Grouping of disconnects in 230

[ivsenroute]

This situation was discussed today (although briefly) concerning grouping of disconnects on townhouses and duplex units. Still nothing concrete or clear from the discussion at our IAEI annual spring seminar today.

Here is one situation:

A duplex, up and down with 1 service drop to a 2 gang meter base on the left side. Can you run from the meter to the basement for the lower unit with a main panel/disco then run from the 2nd meter outside the building up to the 2nd floor unit with another main panel/disconnect?

What is your NEC opinion?

 

[LarryFine]

Can you run from the meter to the basement for the lower unit with a main panel/disco then run from the 2nd meter outside the building up to the 2nd floor unit with another main panel/disconnect?

Yes, because each feeds a separate premises, as long as each follows the 'nearest point of entrance' rules your locality enforces.

 

[chris kennedy]

Yes, because each feeds a separate premises

I disagree Larry, still one service in the eyes of the NEC.

 

[ivsenroute]

Right of the bat we have a disagreement and this is one of the most debated areas of the code. I truly wish we had an official interpretation from the code panel on this subject with different situations.

 

[LarryFine]

Right of the bat we have a disagreement ...

Just doing our part.

 

[kwired]

Around here you would likely need to have a two hour finish between the units to even consider having 2 services - essentially making them two separate buildings for fire code reasons. That would be typical for side by side units, in a duplex I'm not certain if stacked dwelling units would be the same.

 

[ivsenroute]

Around here you would likely need to have a two hour finish between the units to even consider having 2 services - essentially making them two separate buildings for fire code reasons. That would be typical for side by side units, in a duplex I'm not certain if stacked dwelling units would be the same.

Yeah that's great but the question is for when there IS 1 drop to a 2 gang meter whether or not the disconnects have to be grouped. Looking for opinions for this situation. No need to bring in fire code requirements when the question is already spelled out.

 

[hurk27]

I believe 230.40 can confuse this, as exception 1 states that the service entrance conductors can run to each occupancy, remember SEC's are before the service disconnect (See the diagram in 230.1)

Exception No. 1: A building with more than one occupancy shall be permitted to have one set of service-entrance conductors
for each service, as defined in 230.2, run to each
occupancy or group of occupancies.

Indiana has used this exception to allow disconnects to be located by each occupancy when dealing with more then one dwelling or occupancy in same building.

Basically this is saying that the grouping of service disconnects only apply to single occupancy buildings?

A few years back Charlie Eldridge, posted a sketch of this on one building showing how multiple groups of service disconnects could be installed on the same building, I'll try to find it if I can.

 

[ivsenroute]

Thanks, appreciate the help.

 

[acrwc10]

This situation was discussed today (although briefly) concerning grouping of disconnects on townhouses and duplex units. Still nothing concrete or clear from the discussion at our IAEI annual spring seminar today.

Here is one situation:

A duplex, up and down with 1 service drop to a 2 gang meter base on the left side. Can you run from the meter to the basement for the lower unit with a main panel/disco then run from the 2nd meter outside the building up to the 2nd floor unit with another main panel/disconnect?

What is your NEC opinion?

One service drop equals one service with two meters. The disconnects need to be grouped. I believe in one of the Mike Holt drawings it shows a similar situation and the meters and disconnects are in the same location.

 

[kwired]

Yeah that's great but the question is for when there IS 1 drop to a 2 gang meter whether or not the disconnects have to be grouped. Looking for opinions for this situation. No need to bring in fire code requirements when the question is already spelled out.

What does the meter(s) have to do with anything? They are simply devices that are allowed to be installed on the supply side of the service disconnect(s). The issue is the location of the service disconnect(s) no matter how many meters or serviced drop or lateral conductors there are.

If separate services in separate locations are allowed the meters can be grouped, they can be separated, they can even be on a separate structure, like the utility company pole.

I still say that any place that is allowed by NEC to have multiple services to each occupancy of a building will also have building/fire codes requiring a minimum finished rating between occupancies, which essentially makes them separate buildings.

Now if you have multilevel buildings with separate occupancies above others the fire codes may not be the same as for one level buildings. At the very least I would think that the same material that is allowed in a wall to provide a certain fire rating is not necessarily going to provide the same rating for the same amount of time if installed on a ceiling.

 

[mpd]

230.40 exception #1 allows one set of service entrance conductors to be to be run to each occupancy, 230.71 is the maximum number of service disconnects for each set of service entrance conductors permitted by 230.40 exception #1, the grouping in 230.72 applies to the 2 to 6 service disconnects permitted in 230.71 for each set of service entrance conductors

if i had a 6 gang meter socket, i could run 1 set of service entrance conductors to each unit put a wireway and install 6 service disconnects in that unit those 6 would have to be grouped in that unit

 

[ivsenroute]

230.40 exception #1 allows one set of service entrance conductors to be to be run to each occupancy, 230.71 is the maximum number of service disconnects for each set of service entrance conductors permitted by 230.40 exception #1, the grouping in 230.72 applies to the 2 to 6 service disconnects permitted in 230.71 for each set of service entrance conductors

if i had a 6 gang meter socket, i could run 1 set of service entrance conductors to each unit put a wireway and install 6 service disconnects in that unit those 6 would have to be grouped in that unit

So your opinion in the case that I presented is that the disconnects do not have to be grouped?

 

[don_resqcapt19]

So your opinion in the case that I presented is that the disconnects do not have to be grouped?

That would be my opinion of what the code rule requires. The disconnects for one set of service entrance conductors are not required to be grouped with the service disconnects for other sets of service conductors. Each set of service entrance conductors can have up to six disconnects.

 

[elohr46]

230.40 exception #1 allows one set of service entrance conductors to be to be run to each occupancy, 230.71 is the maximum number of service disconnects for each set of service entrance conductors permitted by 230.40 exception #1, the grouping in 230.72 applies to the 2 to 6 service disconnects permitted in 230.71 for each set of service entrance conductors

if i had a 6 gang meter socket, i could run 1 set of service entrance conductors to each unit put a wireway and install 6 service disconnects in that unit those 6 would have to be grouped in that unit

I agree with your post provided the SE cable were run outside the building and the disco's were installed per 230.70(A)(1).

 

[LarryFine]

I agree with your post provided ... the disco's were installed per 230.70(A)(1).

That's satisfied as each tenant's disco is within their respective premises.

 

[mpd]

and if I had a PV system that was supply side connected, I could also have 6 more disconnects grouped for each set of service entrance conductors that do not have to be grouped with the service disconnects in that space, per 230.40 exception #5, 230.71 (A)

 

[ivsenroute]

It appears as though grouping of disconnects would not be required in the case stated in the OP.

Although a poor method, it is allowed and no grouping required.