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#176741 - 04/10/08 02:25 PM 230.70 / 230.90  
BPHgravity  Offline
Member
Joined: Apr 2003
Posts: 139
Port Charlotte, Florida
For the follwing scenerio, are the requirements of 230.70 and 230.90 being statisfied?

240V, 3-wire, single-phase service. From the meter socket enclosure, two ungrounded conductors and one grounded conductor are brought to a 60A rated 2-pole main lug panelboard. There, one single pole 15A breaker is installed to supply a single piece of equipment. No breaker is installed on the other leg.

In addition to this arrangement, the panelboard is marked with the following label:

This panel is suitable for use as service equipment when a main breaker is installed or when not more than two branch circuit breakers are installed and is not used as a lighting and appliance panelboard.

Thanks.


Bryan P. Holland, ECO.
Secretary - IAEI Florida Chapter

2017 / 2014 NEC & Related Books and Study Guides

#176743 - 04/10/08 04:14 PM Re: 230.70 / 230.90 [Re: BPHgravity]  
George Little  Offline
Member
Joined: Jan 2004
Posts: 1,489
Michigan USA
Bryan- I think that what you are describing could very easily be a Lighting and Appliance branch circuit panel board per 408.34 and if that's correct then there is a violation.


George Little

#176753 - 04/10/08 08:59 PM Re: 230.70 / 230.90 [Re: George Little]  
sparkyinak  Offline
Member
Joined: Jul 2007
Posts: 1,327
Alaska
I'm carious, can you explain your answer George?


"Live Awesome!" - Kevin Carosa

#176761 - 04/10/08 11:08 PM Re: 230.70 / 230.90 [Re: sparkyinak]  
George Little  Offline
Member
Joined: Jan 2004
Posts: 1,489
Michigan USA
Well- Is it a Service disconnect? No because it doesn't contain the ability to disconnect the Service conductors. It is not a power panel due to the definition of a power panel found in 408.34 but it might be a Lighting and Appliance branch circuit panel board based on the same article. either way it is a code violation. Kinda a weird installation.

There is an outside chance that it might qualify for a single circuit Service Disconnect per 230.79 but we should have more information, particularly about the service conductors and their sizing.


George Little

#176764 - 04/11/08 12:53 AM Re: 230.70 / 230.90 [Re: George Little]  
sparkyinak  Offline
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Joined: Jul 2007
Posts: 1,327
Alaska
Geroge

Thanx for the explanation. I just could not wrap my noodle around your post.

Byran

Without further info, I would say you are good providing the breaker is sucured in place (408.36)(F). A single breaker can be used as a disconnect. 230.79(A). The problem is the second slot can not be use 230.79(B) unless a minimum breaker of 2 pole 30 amp breaker is used and a panel was installed.

If the disconnect is powering 1 circuit then it just passes muster. Future needs can be a little more of a problem however if there is no need for future addition then you got an economical service.


"Live Awesome!" - Kevin Carosa

#176767 - 04/11/08 08:35 AM Re: 230.70 / 230.90 [Re: sparkyinak]  
BPHgravity  Offline
Member
Joined: Apr 2003
Posts: 139
Port Charlotte, Florida
Thanks for the comments.

The breaker is is not being backfed so 408.36(F) wouldn't apply.

I know all service conductors require a disconnecting means and all service conductors require overload protection.

However in this case, there are no loads that will overload the unused leg and there is nothing actually being disconnected even with a breaker installed on that unused pole.

The code permits an MLO to be used as service equipment under certain conditions. I just not sure what the correct solution for this scenerio is.


Bryan P. Holland, ECO.
Secretary - IAEI Florida Chapter

#176768 - 04/11/08 09:31 AM Re: 230.70 / 230.90 [Re: BPHgravity]  
WESTUPLACE  Offline
Member
Joined: Mar 2004
Posts: 251
Kingwood, TX USA
The service described is very common, most traffic lights & cable TV system power supplies use a service like this. Although many only have 1 leg (120v only), quite a few are pulled with both legs to the breaker box, usually a main lug panel with 1 15 to 30 amp breaker.


#176769 - 04/11/08 11:25 AM Re: 230.70 / 230.90 [Re: WESTUPLACE]  
BPHgravity  Offline
Member
Joined: Apr 2003
Posts: 139
Port Charlotte, Florida
This is exactly what my question is refering to, a TV cable pedestal.

With the second leg brought to the service, does it not require a disconnecting means and overload device.


Bryan P. Holland, ECO.
Secretary - IAEI Florida Chapter

#176770 - 04/11/08 12:17 PM Re: 230.70 / 230.90 [Re: BPHgravity]  
sparkyinak  Offline
Member
Joined: Jul 2007
Posts: 1,327
Alaska
Originally Posted by BPHgravity

With the second leg brought to the service, does it not require a disconnecting means and overload device.


If the other slot is blocked out and the other leg is not going to be used, why waste the money? It would serve no purpose what so ever. If the 240 were needed in the future, that the existing breaker would have to go bye-bye any ways. The problem with code inforcement is understanding the intent of the code. If just the word of the code was enforced then everyone would be doing it. This what drives me bonkers with home inspectors. Unless they had real life skills, there are only book smart at best which is not a good thing in the trade. (I'm getting off my soap box). When rather I am wearing my inspector cap or pulling wire, I go with the intent of the applicable codes.


"Live Awesome!" - Kevin Carosa

#176773 - 04/11/08 04:55 PM Re: 230.70 / 230.90 [Re: sparkyinak]  
BPHgravity  Offline
Member
Joined: Apr 2003
Posts: 139
Port Charlotte, Florida
I understand the intent, but intent is not enforceable.

So, it goes back to the true point of the original question.

Where does the code permit the disconnecting means and overload protection of a service conductor to be eliminated simply because the conductor is not being used at the time of installation?


Bryan P. Holland, ECO.
Secretary - IAEI Florida Chapter

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