology
I believe you would get virtually the same protection from a GFCI.

I think the afci is a device that can help prevent fires. However, it
is an application of high tech to an industry that has a history of
not willing to pay the price for the strick quality controls that high
tech requires. For instance, the AFCI was designed to differentiate
between bad arcs and good arcs such as created by a common light
switch. But doesn't this assume that the light switch is built within
some design parameters. What if the contacts' material are changed
from one metal to another, or what if an electronic switch is
introduced. It seems to me that the creators of the AFCI circuitry
have got an ongoing tripping crisis on their hands. I did my original
research by going to the Zlan site. Evidently these are the people
that originally invented the AFCI microprocessor. The waveforms are
very interesting at: http://www.zlan.com/waveforms.htm

ref: http://www.zlan.com/