Proper way to protect cables above surface-mounted electrical panel

Question

What are the Code requirements for protecting wires going into the top of a surface mounted electrical panel? Do the wires need to be in a conduit from the top of the panel into the ceiling above? If not, do the wires need to be secured to the wall behind the panel with staples or some other support? If so, at what length does securing the wires become necessary?

I installed a new surface-mounted electrical panel in my garage, and my inspector failed me for not having protected the wires going into the top of the panel. The wires exit the top of the panel and into a 6" hole in the ceiling, which is about 16" above the top of the panel. The wires are secured at the top of the cabinet, but are otherwise not secured anywhere along the path to the hole in the ceiling. All other installation details were deemed acceptable (height, access, keep-out requirements, etc.). How should I adequately protect these wires? The inspector suggested I could simply run 2x4s alongside the panel, but this seems kind of a wonky suggestion.

Not sure this is relevant, but this new panel is in a new location from the previous panel. The previous panel was converted into a subpanel, and all its existing circuits were left in place (which incidentally have their wires running out of the top of the panel as well - equally "unprotected"). Only two additional new circuits run out of the top of my new panel.

Answer 1

Surface wiring is often allowed in areas not readily subject to damage. I'm surprised it was flagged. The panel in my unfinished basement from 1993 has a fountain of cables coming out of it and it is (was) considered acceptable.

I'm no code wizard, but I'd put lumber alongside the cables, flush on the sides of the box, between the box and the ceiling. I'd overlay a small piece of plywood (using screws to keep it removable) and call it done.

--------------------------- < -- ceiling
   ||    |   |   |   ||
   ||    |   |   |   ||
   ||    |   |   |   || < -- framing lumber with cables between
   ||    |   |   |   ||
   ||    |   |   |   ||
   -------------------
   |                  |
   |                  |
   |                  | < -- electrical panel
   |                  |

Cables need to be secured as they would anywhere in a circuit: Every four feet and within 12" of the box. Since they should already be clamped at the panel entry point, you really only need to staple up near the ceiling. If there's a gap behind the cables where they enter the ceiling, install a board of suitable thickness crosswise behind the cables and staple to that.

Answer 2

Options are to enclose the panel as suggested by inspector or staple no more then 12" from panel.

If the panel is mounted to a backer board you can staple directly to that, each wire separately, or add a 1x board across top of panel secured to adjacent studs, with the wire stapled to that.