Two main disconnects for 1 service

Hi, the property in question used to have two separate meters (main house and apartment). There is now one meter. From that meter two service lines travel two separate locations in the house (basement and second floor). Each meter has its own 100 amp disconnect.
Is this acceptable?
Thank you

Lots of missing information here I think for context but I’m trying to interpret the information you gave to help if I can. You said there were two separate meters, but now only one of them is in use and it has a 100 amp (service) disconnect at the meter location, and I assume the other meter is abandoned. So now the main house and second floor apartment each have a feeder to their own subpanel from a shared 100A service?

Having a 100 amp service isn’t usually adequate power for most modern houses but not knowing the size or more importantly the loads being serviced that’s a really difficult determination to make. Without pictures and more information I’m not sure what else can be said.

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The way I read this is that there are 2 separate main service panels at 2 different locations inside the house. It seems like there should have been a main panel at the meter with 2 - 100 amp feeds to the interior panels. This would make the interior panels sub-panels.

Sorry for the confusion.
Yes two separate meters initially. Each one had its own main panel inside the building (typical around here). Now there is only one meter, but two lines still going to each main panel with their own respective disconnect. Each panel services a limited section of the house. Each panel is wired as a main panel (neutral and ground bonded). Is this ok? Or do they need to install a main disconnect and treat each panel as a sub now?

It’s not clear where the main disconnects are. The title indicates there are 2 main disconnects but the post indicates a main disconnect at the meter and only one meter in use. So, where is the other disconnect?

if the meter disconnect “kills” both panels then they are both subpanels regardless of where the second disconnect is.

Each panel has its own disconnect (100 amp). Question is if this is acceptable or do they need a single disconnect and then treat each one as a sub. I try not to over prescribe repairs especially for these lower income house, but want to make sure everything is safe.

If you have a concern with the modification (meter rewiring) you should just refer it out to a sparky and not try to present a solution.

I’m not trying to present a solution to them. I am asking if this is acceptable? To have two service disconnects on one service line? Or does it need to have a single disconnect?
This is the only thing that is proving to be a concern. I am trying to avoid telling them to hire an electrician for something that is not a problem, but if it is a problem, then yes Sparky should know what to do.

It used to be done with remote panels. There are too many considerations without seeing exactly how it was done.

I can make up in my own head why this is wrong, but I am not always right. Mainly to me it seams that to shut down the entire system it will require more than 6 turns of the hand, or how ever that is worded. But there are two sections of the house. So in theory each panel with the correct disconnect installed will correctly shut down the appropriate line, but not the entire service. Does this make sense?

Ok sounds like this should get kicked on down the road to Sparky.
Thank you for trying to help.

You can have up to 6 throws to turn off power to a single service. So if there are 2 disconnects on the outside at the meter and two remote panels, not a problem as long as everything is wired correctly. The question you should clarify is how many disconnects are by the meter. Even if there is 1 disconnect at the meter, that is the service and the two panels inside the building should be wired as remote distribution (sub) panels. If there are two disconnects on the outside 100amp each, then the rating of the service would be determined by the service entrance conductors.

There are 0 disconnects by the meter. The disconnects (100 amp each) is located inside each panel which is located inside the house. So to clarify- main service comes to the meter array (three possible meters but only one now). Then from the single meter two wires run off in two different locations inside the house. Both are wired as a main service panel with disconnects.

I would attach photos but my internet is so bad I can not upload today (the gerbils are not running as hard today I guess)

A dwelling cannot have 2 service panels inside in two different locations. They have to be grouped (their disconnects). There are also very! specific rules on how you can run unprotected SE conductors inside a building. This needs to be called out and inspected by a licensed electrician ASAP.

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Thank you, I believed that was the case, but wanted to check.

There are several requirements, first as Simon stated the two service disconnects (the panel main CB’s) need to be grouped at one location so if the two panels are next to each other that it is okay. Secondly, (as Simon also stated) the service entrance conductors cannot run very far into the structure. The NEC doesn’t set a distance but most jurisdictions will allow only a few feet so if the panels are not inside opposite the meter then that is a problem. Thirdly, if you put a new service disconnect next to the meter then you would need to change the 3-wire to a 4-wire feeder, separate the neutrals and EGC’s and move the Grounding Electrode Conductors (GEC’s) to the new service disconnect.

Sounds like you need an electrician to sort it all out.

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yeah! Adam,
this is an interesting topic. As you can see/read… there are so many interpretations and opinions here. Please! take a ‘sequential’ set of pictures from the service drop and following the route to those referenced panels and disconnects. You know, I am sure, electricity flows in one direction IN to the distribution panels where the loads are balanced and then back out (returns). With this orderly set of pics we can expand our points of views and share and ALL learn from your contribution. Having the “routing” clear, it is easier to evaluate what needs to be ‘on-the-way’ (main disconnects, internal residential unit disconnects, circuit breaker panels and sub-panels, etc.) At some point in time, it seems, that this dwelling had a different purpose than in the current times. Thereof, the NEC requirements and codes may have been different. An extra disconnect breaker here or there does not hurt, for purposes of maintenance or even residents safety in case of emergencies. you may or may not need an additional sub-panel disconnect breaker close by the second kitchen in a basement residential unit, but it does not hurt to add one and avoid having the tenant to run out to the basement central entry point to look for an unfamiliar breaker located within NEC codes down there. You see! electrical installation design responds to the life events that are planned to take place in the dwelling… Contractors will do the bear-minimum to save on their budget, but I usually recommend upgrades to fit the current situation. Just inspected a 3 apartment multi-unit in downtown West Baltimore for an investor that plans to rebump/upgrade those units. Found no Main disconnect inside the individual units. Can you imagine a tenant having to identify witch breaker to knock down if the electrical stove is on fire. No legend on the panel to make it worst. Does He/She know that the main disconnect for his/her unit is down at the rear wall of the basement? Does he/she has access to such basement area?
You have ‘homework’ to do…!

I want to say yes this is legal.(Without pictures). They use what’s called a tap rule and it’s perfectly acceptable if they’ve stuck to the code. It’s been many years since I was in the electrical trade, but I’ve done this myself in the past. It’s hard to say what current code is because it does change every few years. (And depends on which state you’re in ) My advice is to get an electrician or recommend electrician just to cover your tail.

I should say if the secondary breaker is fed from the service conductors. If it’s fed from 100 amp breaker within the panel and yes perfectly legal as well.

A few pictures would help a lot.

If BOTH disconnects are at the single meter AND labeled, I would not view that as a defect in need of correction. The bonded neutral and ground at the subpanel is allowed TODAY if it was allowed at the time of construction.