Ground wires in a sub panel

[Darren]

This is 1 of 3 sub panels in today's house.

I know it's hard to see, but the ground wires are corroded at each screw. Is this because the feeder wires are wrong or is this something else?

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[AHI in AR]

I'm no electric system guru, but based on the lack of corrosion on the copper wires themselves, and no signs of overheating, and the presence of corrosion on the bars, (not copper) I'd suspect an airborne corrosive agent. Water-related corrosion might be an issue IF the panels were installed prior to the time that the home was in the dry.

[hausdok]

Flatulence!

OT - OF!!!

M.

[Jim Katen]

I sometimes see corrosion like that on aluminum panel parts out at the coast. But it uniformly affects all of the aluminum parts, not just the ones that serve the grounding wires.

I don't know why there's such a limited effect on this panel.

- Jim Katen, Oregon

[MTL_Inspet_Man]

a little anti oxide paste would probably have solved the problem