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GEC Not long enough from rebar in footer

jar546

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Here is the scenario:

* Service located during footer pour, a 1/0 cu wire properly tied to rebar in footer before the pour.
* Service location changed by owner/GC after footer pour complete.
* 1/0 wire not long enough to get to new location of the main service disco outside.

The plan is to do what is drawn in attached photo. I drew this with a mouse in Photoshop so sorry for the crappy job.

The existing 1/0 from the rebar inside the footer will be taken to a ground rod where it will pass through without splicing to another ground rod where it will be terminated on a clamp. Each ground rod will have 2 listed/labeled clamps. Where the GEC from the footer goes through the ground rod, the second clamp will then be use to connect 1/0 to the exterior 2" cu water pipe. The 2nd rod which will be closer to the main disco will use one clamp to terminate the end of the GEC coming from the concrete encased electrode and the other clamp to attach new 1/0 that will then continue on to the service disco where it will terminate at the neutral bar lug.

This is not the method I want to use, I don't believe this would be a code compliant installation since the GEC needs to be continuous and building steel is available.

For those that ask why we are using ground rods at all, I can't answer that other than they are show on the prints, otherwise not required due to the CEE.

My plan was to:

1) Irreversible crimp to join the existing 1/0 and a piece that is long enough to get to the service disco.
2) Add another irreversible crimp to add a pice of 1/0 to run over to the 2" water pipe.
3) Install the stupid, unnecessary ground rods to match the prints and have the GEC as a pass-through.
4) Terminate in the service disco as required

Is the method described first compliant in your opinion? NEC 2014 applies.

Yes, I know you will read this in the morning (you know who you are) and will talk to me about it at work.

GEC.jpg
 
Me thinks the GEC needs to be continuous to the 2 rods....No? As you only "need" one GE, and everything else is bonding for the GES, the GEC only needs to be continuous to the first GE...But I am not an electrician and I am to lazy to open to 250.whatevertheheck (.50 or .55 maybe)
 
grounding.JPG

Just was at a NEC update class run by IAEI and we had a discussion about what it means to be continuous. The instructor which is a NEC writer said continuous does't mean it has to be one wire. He showed use a slide that showed two acorns on a rod with separate ground wires it and this would be considered continuous.

In the picture of a grounding electrode system from the 2014 NEC Handbook the water pipe and the steel column is used as part of the continuous system.
 
250.66(C) Note that the GEC will land on a water pipe, building steel or a ufer and then a jumper to other electrodes is allowed. In other words the GEC can't hit a rod first and splice from there.....unless of course the rod is the only electrode available as in no water metal pipe in the ground, no building steel, and no ufer.
 
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250.64 (F) (1) Tne grounding electrode conductor shall be permitted to be run to any convenient grounding electrode available in the grounding electrode system where other electrode(s) if any, is connected by bonding jumpers that are installed in accordance with 250.53(C).
 
250.30 (A)(4) Grounding Electrode. The grounding electrode shall be as near as practicable to, and preferably in the same area as, the grounding electrode conductor connection to the system. The grounding electrode shall be the nearest of one of the following
  1. (1) Metal water pipe grounding electrode as specified in 250.52(A)(1)
  2. (2) Structural metal grounding electrode as specified in 250.52(A)(2)

Exception No. 1: Any of the other electrodes identified in 250.52(A) shall be used if the electrodes specified by 250.30(A)(4) are not available.

Exception No. 2 to (1) and (2): If a separately derived system originates in listed equipment suitable for use as service equipment, the grounding electrode used for the service or feeder equipment shall be permitted as the grounding electrode for the separately derived system.

Informational Note No. 1: See 250.104(D) for bonding requirements for interior metal water piping in the area served by separately derived systems.

Informational Note No. 2: See 250.50 and 250.58 for requirements for bonding all electrodes together if located at the same building or structure.

250.68(C) Grounding Electrode Connections. Grounding electrode conductors and bonding jumpers shall be permitted to be connected at the following locations and used to extend the connection to an electrode(s):
(1) Interior metal water piping located not more than 1.52 m (5 ft) from the point of entrance to the building shall be permitted to be used as a conductor to interconnect electrodes that are part of the grounding electrode system.
Exception: In industrial, commercial, and institutional buildings or structures, if conditions of maintenance and supervision ensure that only qualified persons service the installation, interior metal water piping located more than 1.52 m (5 ft) from the point of entrance to the building shall be permitted as a bonding conductor to interconnect electrodes that are part of the grounding electrode system, or as a grounding electrode conductor, if the entire length, other than short sections passing perpendicularly through walls, floors, or ceilings, of the interior metal water pipe that is being used for the conductor is exposed.


Rick,
I tried to include the rest of 250.68(C) but the cut and paste quit working......I just don’t want to argue the point....so I’m out of here.
 
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