230.72 with a twist

[jar546]

In order to keep this in the commercial section, I will call this a 3 unit apartment building:

You have a 3 unit apartment building. An upper and lower apartment on the left side and a full 2 story on the right side.

A single service drop comes from the POCO xfmr to the structure then the single drop comes down to a 3 gang meter on the left side of the building.

The contractor knows he can serve several units from a single drop per 230.40 exception 1

The contractor decides to install a main panel for the left side lower apartment in the common basement which is accessible by all tenants.

He then installs a disco next to the left side lower apartment's main panel. This disco will serve as the disconnecting means for the sub-feed to the full apartment on the right side.

Rather than install another disco inside and run more 4 wire to the left side upper apartment, he decides to run the service cable inside conduit on the outside of the building up to the 2nd floor to another main panel with an integral main disconnect. This saved him the expense of 4 wire and a disco.

The issue is 230.72 grouping.

Since this is 1 single drop and we are utilizing 230.40 exception 1, we need to group the discos and in order for the 2nd floor disco to be compliant it will have to be grouped next to the others in the basement.

I am being told that exception 1 in 230.40 allows this disco to be away from the others and supply the 2nd floor apartment.

In my opinion, the only way that we can eliminate having to group these disco's is to have a separate service for each apartment such as a transformer with 3 laterals coming from it.

Thoughts?

 

[chris kennedy]

Re: 230.72 with a twist

I am being told that exception 1 in 230.40 allows this disco to be away from the others and supply the 2nd floor apartment.

If your disco's are grouped at the 3 gang meter bank then what you have running to the panels are feeders. Since you are running SE cable into the units and that is the first means of disco I don't see a problem.

Service. The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served.

The above definition ends at the first means of disconnect. So the second floor service is itself a separate service.

 

[jar546]

Re: 230.72 with a twist

There are no disco's at the exterior triple meter base.

Disco 1 for the lower left apt is in the basement as part of the main panel

Disco 2 for the right side apt is in the basement and the subpanel is in the apt

Disco 3 for the upper left side apt is in the main panel inside the apt

Disco's 1 & 2 are grouped together in the common basement

Disco 3 is by its lonesome and not grouped at all.

There is only 1 service to the building. One OH drop from the POCO

Do all 3 need to be grouped together?

 

[RJJ]

Re: 230.72 with a twist

I don't believe this complies base on the set up you described! My understanding is you need the fourth wire. I will run this past my electrical guys down here and get back.

 

[dcspector]

Re: 230.72 with a twist

Do all 3 need to be grouped together?

Jeff if I have all this that you explained in my "li'l pea head".......Yes.

 

[jar546]

Re: 230.72 with a twist

I don't believe this complies base on the set up you described! My understanding is you need the fourth wire. I will run this past my electrical guys down here and get back.

If you run the upper left apartment service cable on the outside from the meter base then it does not have to be a 4 wire as the disconnect will be at the panel where it enters the 2nd floor apartment. 4 wire cables are for the load side of the service disconnect.

 

[RJJ]

Re: 230.72 with a twist

Then I must read this grouping again! I must have misunderstood the set up. I agree with the load side and 4 wires!

 

[Mr. Inspector]

Re: 230.72 with a twist

230.40 refers only to service-entrance conductors, not disconnects. The disconnects must be grouped.

 

[jar546]

Re: 230.72 with a twist

230.40 refers only to service-entrance conductors, not disconnects. The disconnects must be grouped.

Try to tell that to the electricians over at Mike Holt's forum.

 

[dcspector]

Re: 230.72 with a twist

230.40 refers only to service-entrance conductors, not disconnects. The disconnects must be grouped.

Try to tell that to the electricians over at Mike Holt's forum.

That is one of many reasons why I do not participate on the M.H. Forum any more. I like to read the threads then leave. Hey its better than watching re runs on Comedy Central at night :mrgreen:

 

[TheElectricalGuru]

Re: 230.72 with a twist

You are 100% correct.....Article 230 is broken down into 7 parts and many people will confuse the issues with 230.40 and it's exceptions with the grouping requirements of Article 230.72. The grouping has to do with the disconnection means at the end of each SET permitted by 230.40 . Ex 1 for example.

I truly see those sections within Article 230 messed up constantly and most certainly on that website where the ego's are higher than the education factor.

 

[north star]

Re: 230.72 with a twist

Paul [ aka - ' The Electrical Guru ' ],

Welcome to the codes forum! What took you so long to post on here... ?

 

[EPrice]

Re: 230.72 with a twist

Well, I guess I'll voice the minority opinion and say that 230.40 Exception 1 along with 230.71(A) do allow disco 3 to be away from the other discos. Here is why I say that: 230.40 allows a separate set of service entrance conductors to be "run to each occupancy or group of occupancies". How would it be possible to run a set of service entrance conductors to each occupancy and still keep the disconnects in one location, since by definition, the service entrance conductors end at the disconnect? 230.71 (A) allows a group of up to 6 breakers for each set of service entrance conductors. 230.72 requires all of the breakers in one set of up to six to be grouped, but it does not say anything about keeping one set of 6 in the same location as another set of 6.

Edit to add: Though 230.2(E) doesn't specifically address the situation we are discussing here, I would try to stretch it to require the permanent identification at each disconnect location.

 

[McClary's Electrical]

Re: 230.72 with a twist

Well, I guess I'll voice the minority opinion and say that 230.40 Exception 1 along with 230.71(A) do allow disco 3 to be away from the other discos. Here is why I say that: 230.40 allows a separate set of service entrance conductors to be "run to each occupancy or group of occupancies". How would it be possible to run a set of service entrance conductors to each occupancy and still keep the disconnects in one location, since by definition, the service entrance conductors end at the disconnect? 230.71 (A) allows a group of up to 6 breakers for each set of service entrance conductors. 230.72 requires all of the breakers in one set of up to six to be grouped, but it does not say anything about keeping one set of 6 in the same location as another set of 6.Edit to add: Though 230.2(E) doesn't specifically address the situation we are discussing here, I would try to stretch it to require the permanent identification at each disconnect location.

230.40 ex 1 is for "different characteristics" which doesn't apply here,,,,all these are the same voltage.

so that takes you back to 230.71 up to six

which takes you yo 230.72 to which the only ex is for firepumps, so yes your setup is in violation.

 

[EPrice]

Re: 230.72 with a twist

Well, I guess I'll voice the minority opinion and say that 230.40 Exception 1 along with 230.71(A) do allow disco 3 to be away from the other discos. Here is why I say that: 230.40 allows a separate set of service entrance conductors to be "run to each occupancy or group of occupancies". How would it be possible to run a set of service entrance conductors to each occupancy and still keep the disconnects in one location, since by definition, the service entrance conductors end at the disconnect? 230.71 (A) allows a group of up to 6 breakers for each set of service entrance conductors. 230.72 requires all of the breakers in one set of up to six to be grouped, but it does not say anything about keeping one set of 6 in the same location as another set of 6.Edit to add: Though 230.2(E) doesn't specifically address the situation we are discussing here, I would try to stretch it to require the permanent identification at each disconnect location.

230.40 ex 1 is for "different characteristics" which doesn't apply here,,,,all these are the same voltage.

so that takes you back to 230.71 up to six

which takes you yo 230.72 to which the only ex is for firepumps, so yes your setup is in violation.

230.40 Exception No. 1 states: "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."

How is that for "different characteristics"? I think you are getting confused with 230.2(D) which allows more than one service because of "different characteristics". The OP wasn't talking about more than one service, he was talking about more than one set of service entrance conductors supplied by one service, run to different occupancies; just what 230.40 exception 1 is talking about.

We don't need an exception from 230.72, since 230.72 doesn't even address the location of the multiple disconnects, but only requires that the up to 6 breakers that constitute one disconnect be grouped.

 

[chris kennedy]

Re: 230.72 with a twist

230.72 doesn't even address the location of the multiple disconnects, but only requires that the up to 6 breakers that constitute one disconnect be grouped.

No? What does 230.72© say?

 

[TheElectricalGuru]

lol...did not know it existed...would be one reason.

FYI...My site is named that.....My name is actually just Paul..

 

[EPrice]

No? What does 230.72© say?

lol...did not know it existed...would be one reason.FYI...My site is named that.....My name is actually just Paul..

230.72© really doesn't say where the disconnects are to be located, only that the occupant needs to have access to the disconnect serving his occupancy. It certainly doesn't say that the multiple disconnects need to be grouped with one another.