Because the Cutler Hammer BR combo AFCI breakers are longer than
standard breakers I decided to do a little test fitting. My original
concern was that the ground bar would be covered so there would be a
desirable installation sequence in order to avoid having to remove
the breaker from one circuit to connect the ground for another.
It looks like the ground bar actually interferes with the installation
of a combo AFCI breaker, so on a BR2020 panel with a GBK1420 in the
standard position most of the slots on one side are not suitable for
combo AFCI breakers. Given the broad requirements for AFCI breakers
this could be a problem. Possibilities seem to be to use a smaller
ground bar (maybe GBK10) or a bigger panel, but am I missing something?
I assume mounting the ground bar in a non-standard position would void
the listing. It appears that SquareD Homeline could have the same issue.