Where grounded conductors of different systems are installed in the same raceway, cable, box, auxiliary gutter, or other type of enclosure, each grounded conductor shall be identified by system. Identification that distinguishes each system grounded conductor shall be permitted by one of the following means:
1) One system grounded conductor shall have an outer covering conforming to 200.6(A) or (B)
2) The grounded conductor(s) of other systems shall have a different outer covering of white or gray with a readily distinguishable colored stripe other than green running along the insulation.
3) Other and different means of identification as allowed by 206.6(A) or (B) that will distinguish each system grounded conductor.