Wow. I am amazed this house didn’t burn down. I never noticed this before. But the sub panel in my basement, the very panel that I plan to feed that work shop from, was hiding a problem that had developed over the last 2 years.
Before and After
Here’s a picture of the inside of that panel I took when the house was being inspected. This was 2 years ago.
Very simple panel, nothing mysterious. All work either done or supervised by a licensed electrician.
Here’s a close up of the same panel today. Notice anything different?
Several of the neutral connections have charred/melted insulation and the plastic bracket holding the neutral bar is partially melted. The problem, missed by the inspector (as good and thorough as he was) is that second screw from the bottom. It was looser than the others. This created a gap, which allowed the current to arc, which generated a lot of heat. I have no other explanation. This panel is only fed from a 50 amp breaker and there was no other damage in this box or the main box.
I was able source a new load center from Menard’s and pulled the insert from it. After disconnecting the power to this sub panel, I removed everything from it and replaced the damaged insert as well as any damaged wire.
A little paranoid
That panel cover is going to stay off for a while, with a fire extinguisher close at hand. Even though I am positive I won’t need it, I’m a little on the paranoid side right now.
I also went through and checked and tightened every neutral wire in the both breaker boxes.