Hi, fairly new to the forums, but I feel like I need another set of eyes. I did a complete rewire with a 200A service about a year ago. Recently the customer has been coming home after work and finding several circuits off throughout the house. They aren't in the tripped position, they're off. It's a Siemens panel with seimens breakers. Both standard single poles, and arc faults. She also complained of certain circuits going out, and then power coming back on by itself. I went to troubleshoot, B phase was dead in the panel. Went to check the meter socket, and found that the meter actually wasn't plugged in all of the way. PECO had recently replaced the meter with a smart meter. Made sense to me. That leg wasn't getting a good connection which would cause arcing and possibly a surge causing breakers to trip into the off position. Problem solved. Customer calls me back a week later. Same problem, and now lights are dimming throughout the house on different circuits. Sounds like a loose neutral. Now I wired the panel myself, but I went back, checked all of the connections, everything is tight. Service is grounded properly. Taps are tight. So now I'm thinking that it's a PECO neutral problem. PECO went there today and tested the load side of the meter. Said everything checked out, but they didn't check the load side of the transformer. I'm going back tomorrow and I'm going to disconnect the service ground and then test for voltage at the meter. If they did lose the PECO neutral, we both could have been getting a false reading through the ground. If that turns out not to be the case, I'm at a loss. I don't know what else it could be. Can a bad arc fault cause other breaks to nuisance trip? I'd appreciate any suggestions. Sometimes a second set of eyes comes in handy.