200 amp? Never seen this before

I’ve never seen this before so I’m hoping somebody can explain what’s going on so I can better understand it as well as explain it to my client. There’s a 200 amp service cable coming into the home and then to a distribution box below the panels. When I remove the dead front covers, it looks like one hot wire is coming into each panel. However, the panel on the right has a 100 amp breaker leaving the panel and going back down into the distribution box. Panel on the left also has a 100 amp main breaker that has two conductors coming off of it and going back out into the distribution box


as well. Anybody able to explain this?

Welcome to our forum, Justin!..enjoy participating. :smiley:

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Was there a whole house generator or service disconnect out side?

Where is this one hot wire in your picture?

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I see two hot wires and a neutral coming from the splitter box going to each distribution panel / breakers. Was there a service disconnect nearby?

I see 3 conductors entering each panel from the gutter, (split bus on the right).

Maybe that is what is confusing him

I dont think they are split bus panels, but they are being supplied by back-fed breakers. The panels appear to be identical, but The single conductor you are referring to as the feeder is the neutral (at the top) The 2 ungrounded conductors are feeding a back fed breaker on both panels.
The one on the left is fed at the top breaker, the one on the right is fed halfway down on the left.

Larry, Thanks for the welcome. I did not see a whole house disconnect or hook up for a generator outside.

Ryan and Marcel, I think I mistakenly identified the single neutral wire coming in at the top of each panel as a hot wire. This probably confused all of you guys as much as it confused me. That’s my fault. Sorry about that.

Daniel, If both of these panels are being fed by back fed breakers, what Is the function of the 100 amp breaker in the right panel on the top right side? I have to assume that it is a split bus panel and that that 100 amp breaker shuts down the right side but I’ve never seen anything like this before so I’m afraid to make any assumptions.

Thanks everyone for the feedback. As always, I learn a lot in these discussions.

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The back-fed 100 amp breaker is the service disconnect, one for each panel. Did you open the wireway below and take a picture?

A good deal of the confusion is caused by the “mislabeled” wires. White as hot and black as neutral. A real rat’s nest with no upgrade capacity.

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If you are referring to the one at my arrow below, it appears there may not be any conductors connected to it. It is not being used to feed the panel. Conductors may have been too short to reach it.

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I think that you’re correct, the conductors from the nipple appear to go to the back fed CB on the left. Some other photo’s would help to confirm this.

Robert, I did not open the wire way below the panels which in retrospect, I should have just to investigate a little further.

Ryan, what you’re saying makes sense if the wires were indeed too short. Does anybody know if this is a legit way to set up a panel? Again, I’ve never seen this before and as Robert alluded to, it looks very haphazardly installed. I’m thinking I need to refer an electrician out to evaluate this further but I wanted to get some input from other professionals that may have run into similar situations before before I did that.

I can’t imagine why it would be an issue as long as the labeling for the panel is correct. It should be clear which breaker is the main disconnect. Also there should be a hold-down device on the breaker that is feeding the panel.

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That’s a rat’s nest. Ryan and Robert are correct, the junction box below has divided the service feed into two main breaker panels (would be interesting to see how they did the junction box wiring.) The top left is run to the factory MCB at the top, but on the right panel they appear to have left the factory MCB unwired and used a branch mounted back fed 100A breaker as the main instead. I can’t see a hold down device for that back fed main, and mounting two twin breakers opposite it is not a particularly good idea either because that spot on the bus bar can potentially be stressed due to heat.

At a minimum I would have wanted the mains clearly labeled for safety, it would be too easy for the homeowner to mistake throwing the top mount breaker in the right panel and think they have safely disconnected the power only to discover the shocking truth too late.

Were they labeled on the dead front cover?

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Without seeing what’s going on in the junction box or wireway below, it’s hard to figure out for sure what’s going on here. It’s possible that the panel on the left could very well be a sub-panel fed from the 100 amp breaker installed in the middle of the panel on the right.

Was there another sub anywhere?
Was there an electric furnace?
My WAG is all those 20 amp breakers in the LH panel are feeding baseboard heaters.

Daniel and Robert have it correct, back fed panel on the right. Not split bus panel

You cannot see a Square D breaker holddown even when installed.

I see a 200 disconnect. Left panel. Seeing the amount of double pole breakers in the left panel I suspect it is for an out building. No lighting circuits.

Explain what type of electrical equipment the panels are serving and where.

All,

  Neither of the panels were labeled correctly at all. There was no other sub panels in the home and there was not one in the out building either. Most of the double pole breakers appear to be serving electric baseboard heaters.

Robert,

 You mentioned you could see a 200 amp disconnect in the left panel. The only disconnect that makes sense to me is the 100 amp MCB in the top right corner at the left panel. I’m not seeing it. I really should have pulled the wire way apart and investigated it further so I could make this a little more clear for all of us. Can you tell me exactly where in the left panel the 200 amp disconnect is located?