# Grounding sub panel



## erics37 (May 7, 2009)

Toto said:


> I live in an area where many properties have out buildings and detached garages, shops, etc. Often times we install sub panels a few hundred feet from the service panel to feed these buildings. For years inspectors have required different grounding methods depending on their personal preference. Electricians handle grounding varyingly. Some electricians do not run a ground to the sub panels and just pound ground rods. Some electricians run ground wires to feed sub panels and do not pound ground rods. Some electricians run ground wires and pound ground rods. The current inspector states separate building=separate ground systems=separate ground rods and no ground wire from main service. Everyone feels differently and I noticed the discussion about the un-grounded panel earlier touching on this.


If it's new construction, your inspector needs to get his act together and get a 2011 code. Unless there's a local amendment (I doubt it) then a detached building supplied by a feeder needs to have its own equipment grounding conductor IN ADDITION to a grounding electrode system installed at the building in question. The grounding electrode system would be bonded to the EGC.

And I don't know what kind of continuing education requirements are reguired for licensing/certification in California, but you and your fellow electricians should go to a class on Grounding & Bonding.

Tell your inspector to read 250.32 in its entirety. It's spelled out clear as day.


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## Hotlegs (Oct 9, 2011)

Toto said:


> The current inspector states separate building=separate ground systems=separate ground rods and no ground wire from main service. Everyone feels differently and I noticed the discussion about the un-grounded panel earlier touching on this.


it's still one service no matter how many buildings and sub panels that 1 service feeds. So it needs a ground wire to each sub panel and each buildings grounds tie back to the main service.


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## RePhase277 (Feb 5, 2008)

erics37 said:


> If it's new construction, your inspector needs to get his act together and get a 2011 code. Unless there's a local amendment (I doubt it) then a detached building supplied by a feeder needs to have its own equipment grounding conductor IN ADDITION to a grounding electrode system installed at the building in question. The grounding electrode system would be bonded to the EGC.
> 
> And I don't know what kind of continuing education requirements are reguired for licensing/certification in California, but you and your fellow electricians should go to a class on Grounding & Bonding.
> 
> Tell your inspector to read 250.32 in its entirety. It's spelled out clear as day.


It really is clear as day when you take the time to read it.


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## kennydmeek (Sep 12, 2009)

4 wire has to go back to the main panel in my world. If you derive a ground separately without bonding the neutral bar to the can the ground will float as well..not legal to bond neutral bars to ground in sub panels here.


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## Toto (Jul 27, 2011)

kennydmeek said:


> 4 wire has to go back to the main panel in my world. If you derive a ground separately without bonding the neutral bar to the can the ground will float as well..not legal to bond neutral bars to ground in sub panels here.


Everyone treats sub panels as sub panels when they are under the same roof. But, I started to notice systems without ground wires when the sub panel was for a separate building. My understanding was always the same as everyone's here. What difference would separate roofs make? But, when I brought it up with the inspector he pulled out some engineering paper and told me I did not have to bring ground wire to sub panels in separate buildings. I was amazed to say the least. Which is why I brought it up here.

His papers he showed me had the grounds and neutrals bonded in separate buildings at the sub panels. So it looked like each building was it's own ground system.
I have never thought this was code but if an inspector is arguing it...


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## ausha (Mar 21, 2011)

With all the grow opps. out in Ca. Your inspectors really need to learn the Code. Just currious what municipality is he representing?


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## Toto (Jul 27, 2011)

He knows code extremely well. Also enforces it with a passion. Which is why I'm out here fishing for an explanation.


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## Electron_Sam78 (Feb 26, 2010)

as erics37 stated section 250.32 is in direct conflict with your inspector's paperwork. Prior to the 2008 code cycle that would have been perfectly code compliant but since the 2008 cycle each separate building or structure must have an EGC and must have a grounding electrode system which could be as simple as a concrete encased electrode in the form of bonded reinforcing steel in the foundation of the building or driven rods.


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## RePhase277 (Feb 5, 2008)

Then he is inspecting to a version of the code before the 2008 edition. In, say 1975, it was legal to run a 3-wire feed to a remote building and bond the neutral same as a service, so long as no other continuous metallic paths existed between the two buildings.

In 2008 that changed. Now it is required that all subfeeds have a bonding conductor in them.


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## di11igaf (Jan 1, 2012)

If you don't have an egc to the sub from the main, you now have no path back to mbj, how would ocpd open during ground fault?


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## RePhase277 (Feb 5, 2008)

di11igaf said:


> If you don't have an egc to the sub from the main, you now have no path back to mbj, how would ocpd open during ground fault?


By bonding the neutral at the sub.


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## BBQ (Nov 16, 2010)

You can still go without an EGC if you treat it like a service by tapping it ahead of the homes service disconnect.


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## CraigV (May 12, 2011)

Bottom line is that if this AHJ thinks he's a code expert, he needs to tell you what code cycle he's enforcing, and whether it is amended. Without this you've got no way to know how to proceed, and can't dispute his opinion.


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## CraigV (May 12, 2011)

di11igaf said:


> If you don't have an egc to the sub from the main, you now have no path back to mbj, how would ocpd open during ground fault?





InPhase277 said:


> By bonding the neutral at the sub.


Can you post the article and code cycle?


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## sullivanth (Feb 23, 2013)

CraigV said:


> Can you post the article and code cycle?


Take a look at 250.32 in the 2011 NEC.


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## Toto (Jul 27, 2011)

For the most part they enforce 2008 and some 2011 if it's a safety issue. I know they want ground wires ran for sub panels in a house, and I've always wired with ground wires to a sub panel no matter where it is. I can't remember ever thinking it was okay--but I'm younger than some. So he knows the code but is okaying contractors to violate it in certain circumstances. Anyway next time I see him I'll try to get a copy of his fancy theory and post it. I think this inspector actually has electrical engineering experience. Since the rest of the world thinks this idea is crazy I think I'll continue to run grounds from main panel like usual. Thanks,


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## Celtic (Nov 19, 2007)

InPhase277 said:


> It really is clear as day when you take the time to read it.



...and if you are dealing with an illiterate ~ a picture!


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## Toto (Jul 27, 2011)

By the way: I'm not arguing the code. I know the code and I have always ran grounds to sub panels. I'm just seeing if people in other areas have heard this from code enforcement ever...and apparently they haven't.


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## di11igaf (Jan 1, 2012)

InPhase277 said:


> By bonding the neutral at the sub.


Since when is that legal :whistling2: ?
250.32B(1)


> Any installed grounded conductor shall not be connected to the equipment grounding conductor or to the grounding electrode(s)


(not talking about the exceptions for older compliant installs, but even then there is requirements)
New install- an egc is absolutely required AND necessary.(this is not directed to you inphase)


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## 3xdad (Jan 25, 2011)

Did this inspector used to run a farm?


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## BBQ (Nov 16, 2010)

InPhase277 said:


> By bonding the neutral at the sub.





di11igaf said:


> Since when is that legal :whistling2: ?


It was legal since forever and up until the 2008 NEC for separate buildings or structures.

It is still legal for existing installations in separate buildings or structures.


Here is the code section from 2005 allowing it.



> *250.32 Buildings or Structures Supplied by Feeder(s) or
> Branch Circuit(s).
> 
> (B) Grounded Systems.* For a grounded system at the
> ...


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## erics37 (May 7, 2009)

Toto said:


> Everyone treats sub panels as sub panels when they are under the same roof. But, I started to notice systems without ground wires when the sub panel was for a separate building. My understanding was always the same as everyone's here. What difference would separate roofs make? But, when I brought it up with the inspector he pulled out some engineering paper and told me I did not have to bring ground wire to sub panels in separate buildings. I was amazed to say the least. Which is why I brought it up here.
> 
> His papers he showed me had the grounds and neutrals bonded in separate buildings at the sub panels. So it looked like each building was it's own ground system.
> I have never thought this was code but if an inspector is arguing it...


Next time you see your inspector, ask him about this topic again and read through 250.32 with him. It's irrefutable.



Toto said:


> He knows code extremely well.


Apparently he doesn't.



Toto said:


> For the most part they enforce 2008 and some 2011 if it's a safety issue.


WTF :blink: So what version of the code is actually adopted as law down there? The 2008 or the 2011? The inspector's job is to enforce code as law, he can't just make s**t up and pick and choose which code to enforce.


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## Toto (Jul 27, 2011)

Yeah, that's how I'll get on his good side. Break out the code book and question him. Actually, it wouldn't be the first time.


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## erics37 (May 7, 2009)

Toto said:


> Yeah, that's how I'll get on his good side. Break out the code book and question him. Actually, it wouldn't be the first time.


If he was passing stuff that is not code compliant, or NOT passing stuff that IS code compliant, I wouldn't hesitate to get on his case about it. It's hard to pass judgement from one internet thread but he sounds like the kind of guy that's over-confident and under-competent.


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## Toto (Jul 27, 2011)

Honestly that's a pretty good description of him. Pretty arrogant. I wonder if he just makes his own rules. Especially if no one has ever heard of this.


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## di11igaf (Jan 1, 2012)

BBQ said:


> It was legal since forever and up until the 2008 NEC for separate buildings or structures.
> 
> It is still legal for existing installations in separate buildings or structures.
> 
> ...


I get that, and pointed out its still legal for existing compliant installs, I was just pointing out its not legal now.


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## CraigV (May 12, 2011)

Toto said:


> For the most part they enforce 2008 and some 2011 if it's a safety issue. I know they want ground wires ran for sub panels in a house, and I've always wired with ground wires to a sub panel no matter where it is. I can't remember ever thinking it was okay--but I'm younger than some. So he knows the code but is okaying contractors to violate it in certain circumstances. Anyway next time I see him I'll try to get a copy of his fancy theory and post it. I think this inspector actually has electrical engineering experience. Since the rest of the world thinks this idea is crazy I think I'll continue to run grounds from main panel like usual. Thanks,


Somewhere in this AHJ there is a law that clearly states the model code in force, and any amendments to it. If you show up at the local office they should be able to cite the law, and inform you of the code model. 

What you seem to be telling us is that the inspector is cherry-picking code articles to suit his whim. That might be in compliance with the code law in effect there, but I truly doubt it. The code should be easily found to refer to, not a game of "shoot the moving target", which is what you seem to be forced to deal with.


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## John Valdes (May 17, 2007)

BBQ said:


> You can still go without an EGC if you treat it like a service by tapping it ahead of the homes service disconnect.


Do you think the OP might have service extensions and feeders mixed up?
Maybe its not the inspector at all. Maybe its the OP that does not distinguish the difference between the two?


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