I know what you are talking about. If the little sliver was supposed to be okay then the entire wire would be okay if it were bare.
Is the sliver a strand of wire that missed a crimp connector?
Since with vibration of position it could touch the metal enclosure, it is distinctly unintentional.
Obviously there is something serviceable in there. Perhaps the fuse was installed locally?
NOTICE
Control box cover must be reinstalled after servicing to insure proper...?
