Conn. installation

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pierre

Senior Member
I received a call today from a Conn. contractor about grounding multiple service disconnects. In the discussion he mentioned that the 2 service disconnects were located in two different parts of the building, not visible from each other. That distracted me from his original question. I made mention of grouping service disconnects, but he said the inspector already approved the locations.

I am wondering if the state of Conn. has a local law that permits the disconnects for a building not to be required to be grouped.
Are there any Conn. people here who may know that answer?
This is the Stamford area of Conn.

Thanks,
Pierre
 

mc5w

Senior Member
Re: Conn. installation

If service switches for a single tenant are not grouped there has to be a permanent plaque at each service that reads " service switch x of y other services switches located blah blah blah".

If a tenant has a large enough area they are allowed 2 or more services in different locations. In this case there has to be permanent plaque at each service indicating where the other services are located.
 

bphgravity

Senior Member
Location
Florida
Re: Conn. installation

If these are indeed two separate services or two service disconnects remote from each other, the grounding electrode system will still be required to be common between them. This does create a hazardous condition, but it is still required. See section 250.58.
 

pierre

Senior Member
Re: Conn. installation

Thanks for those answers, but I really would like to know:

My concern is not the code requirements, but in fact if the State of Conn. has local laws that permit this.
It is a small building with a body shop and a small garage with two different owners for each small business.
Does Conn. permit the service disconnects to not be grouped? Both of the service disconnects originate at the same Utility service drop, they are about 60 feet from each other and not at all visible or accessible to each other.
 

iwire

Moderator
Staff member
Location
Massachusetts
Re: Conn. installation

I believe the NEC permits this installation.

From your description you have one "Service"

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

Service Conductors. The conductors from the service point to the service disconnecting means.
The two sets of service conductors each may have up to six disconnects and the two sets can not be grouped.

230.71 Maximum Number of Disconnects.
(A) General. The service disconnecting means for each service permitted by 230.2, or for each set of service-entrance conductors permitted by 230.40, Exception Nos. 1, 3, 4, or 5, shall consist of not more than six switches or sets of circuit breakers, or a combination of not more than six switches and sets of circuit breakers, mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. There shall be no more than six sets of disconnects per service grouped in any one location. For the purpose of this section, disconnecting means used solely for power monitoring equipment, or the control circuit of the ground-fault protection system or power-operable service disconnecting means, installed as part of the listed equipment, shall not be considered a service disconnecting means.
Take a look at Exhibit 230.4 in the 2002 NECH.
 

hess

Member
Re: Conn. installation

these two services is no violation since each part of this building is owned by a different person, local building codes may require a 4 hour fire wall to separate the two business.
 

pierre

Senior Member
Re: Conn. installation

Good morning Bob

Please try to explain to me which of the exceptions in 230.40 could be referenced, and how they apply to 230.2
You can exclude 230.40 exceptions 1, 3, 4, 5 as they do not pertain to this installation. :D

#1. This is a small building that does not meet the requirements of (A), (B), (C) or (D).

#3. Dwelling - this is not a dwelling

#4. Dwelling - this is not a dwelling

#5. this section does not apply.

So how does #2 work for this installation?
BTW I am referencing the '02.

Your reference:

"230.71 Maximum Number of Disconnects.
(A) General. The service disconnecting means for each service permitted by 230.2, or for each set of service-entrance conductors permitted by 230.40, Exception Nos. 1, 3, 4, or 5, "

Notice how exception #2 is not referenced here.

"Exception No. 2: Where two to six service disconnecting means in separate enclosures are grouped at one location and supply separate loads from one service drop or lateral, one set of service-entrance conductors shall be permitted to
supply each or several such service equipment enclosures."

The handbook has a lot of illustrations, I am not too sure how this works for the installation I have mentioned.


The building has one owner who is renting a portion of his building to the other business owner, one address, no fire walls.
Sort of like an office building that rents portions of the building to different businesses.

[ May 14, 2005, 08:55 AM: Message edited by: pierre ]
 

iwire

Moderator
Staff member
Location
Massachusetts
Re: Conn. installation

Pirre I have not seen your building so its a tough question. Have you seen the building?

It looks to me that if the AHJ is aggrable this could apply to any building.

Exception No. 1: A building with one or more than one occupancy shall be permitted to have one set of service-entrance conductors for each service of different characteristics, as defined in 230.2(D), run to each occupancy or group of occupancies.
230.2(D) Different Characteristics. Additional services shall be permitted for different voltages, frequencies, or phases, or for different uses, such as for different rate schedules.
It also looks to me as it is up to the AHJ to determine what exactly is a 'different use'. :D
 

pierre

Senior Member
Re: Conn. installation

I have not seen the building. I absolutely agree that the AHJ who has been to the site knows a lot more than the person who only has a description of what is going on. I am not disagreeing with him, I am just wondering if there are some differences in local law.

I do not see any differences in 230.2(A) special conditions, (B), (C) or (D). From the description this is a small building that now has two different businesses (both are using the same phase/voltage/amperage/characteristics) - where neither wants to pay for the others electric consumption so an additional service was added. In my opinion this additional service disconnect should be grouped with the original.

But I am open to discussion... as I always want to learn/change my ideas if I am wrong.
 

hmspe

Senior Member
Location
Temple, TX
Occupation
PE
Re: Conn. installation

Pierre,

I can't speak to Connecticut's requirements, but here in Arizona what you've described would not be allowed, at least as a general rule. Of course, I just had a project in a rural area where the contractor replaced the 800A single S.E.S. on a new design for a two tenant office building with a 400A all-in one for one tenant and a 200A all-in-one for the other. The power company REQUIRED him to separate the services by about 40', and the inspector OK'd it. My interpretation of the Code is that the two all-in-ones would be OK if they were adjacent, but 40' apart, no way.

The only possible justification I can see for your situation is 1999 230-2(b)(1), if the AHJ determined that there was no available space for the second service. I'm picturing an old brick building with a lot of large windows....

iwire -- At least in this part of the country the meter and service disconnect(s) are part of the "service". The phases part of 230-2(d) refers to having, for example, a single phase and a three service on a building, and "different uses" is clarified in the Code text as referring to things like different rate schedules. There's nothing that I can find that allows different OCCUPANCIES (ie., a bank next to a commercial garage) as a sole basis for allowing multiple services. "Use" and "occupancy" aren't interchangeable terms.

Martin
 

George Stolz

Moderator
Staff member
Location
Windsor, CO NEC: 2017
Occupation
Service Manager
Re: Conn. installation

I don't think there's enough info to judge this fairly.

</font>
  • <font size="2" face="Verdana, Helvetica, sans-serif">We don't know how many sets of service conductors are feeding these services.
    Both of the service disconnects originate at the same Utility service drop, they are about 60 feet from each other and not at all visible or accessible to each other.
    How are they connected? Each service, I mean.</font>
  • <font size="2" face="Verdana, Helvetica, sans-serif">We don't know the nominal voltage and phase of the system, and available utility (230.2(C)(2)).</font>
  • <font size="2" face="Verdana, Helvetica, sans-serif">We don't know if one or both of the disco's are inside or outside.</font>
<font size="2" face="Verdana, Helvetica, sans-serif">If the disco's are outside, there are no service entrance conductors, so 230.40 can suck an egg. Depending on a lot of variables, so long as 230.2(E) is satisfied, it's difficult to understand where a violation could be cited accurately with the information at hand. :)
 

pierre

Senior Member
Re: Conn. installation

*120/208 volts
*each service is 200 amps
*one service disconnect is in one space, the other disconnect is in the other space, divided by a partition that was constructed to divide one building into two spaces.
* the building is not large.
*one set of service entrance conductors serves one service, the other set of service entrance conductors goes around the outside of the building to the other side, about 60 ft.
* both service entrance conductors are terminated to the same service drop at the same location- which is above one of the services.
Actually the one service was existing, and they added the second service when the other guy rented the space.

There are no special considerations like size of service, phases, voltages, etc..


Is there anyone from Conn. who may know if there are local laws that are different than the NEC?
 
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