I’m in an apt. and the power has been shutting off lately. It doesn’t trip any of the breakers in the breaker box inside the apt. but it does trip the master breaker on the box outside. Thought it was an oven issue but it still happens with the oven breaker off.

Visual inspection of the breaker box outside shows one of the wires looks a bit corroded. Wires to/from the rest of the units are a nice copper color. Is that a red flag?

Landlord is dragging their feet and telling us to talk to the electric company, and electric company is saying to call a licensed electrician, so I’m just trying to understand the issue so hopefully the landlord will listen to me.