Greg - Wire has to be protected at it's ampacity 240.4 and if their is an adjusted ampacity the overcurrent must match that new ampacity and sometimes you can round up
I think a more accurate statement than that would be "conductors aren't allowed to melt", citing section 310.10.
Citing 240.4 as an all-encomposing provision is little bit untrue, when you consider the applications of 240.4(A), (E) and (G)
