Dirty or burned?

[Rick Maday]

What do you think?

[Jeffrey R. Pope]

Neither.

Normal discoloration, that occurred during the manufacturing process. . .

[Rick Maday]

Originally Posted by jpope

Neither.

Normal discoloration, that occurred during the manufacturing process. . .

Thanks.

Main breaker mysteriously shut off during the inspection.
There was one light on in the whole place until it shut down.

[Paul Dickerson]

I would not look twice at the discoloration on the bus bar. But I would be very concerned about a mysteriously popping main breaker. Defer it to a licensed electrician. Don't try to re-set it.