Main Panel or Sub-Panel

Question … To stop and think about.

Something I see 2-4 times a month in the Kansas City area. Mostly in semi-rural areas out of town a bit.

Outside close to the service meter is a panel and when you open it there is a disconnect / breaker (100-150-or 200amp).

Inside the home usually in the garage or basement is another panel. Sometimes it has a main disconnect / sometimes not. It most frequently has the neutrals / grounds on same buss bar(s).

In the city the code guys and most electricians treat this as a main panel (outside) and sub-panel (inside) and want to see the inside panels neutrals / grounds separated.

Outside town in rural / semi-rural areas they’re all across the board with how they call it.

Many rural electricians or utility providers call the outside disconnect a “courtesy disconnect” and call the inside panel the main panel AND allow it to follow main panel rules (like neutrals / grounds can be on same buss bar).

Other rural area treat it like its done in the larger cities. I hear discussions going both ways and I know how I treat and write it, but wondering how other treat it.

Your thoughts …

I think there is only one true way to look at it. The outside disconnect at the meter is the service disconnect and part of the service equipment. Anything downstream of that is considered a distribution or sub panel, which requires a floating neutral when feeders are 4-wire. Older 3-wire feeders to sub panels in the same building should’t have neutral separation. At least that is the thinking I have so far.

The inside panel should be fed with 4 wires and have the neutrals and grounds isolated.

Dan, not long ago I made a big effort to get this exact question answered, and from all the creditable sources the answer was the same: The first point of disconnect is the service panel and that’s where the bond between the grounding and grounded (neutral and ground) must take place. The panel in the home is a sub-panel and the neutral must be isolated from the ground.


So far everyone here is in line with my thoughts and reporting, so its amazing to me how many rural electricians or utility providers treat it otherwise.

I’ve written it like this for over 30 years and still have rural electricians, utility providers or even small town code guys, etc tell the buyer I’m nuts and its all ok.

Just rolls off my back cause I know if anybody ever has a problem with this ITS not gonna be my tit in the wringer.

Jim, what do you think about 250.32(B)(2) in the 2005 NEC (and earlier) which allowed the neutral to be used for grounding/bonding purposes at a separate structure? This is prior to the change in the 2008 NEC which required isolation at separate structures.

Dan…I replied to your PM…;)…sorry for the delay as I don’t get on here as much anymore.