service disconnect

[jemsvcs]

Was recently asked to take a look at a meter socket and load center that had been disconnected from service approximately two years ago. The reason was to see if things were in order to reconnect service to the equipment. The meter and load center were installed solely to serve two light fixtures at a driveway entrance that was some distance from the residence.

The load center, a Homeline HOM24L70RB, is connected to a Landis & Gyr meter socket. The load center only has one 15A breaker for the lighting circuit.

My question is this: What about the Art. 230, Part VI and 408.16 requirements for a service disconnecting means (which is nowhere to be found in this installation)? Is there some exception that I am unaware of that allows this omission in this instance or was this 'overlooked' by the inspector or possible never even done under a permit in the first place?

 

[david]

Re: service disconnect

In this situation you know this is not technically code compliant. Since 408.16 exc. # 2 says an existing panel used as service equipment in supplying an individual residential occupancy.

You could make the determination that this panel is supplying a structure associated with an individual residential occupancy. It seems from your description this load center will never supply any additional loads than what the installer intended.

You are well within your rights to ask that they provide a main in this panel.


eddited to change the exc.# from 3 to 2

[ December 01, 2003, 01:58 PM: Message edited by: david ]

 

[don_resqcapt19]

Re: service disconnect

A main is also required by 408.16(A) to provide overcurrent protection for the panel itself.
Don

 

[inspector 102]

Re: service disconnect

It sounds to me that the service panels has a main disconnect that is rated at 15 amps. The disconnect shuts off all the power to all conductors from the service entrance conductors. Since there is less than 6 switches in the enclosures, the grouping of disconnects has also been met. Am I way off base on the question asked?

 

[don_resqcapt19]

Re: service disconnect

Inspector,
The 15 amp breaker does not disconnet the panel or provide the required overcurrent protection for the panel.
Don

 

[donnie]

Re: service disconnect

Inspector 102, I agree with you, and the installer has also met art. 230.79 (A).

From my understanding of what is being said,
as long as the panel is listed for use as
service equipment. Then I would have no doubts
about passing this installation.

 

[jemsvcs]

Re: service disconnect

Inspector,

The 15A breaker is for the lighting branch circuit and would not act as a service disconnect because it is only conducting power from one of the two ungrounded conductors.

Jemsvcs

 

[jemsvcs]

Re: service disconnect

donnie,

To meet the requirements of 230.79(A) wouldn't the 15A breaker referred to in that section have to disconnect all ungrounded conductors as required by 230.74?

Maybe I didn't make it totally clear before, but the 15A breaker in this installation only disconnects and provides overcurrent protection for one of the two ungrounded conductors of the 3-wire service. Hence, my original question as to why this was allowed the first time around without a main breaker/service disconnect in the load center.

 

[david]

Re: service disconnect

Jemsvcs

I think the requirements 230.70 are being met. What conductors serving this structure are not being disconnected from the service conductors?

I think the issue of code compliance is weather or not the breaker is providing the disconnect to the panel and is this breaker providing over-current protection for the panel.

 

[hurk27]

Re: service disconnect

Wow I have always thought that if a panel is service rated and has 6 breakers or less there was no requirement for a disconect or overcurrent protection. 230.71 (A) even mentions this arangement when it says 6 breakers in one enclosure or switchboard. But when I read 230.72 the FPN even refers to 408.16(A). And after reading 230.90(A) exception 3 seems to allow this but only if this service was only a 120 volt service not a 240 3-wire service (240v 3-wire would require two or more breakers). But it still does not mention anything about weather or not the service panel would be considered protected. I have seen many small apartments wired just like this. and I have done many sign services with only the two breakers that fed the sign with no main in the panel. Although this service is totally outside and has no possability of causing a fire to a structure it seems that it is not allowed. which makes me wonder why? when we can run unprotected service wires on the surface of a structure and even down through the outside wall in Ca. Knowing if they ever short out for what ever reason a fire will most likely happen. I don't see the logic behind some codes. If the other phase is not being used what harm will it be sitting there in this panel? and if it will be used I sure there will be a breaker installed. The other question is why would we need to protect the panel when they manufacture the same setup in a all in one combo meter panel with out a main which acording to the NEC would not be allowed because the panel part of it would not have over current protection. Look at trailer park combo meter panels they have two two-pole breaker and one or two single pole breaker all with out a main. Ok it is safe for a trailer (which have many fires) but not for an isolated service away from any buildings. I'm starting to get what Bennie see's sometimes. No rhyme or reasone. How many temporay power poles have we set with only one or two single pole breakers feeding one or two GFCI receptacles?

 

[jwh123]

Re: service disconnect

Perhaps a silly answer, but if you're concerned about the other leg of the panel, is it possible to disconnect and remove one of the ungrounded conductors from the meter to the panel, so you only have 120V available, on one side of the panel?

 

[donnie]

Re: service disconnect

jemsvcs,
From my original reply.

From my understanding of what is being said,
as long as the panel is listed for use as
service equipment. Then I would have no doubts
about passing this installation.

Art. 230.71 (A), says I can have up to 6 switches
in a single enclosure for use as service disconnecting means.
This being said, without a main being ahead of them.

 

[don_resqcapt19]

Re: service disconnect

Donnie,
The use of 230.71(A) is fine if you have a "power panelboard", but in this case we have a lighting and appliance branch circuit panelboard and it must have overcurrent protection on the line side of the panel. The FPN after 230.71(A) even refers you to the code section that requires lighting and applicance branch circuit panelboards to have overcurrent protection on the line side. See 408.16(A).
Don

 

[jim dungar]

Re: service disconnect

First, the panelboard in question is UL Listed as Service Entrance Equipment.

Second, in this situation the bus bars are not acting like a panelboard, they are really nothing more than a breaker mounting base.

Don, based on your reasoning, when could you ever use a "plug-in" style main device. Examples of which include the above mention combination service entrance devices as well as circuit breaker enclosures like the Square D QO2100BNS or their QOM22225NRB

 

[don_resqcapt19]

Re: service disconnect

Jim,
A "plug-in" main is fine as long as it is "back fed". It will provide the required protection for the panelboard and is on the "supply side" of the panel. The problem in this case is that the service panel is a "lighting and appliance branch circuit panelboard" and it must be protected. If this was a "power panelboard" then overcurrent protection for the panel is not always required. Both of the SquareD part numbers that you gave would be power panelboards as long as the breaker size is greater than 30 amps.
Don

 

[david]

Re: service disconnect

408.16 Overcurrent Protection.
(A) Lighting and Appliance Branch-Circuit Panelboard Individually Protected. Each lighting and appliance branch-circuit panelboard shall be individually protected on the supply side by not more than two main circuit breakers or two sets of fuses having a combined rating not greater than that of the panelboard.

Exception No. 2: For existing installations, individual protection for lighting and appliance branch-circuit panelboards shall not be required where such panelboards are used as service equipment in supplying an individual residential occupancy.

Exc. No2 Clearly says a lighting and appliance branch ?circuit panel board with out individual protection, can only be used for service equipment in existing individual residential occupancies.

The handbook goes on to explain that the intent is not to make a person upgrade a split bus panel if you add an additional circuit to a split bus panel. It does however say a split bus panel cannot be used in a new service . The reason is it does not provide individual protection for the panel


Individual protection being defined as no more that two over current devices protecting the panel.

Those of you who do not agree read 408.16 and tell me how you can be said it is not saying that.

You can still use the type of service equipment in a garage when the feeder is being protected according to exc. # 1

You can also group up to six throws of the hand in individual enclosures for any service.
You can use this type of service equipment when the panel meets the definition of a power panel but not when it meets the definition of a lighting and appliance branch circuit panel board.

[ December 02, 2003, 07:36 PM: Message edited by: david ]

 

[rb]

Re: service disconnect

A main lug panel is conditionally listed as suitable for use as service equipment when no more than six disconnects are provided and when not used as a lighting and appliance branch circuit panelboard. Even when used on a 120 volt service the 15 amp circuit breaker would not be permitted as a service disconnecting means because by definition the panel would now be a lighting and appliance panelboard. This would violate the listing of the panel and therefore violate 110.3(b).

Check the information provided on the panel door.

Ron Bethea

[ December 02, 2003, 08:11 PM: Message edited by: rb ]

 

[donnie]

Re: service disconnect

Don, Member #4,

230.79(A),For installations to supply only limited loads of a single branch circuit, the disconnecting means shall have a rating of not less than 15 amps.
Question, Now how many times have we seen this installation on traffic signal, services.
Traffic signals are also lights, so does that make the panel board a lighting and appliance panel board, and then would it require a main ahead of the branch circuit.

Donnie

 

[jim dungar]

Re: service disconnect

Don, I was not referring to back-fed main breakers. I was discussing enclosures with 2 pole bus bar assemblies that accept plug-on style breakers.

I do not believe that the device in question could be considered a lighting and appliance panelboard. This 2 pole device is UL listed as service entrance equipment, therefore any breaker installed must be considered as a service entrance disconnect (a main breaker). There is no room for any branch circuit to be added, so this specific application is no different than the use of a 2 pole fused disconnect switch.

 

[don_resqcapt19]

Re: service disconnect

Donnie,
As long as the service conductor is landed to the breaker, there is no code issue with panel board protection. There in not a similar rule for using a fused disconenct as the service equipment.

Jim,
If the service conductors land on a bus terminal and the breaker is rated 30 amps or less, I would say the installation is in violation of 408.16.

Don