# subpanel without neutral



## BuzzKill (Oct 27, 2008)

Sounds like 215.7 is your "out" clause to let you walk on this one however I am not 100% on this.


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## Barjack (Mar 28, 2010)

As long as the service has a grounded conductor, 200.2 is satisfied. Because you referenced 215.7, I have to ask, did you actually tap from larger conductors, or did you run a feeder from another panel? If its a feeder, 215.7 wouldn't really apply, and I would ask your inspector where the NEC requires a grounded conductor in a feeder.


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## eds (Mar 21, 2009)

Barjack said:


> As long as the service has a grounded conductor, 200.2 is satisfied. Because you referenced 215.7, I have to ask, did you actually tap from larger conductors, or did you run a feeder from another panel? If its a feeder, 215.7 wouldn't really apply, and I would ask your inspector where the NEC requires a grounded conductor in a feeder.


Feeder from another panel, inspectors contention is 200.2 requires a grounded conductor with the feeders. What type of installation fall under 215.7?


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## Barjack (Mar 28, 2010)

eds said:


> Feeder from another panel, inspectors contention is 200.2 requires a grounded conductor with the feeders. What type of installation fall under 215.7?


215.7 references tapping, which means connecting smaller conductors to larger conductors with no additional overcurrent protection. See 240.21(B). I assumed you were running a feeder from a panel, but I wanted to clarify. I guess it is still called a feeder though.


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## Magnettica (Jan 23, 2007)

Barjack said:


> As long as the service has a grounded conductor, 200.2 is satisfied. Because you referenced 215.7, I have to ask, did you actually tap from larger conductors, or did you run a feeder from another panel? If its a feeder, 215.7 wouldn't really apply, and I would ask your inspector where the NEC requires a grounded conductor in a feeder.


I think you're okay. 

250.32(B)


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## eds (Mar 21, 2009)

Magnettica said:


> I think you're okay.
> 
> 250.32(B)


 
Don't follow how this would apply


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## Barjack (Mar 28, 2010)

eds said:


> Don't follow how this would apply


I don't follow either. That references separate buildings or structures. It may be subject to interpretation, as to how you define "Premises Wiring System".



> 200.2 General. All premises wiring systems, other than
> circuits and systems exempted or prohibited by 210.10,
> 215.7, 250.21, 250.22, 250.162, 503.155, 517.63, 668.11,
> 668.21, and 690.41, Exception, shall have a grounded conductor
> ...





> Premises Wiring (System). Interior and exterior wiring,
> including power, lighting, control, and signal circuit wiring
> together with all their associated hardware, fittings, and
> wiring devices, both permanently and temporarily installed.
> ...


To me, this means that at least the starting point (service) there shall be a grounded conductor, which you most likely have. I don't see where it requires the grounded conductor to be extended any further if not necessary.


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## BuzzKill (Oct 27, 2008)

eds said:


> I have a 8 circuit subpanel installed for a geothermal system, installed a #2 se cable from service panel to subpanel without a neutral as all loads are 240v. I now need to deal with a inspector that feels that this is a violation of 200.2, I feel that 215.7 allows this install (at this point neither is ready to concede). Just wondering if there may be a code section that might help get this settled.


Now that the tap/feeder issue is resolved, I don't think you have any choice but to run a N with the feeders, regardless if it is only going to feed 220volt loads; 200.2 is pretty clear in the exceptions.


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## eds (Mar 21, 2009)

BuzzKill said:


> Now that the tap/feeder issue is resolved, I don't think you have any choice but to run a N with the feeders, regardless if it is only going to feed 220volt loads; 200.2 is pretty clear in the exceptions.


if this is the case what code sections allows me to install a 240 circuit without a neutral, such as a electric water heater or air conditioner


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## BuzzKill (Oct 27, 2008)

eds said:


> if this is the case what code sections allows me to install a 240 circuit without a neutral, such as a electric water heater or air conditioner


Those require disconnects and not sub-panels, big difference.


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## Barjack (Mar 28, 2010)

Buzzkill, could you cite the article that requires a neutral to be extended with the feeder past the service equipment or source panel if not required? Also, if there is a neutral at the service equipment, how is 200.2 not satisfied? The premises wiring system would have a grounded conductor, even if in a small capacity.


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## eds (Mar 21, 2009)

210.10 references a tap conductor with out a neutral to supply what is listed in that section. What is the difference is those tap conductors and the reference to tap conductors in 215.7.


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## Barjack (Mar 28, 2010)

eds said:


> 210.10 references a tap conductor with out a neutral to supply what is listed in that section. What is the difference is those tap conductors and the reference to tap conductors in 215.7.


210 is branch circuits, 215 is feeders. Its almost the same language.


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## eds (Mar 21, 2009)

Barjack said:


> Buzzkill, could you cite the article that requires a neutral to be extended with the feeder past the service equipment or source panel if not required? Also, if there is a neutral at the service equipment, how is 200.2 not satisfied? The premises wiring system would have a grounded conductor, even if in a small capacity.


I have also pointed out 220.61 (A), if there is no imbalance to calculate what size neutral would be required?


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## Barjack (Mar 28, 2010)

eds said:


> I have also pointed out 220.61 (A), if there is no imbalance to calculate what size neutral would be required?


Tell the inspector you will run a #14 neutral.


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## eds (Mar 21, 2009)

Barjack said:


> 210 is branch circuits, 215 is feeders. Its almost the same language.


Thats my point 210.10 allows these branch circuits to be installed without a grounded conductor. 215.7 allows a feeder without a grounded conductor. They both reference a tap conductor. I guess my question is when I pull a branch circuit to a hot water heater and install a 2 pole thirty in the panel is this the tap referenced in 210.10? Would this not be the same type of tap referenced in 215.7 for a feeder?


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## Magnettica (Jan 23, 2007)

eds said:


> Don't follow how this would apply


My bad. I just reread your original post. Thought you were referring to a detached garage. Must've been the cold medicine.


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## Barjack (Mar 28, 2010)

eds said:


> Thats my point 210.10 allows these branch circuits to be installed without a grounded conductor. 215.7 allows a feeder without a grounded conductor. They both reference a tap conductor. I guess my question is when I pull a branch circuit to a hot water heater and install a 2 pole thirty in the panel is this the tap referenced in 210.10? Would this not be the same type of tap referenced in 215.7 for a feeder?


Its close to the same thing. Taps have specific rules mainly regarding distance and wire size in relation to the size of the conductors they are tapping. When you run a feeder from a panel, it is not a tap.

IMHO, your inspector is misinterpreting the definition of "Premises Wiring System".


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## BuzzKill (Oct 27, 2008)

eds said:


> I guess my question is when I pull a branch circuit to a hot water heater and install a 2 pole thirty in the panel is this the tap referenced in 210.10?


 no


eds said:


> Would this not be the same type of tap referenced in 215.7 for a feeder?


again, no, IMO


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## eds (Mar 21, 2009)

what type of install


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## BuzzKill (Oct 27, 2008)

Barjack said:


> Buzzkill, could you cite the article that requires a neutral to be extended with the feeder past the service equipment or source panel if not required?


 I'm still think 200.2 works here, as a sub panel, IMO, is a "wiring system" and not a plain circuit.


Barjack said:


> Also, if there is a neutral at the service equipment, how is 200.2 not satisfied?


Don't believe I ever said it didn't satisfy it...he put the sub-panel in and I think it needs a N.


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## eds (Mar 21, 2009)

what type of install would 210.10 and 215.7 be refering too


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## Barjack (Mar 28, 2010)

BuzzKill said:


> he put the sub-panel in and I think it needs a N.


So what size N would be acceptable, and how would you calculate it?


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## BuzzKill (Oct 27, 2008)

eds said:


> what type of install would 210.10 and 215.7 be refering too


See, I think of taps as splices, not circuits derived from a panel-board's 2 pole breaker (as in your case), so those sections are of no relevance here, I think.


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## Magnettica (Jan 23, 2007)

eds said:


> what type of install would 210.10 and 215.7 be refering too


One refers to branch circuits, one refers feeders.


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## BuzzKill (Oct 27, 2008)

Barjack said:


> So what size N would be acceptable, and how would you calculate it?


220.61 :thumbsup:


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## eds (Mar 21, 2009)

BuzzKill said:


> 220.61 :thumbsup:


don't have a maximum unbalance to calculate


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## Barjack (Mar 28, 2010)

Great. And since all of the loads connected to the sub panel are 240V, the calculated neutral load would be 0 Amps. No neutral required.:thumbsup:


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## BuzzKill (Oct 27, 2008)

eds said:


> don't have a maximum unbalance to calculate


In that case, run the same size as your ungrounded conductors.


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## Barjack (Mar 28, 2010)

BuzzKill said:


> In that case, run the same size as your ungrounded conductors.


I'm not into wasting wire.:no:


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## BuzzKill (Oct 27, 2008)

Barjack said:


> I'm not into wasting wire.:no:


200.2 General. All premises wiring systems....shall have a grounded conductor
that is identified in accordance with 200.6. The
grounded conductor shall comply with 200.2(A) and (B). 

I think a sub panel is a "wiring system", as I mentioned before.


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## Barjack (Mar 28, 2010)

BuzzKill said:


> I think a sub panel is a "wiring system", as I mentioned before.


It is a wiring system, but only part. The entire system, the "premises wiring system", includes everything, and as long as there is a neutral at least at the beginning of the system (service equipment), 200.2 is satisfied


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## BuzzKill (Oct 27, 2008)

Barjack said:


> as long as there is a neutral at least at the beginning of the system (service equipment), 200.2 is satisfied


code reference?


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## Barjack (Mar 28, 2010)

BuzzKill said:


> code reference?


250.24(C) requires the grounded conductor be brought to the service equipment. Since the service equipment is part of the premises wiring system, 200.2 is satisfied.


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## BuzzKill (Oct 27, 2008)

Hmmm, I want more opinions on this; you have a good argument but I am not yet satisfied. Actually, in response to the OP's question, I think pulling a neutral would be good foresight on his part in case 110-N loads are needed in the future.


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## eds (Mar 21, 2009)

branch circuits are part of the premise wiring system, I don't run a grounded conductor to the hot water heater. I am still not convinced that I need to run one with a feeder


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## eds (Mar 21, 2009)

BuzzKill said:


> Hmmm, I want more opinions on this; you have a good argument but I am not yet satisfied. Actually, in response to the OP's question, I think pulling a neutral would be good foresight on his part in case 110-N loads are needed in the future.


feeder was sized for the loads served any additional loads may overload the feeder


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## BuzzKill (Oct 27, 2008)

eds said:


> feeder was sized for the loads served any additional loads may overload the feeder


what are the chances of all 8 circuits running at once?


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## Magnettica (Jan 23, 2007)

BuzzKill said:


> Hmmm, I want more opinions on this; you have a good argument but I am not yet satisfied. Actually, in response to the OP's question, I think pulling a neutral would be good foresight on his part in case 110-N loads are needed in the future.



The future wiring is an extra :thumbsup:


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## eds (Mar 21, 2009)

BuzzKill said:


> what are the chances of all 8 circuits running at once?


Acutally there is a chance both aux strips and the heat puimp portion will run at the same time


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## davey (Aug 14, 2010)

BuzzKill said:


> what are the chances of all 8 circuits running at once?


I'm not sure why you say, "What are the chances"? We all use the rules for load calculation, which have discounting for diversity an integral part. Only when we _know_ that certain loads won't run simultaneously do we drop the smaller.

Almost every time someone asks me to add another load to an old panelboard, I ownder, as the song says, "oh-ho-o-oh." A week ago I replaced two adjacent fuse boxes in an old-timer's finished basement. One was fed off the other, and they both came off a 50 amp feeder from the service at the other end of the house. They (and the one panel I used to replace them) fed an oven, a range, and 10 branch circuits. Never had tripped the feeder, the man told me. Okay, . . . I guess. But I sure would have liked to move the cooking equipment over to the main panel.


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