Service GEC

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websparky

Senior Member
Location
Cleveland, Ohio
servgrnd.jpg
 

jwelectric

Senior Member
Location
North Carolina
Re: Service GEC

Dave

I am looking at exhibit 250.27 of the 2005 handbook and it shows the grounding electrode conductor hitting the water pipe then the building steel and then the rod.

I am sure that some one is going to jump in and state that the handbook is not enforceable but I think that it shows a good example of what is stated in 250.64 (F)

250.64 (F) To Electrode(s). A grounding electrode conductor shall be permitted to be run to any convenient grounding electrode available in the grounding electrode system, or to one or more grounding electrode(s) individually, or to the aluminum or copper busbar as permitted in 250.64(C). The grounding electrode conductor shall be sized for the largest grounding electrode conductor required among all the electrodes connected to it.

There is also a good picture in the 2005 Analysis of Changes on page 97 that shows the grounding electrode conductor landing on a busbar and going to the electrodes as outlined in 250.52
:)
 

mdshunk

Senior Member
Location
Right here.
Re: Service GEC

IF the GEC went from the panel to the water pipe and ended in a clamp...

THEN the GEC started at the water pipe with another clamp and went to the ground rod...

THEN you would have a violation. The GEC to the rod would be using an inch or two of the water pipe as the grounding electrode conductor.

On the other hand...

If the GEC passed straight through one clamp at the water pipe and continued straight on to the rod, then you'd be compliant.
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
Re: Service GEC

Originally posted by mdshunk:
IF the GEC went from the panel to the water pipe and ended in a clamp...

THEN the GEC started at the water pipe with another clamp and went to the ground rod...

THEN you would have a violation. The GEC to the rod would be using an inch or two of the water pipe as the grounding electrode conductor.

On the other hand...

If the GEC passed straight through one clamp at the water pipe and continued straight on to the rod, then you'd be compliant.
The GEC only has to be continuous to one item of the GES, bonding jumpers can be used to connect all the other available parts together.

Here is a similar graphic to the handbook mentioned by JW.

1003537943_2.gif


Roger
 

dillon3c

Senior Member
Re: Service GEC

This is a Residental installation as denoted..
250.52(A)(1)
*Interior metal water piping located more than 1.52 (5ft) from point of entrance to the building shall not be used.

* Exception- would not apply being of residental installation.

This being the only problem I can see..What point does underground water pipe enter interior of Residental building/structure and distance..

Edited:Came back to add..Dave you are returning to help out with your question/answer pictorial,right.?-( was there some trick question involved .?)

[ July 03, 2005, 08:49 PM: Message edited by: dillon3c ]
 

electricmanscott

Senior Member
Location
Boston, MA
Re: Service GEC

Here is where I have a problem with this and I am not opening the book on the 4Th of July. :p If you lose your water pipe as your electrode the wire to the rod is not a bonding jumper anymore it is now the gec. So the gec would run from the panel to the water pipe, the water pipe would in effect be part of the gec, then the gec continues to the rod. (or two rods) This is three seprate peices of a gec that must be continuous. My solution is a wire from the panel to the pipe, and another wire from the panel to the rod.
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
Re: Service GEC

Scott, "what if" frogs had wings?

We could "what if" everything if we wanted to. ;)

Roger
 

electricmanscott

Senior Member
Location
Boston, MA
Re: Service GEC

Roger I am not a what if guy but flying frogs would be cool. :cool: I think the whole point of the supplemental ground rod(s) is based on "What if". So bearing that in mind it would seem to make sense that it should be installed to "what if" requirements.
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
Re: Service GEC

Originally posted by electricmanscott:
Roger I am not a what if guy but flying frogs would be cool. ;)

Roger
 

electricmanscott

Senior Member
Location
Boston, MA
Re: Service GEC

Originally posted by georgestolz:
What if in the future four inches of copper piping were used to connect two pieces of GEC? Oh, the humanity!
I don't disagree that it is no big deal but I thought the point of this forum was to argue every little nuance of the code into oblivion. :p
 

dillon3c

Senior Member
Re: Service GEC

Originally posted by macmikeman:
Posted by Dillon3c " *exeption - would not apply bieng of residential installation"

Dillon, in what part of 250.52 does it exempt residential?
250.52(A)(1)

Exception: In Industrial and Commercial buildings (or structures) where conditions of maintenace and supervison ensure that only qualified persons service the installation,intererior metal water piping located more than 1.52m (5ft.) from the point of entrance to the building shall be permitted as part of the grounding electrode system as a conductor to interconnect electrodes that are part of the grounding electrode system provided that the intire length,other than short sections passing perpendicular through wall,floors or ceilings,of the interior metal water pipe that is being used for the conductor is exposed..

[ July 04, 2005, 01:11 PM: Message edited by: dillon3c ]
 

dillon3c

Senior Member
Re: Service GEC

Now, I'm not looking a anything other than NFPA 70..I'm sure that this going to be debated.And no, this is not meaning that "qualified persons" have to be present on site 24/7.They can be on-call,or qualified contractor..We can also debate (or structures)and the meaning..

[ July 04, 2005, 01:31 PM: Message edited by: dillon3c ]
 

macmikeman

Senior Member
Re: Service GEC

Sorry Dillon, I had you backwards, I thought you were allowing the exemption for residential whereas you were actually saying residential is not allowed the exception, which is correct.
 
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