Today’s inspection, 3,941 sq ft, built in 2015, underground lateral. In the garage was what appeared to be a main panel with another panel right beside it that said “service disconnect”. It appeared as though the service disconnect was legit, but the main panel beside it was wired up like a main panel, not a sub panel. To add to the conundrum, there was a subpanel on the other side of the basement, wired up as a sub panel, but the feeders to it were like those going into the “service disconnect”. I’m a little unsure of what I’m looking at and am wondering if anyone has seen this setup before. The first photo is the main panel and the “service disconnect”, the second photo is the sub panel. Any input would be appreciated!
More details are needed. Did the meter have 2 feeds out? This might simply be two service panels grouped as required.
The meter was backed up against the wall on the exterior to where the “service disconnect” was located.
From what you describe, it appears that the house has 400 amp service, assuming both disconnects are 200 amp each.
The disconnect is for the panel on the other side of the basement. The reason for the disconnect is so there isn’t an energized wire running through the house that doesn’t have over-current protection.
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This was argued a few months ago… The bonding location (with GEC) is at the main disconnect. Therefore, there should be four-wire feed with grounds and neutrals isolated in every panel downstream, including the main panel. The primary issue is that the EGC between the disconnect and main panel can (will) become electrified. Plus, if something happened to the neutral service (grounded) conductor, the EGC acting as the neutral could become over-fused and potential fire hazard being a smaller gauged conductor.
Hey Kevin, it’s hard to see in the photos, but the “service disconnect” had a 150 Amp breaker and the larger main panel has a 200 Amp breaker.
Hey Brian, thanks for the insight. I’ve always treated any panels past the main disconnect as remote “sub” panels and expected the grounds and neutrals to be isolated with the grounds bonded to the panel. The remote panel on the other side of the basement is setup this way.
What confused me was 1.) the lack of remote setup in the main panel, 2.) the feed to the sub panel on the other side of the basement looking to have the same wiring as that which is coming into the service disconnect, and 3.) the main panel breaker being larger than that of the service disconnect.
You did verify that the disconnect on the right de-energized the panel next to it or is it just the disconnect for the remote panel in the studs, which does look proper for a remote?
Otherwise the neutrals and grounds shouldn’t land on the same terminal strip as you mentioned in that panel with all the breakers.
Hey Mark, No, I did not flip off the “service disconnect” breaker. I wasn’t sure what it controlled. Also, I usually don’t flip off power to the whole house, and as such, I wasn’t comfortable turning it off.
I’ve heard it said that a panel within 5 feet of a main disconnect can still be wired as a main panel, but I haven’t seen any documentation to verify the statement.
Then that would make it 350 amp service for the house. I usually see either 150+150=300 amp or 200+200=400 amp service. I often see this type of set-up.
I’ve never seen 200+150=350 amp service, until now. 
I don’t either, I wasn’t suggesting you do so, specially if anyone lives there. You’re in dutch if the breaker won’t reset.
I just meant, can you see down the conduit to see if they connect or go out to the meter, which seems like what’s happening here.
I tried looking into the conduit on the main panel and the service disconnect to see if there was any way I could tell they were connected, but I wasn’t able to see anything. Since the panels are mounted on an exterior wall it’s hard for me to visualize them connecting together through any type of conduit so it’s suspected they are using the exterior meter as a conduit. However, I couldn’t verify any of this by looking at the panels or the exterior meter box.
There is only one set of feeders coming off the disconnect on the right. They appear to match up with the feeders entering the basement panel, which is set up as a sub, as it should be. That means the garage panel on the left is most likely being fed directly from the meter.
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Hey Ryan, so the main panel AND the “service disconnect” are being fed from the meter and the 150A breaker feeds the sub panel. Ok, that would make sense. The “service disconnect” label on the small panel to the right threw me off and had me thinking it was for the whole house, that and the sheathing on the wires going to the sub looked like exterior sheathing.
That’s my take, based on the pictures. It’s hard to understand how it ended up this way, as it is not typical. Was there a big addition put on at some point?
The basement was partially finished with the sub panel sitting in the unfinished portion on the right side. The sub controlled the basement and right side of the house on the main level (kitchen and master br.) The main panel handled the left side of the main level and the upstairs. The house is only 9 years old with no modifications listed in any of the records.
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That’s the most likely scenario given that the breaker and the panel are fed with only 3-wires. The single service disconnect is there because it is required to be grouped in the same location as the service disconnect in the panel.
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