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Didn't look like a bad job to begin with. A few 30 amp breakers on 12 gauge wire but no biggie. Got to looking at the wire and found a few mwbcs so I went to sort those out. I found that there were to few of neutrals on some of the circuits and some mwbcs were on the same phase. While I was finding what neutrals went where I ran into a big problem. I have 4 circuits with two neutrals that have a big problem; three of the circuits share one neutral, twocircuits share one neutral and one of the four circuits share both neutrals. Each circuit operates fine on its own and all the currents add up on their respective and shared neutrals like they should. The ballasts are ge multi volt ballasts so that explains why the lights all operate perfectly but the math still doesn't work. There is also several neutrals grounded out in the wiring making all of the conduits carry current.

Then I found on the outlets in the area there are 3 circuits sharing a neutral. I put a 9.8 amp load on one circuit and had 9.8 returning on the grounded conductor. I put a 2 amp load on another's circuit on the other phase and had 2 amps returning on the grounded conductor. I turn on both and I get 9.6 amps on the grounded conductor. I move the circuits to the same phase and turn on the loads and get 10 amps on the grounded conductor. Math isn't working here. I added a 5 amp load to the third circuit and it does the same thing.

After seeing the work that the electricians used to do here it doesn't suprize me that it is all messed up but the fact that the math isn't working is confusing me. I can't figure out what to go look for. I will just have to open everything up.

Also what are these qo breakers with the odd clip. These are all 30s.

Most of the breakers are so old they don't have the trip indicator or the size cast in the handle. One even says Cedar Rapids iowa instead of Detroit.