Understood Potseal
Fwiw, just
what an arc is ,
how it's created ,and what the
effects may be has been constitutes the heart of the issue.
One of the UL papers CMP-2 points out in their '14 substantiations is
Effectiveness of Circuit Breakers in Mitigating Parallel Arcing Faults in the Home Run Published literature from the early 1990s demonstrated the issue with high magnetic trip breakers failing
to mitigate arcing faults: for example, as cited by Franklin.
Franklin’s work showed that 15A breakers
manufactured in North America at the time exhibited widely varying magnetic trip levels, as low as 120A
and potentially exceeding 800A. He contrasted this to European 15A breakers, which magnetically tripped
at 100A, allowing far less arc energy to dissipate.
Franklin claims that experimental work with arcing faults
shows that arcing currents are “almost always” in the range of 150A to 400A. He further states that an
arcing current below 100A has “never” been observed.
You'll find the av mag trips for afci's in the 75A range ....
~S~
