Condensation in Subpanel
I have a very unusual issue occurring in my subpanel right now. I installed this subpanel about 2 years ago and recently noticed that one of the two metal anchors I used is rusting over. This subpanel is mounted to a basement wall and is about 1 1/2 feet above ground level. It is actually at the same level as the main box that was installed in early 2008. These two anchors look like they're made of brass or something similar. They're not aluminum or silver in appearance. I don't have any water marks anywhere or any drips. All the wiring, breakers, and bus bars look clean and dry. What's unusual is the fact that one of these anchors has rusted over but the other one still looks almost brand new with just a very very slight amount of oxidation. They are spaced about 6 inches apart. Why would one corrode and the other not corrode? Is it something to be concerned about? Also, my basement is usually somewhat damp. I never have more than a 1/2 of water in the basement. We use a de-humidifier, but I've noticed that several of my tools I keep down there have developed some rust on them over the last two years.