difference of opinion on grounding electrode

[Sparky32297]

OK, I will try and paint a picture

200 amp disconnect on out side of house with 2 ground rods going to it.

Inside there is a 200 amp panel fed with 2 hots a neutral (proper size) and a #4 copper ground wire from service disconnect.

The electrician has run #4 copper ground wire from the water pipe (within 5' of entrance to house) to the sub panel.

One inspector is of the opinion that placing the wire from the water pipe in the ECG bar is sufficient and covers the grounding requirements of the service.(The ground wire from the water pipe can be removed from the ECG bar with a screwdriver)

The other inspector thinks that the wire from the outside service and the wire from the water pipe should be joined with an irreversible connector and then take a tail from this down to the panel. This eliminates the ability to break the continuity to the service in his opinion.

Thoughts?

 

[augie47]

IMO, 250.24 requires the grounding electrode conductor to be connected to the grounded conductor at a point from the load end of the utility supply to where the grounded service conductor is connected at the SERVICE PANEL.
Furthermore 250.62(C) requires the GEC to be continuous or spliced by irreversible means.
To me the GEC should run from the outside service panel. If it has to be spliced to reach, it must be by irreversible means.
In addition, if the grounding electode conductor to the water pipe grounding electrode is routed thru a metallic nipple between the panels, that nipple would require bonding per 250.62(E)

 

[Dennis Alwon]

First off, the wire that runs to the water pipe must terminate in the service disconnect or the meter--- either way it must be before the interior panel. It appears they are trying to use the egc as the gec and I don't believe that is compliant but it would appear it should work however---read below

250.64(C) Continuous. Grounding electrode conductor(s) shall be installed in one continuous length without a splice or joint except as permitted in (1) and (2):
(1) Splicing shall be permitted only by irreversible compression-type connectors listed as grounding and bonding equipment or by the exothermic welding process.
(2) Sections of busbars shall be permitted to be connected together to form a grounding electrode conductor.

 

[mcclary's electrical]

The answer could vary, if this a double wide or modular, the service is probably outside, therefore the panel inside is in a seperate structure, therefore, if the water pipe is in contact with the earth for more than ten feet, he must use it, and it must come to his panel inside



However, if this is a normal house, and the outside service is mounted to the structure, the see above post

 

[ivsenroute]

If there are 2 ground rods outside with a GEC to the disconnect then that is the grounding electrode system.

The wire to the water pipe is only for bonding purposes, not as an electrode for the grounding system

 

[Dennis Alwon]

If there are 2 ground rods outside with a GEC to the disconnect then that is the grounding electrode system.

The wire to the water pipe is only for bonding purposes, not as an electrode for the grounding system

Sure but if the water pipe has 10 feet or more of metal in the earth than it is an electrode and is part of the GEC system

 

[ivsenroute]

Sure but if the water pipe has 10 feet or more of metal in the earth than it is an electrode and is part of the GEC system

You gonna dig it up to prove it?

Just bond it and call it a day.

 

[Volta]

You gonna dig it up to prove it?

Just bond it and call it a day.

I don't think the electrician wants to dig it up to prove that it isn't an electrode :roll:. If it is "present at" the building, both it and the rods shall be "bonded together to form the grounding electrode system" 250.50. Proven or not, if it's present, it must be bonded to the GES.

 

[mcclary's electrical]

I don't think the electrician wants to dig it up to prove that it isn't an electrode :roll:. If it is "present at" the building, both it and the rods shall be "bonded together to form the grounding electrode system" 250.50. Proven or not, if it's present, it must be bonded to the GES.

I agree, the only thing proving it would do is change the size of the bond

 

[Dennis Alwon]

I don't think the electrician wants to dig it up to prove that it isn't an electrode :roll:. If it is "present at" the building, both it and the rods shall be "bonded together to form the grounding electrode system" 250.50. Proven or not, if it's present, it must be bonded to the GES.

Thank you- at least you got my point.

 

[Dennis Alwon]

I agree, the only thing proving it would do is change the size of the bond

Huh, the bond to a metallic pipe not part of the GES (not connected to 10' of underground metallic piping) would still be based on 250.66. The wire would be the same size.

 

[mcclary's electrical]

Huh, the bond to a metallic pipe not part of the GES (not connected to 10' of underground metallic piping) would still be based on 250.66. The wire would be the same size.

Your right, I was thinking ground rods #6 water pipe #4,,,,but this is pipe either way

 

[ivsenroute]

I don't think the electrician wants to dig it up to prove that it isn't an electrode :roll:. If it is "present at" the building, both it and the rods shall be "bonded together to form the grounding electrode system" 250.50. Proven or not, if it's present, it must be bonded to the GES.

My point was to prove that it IS an electrode, not prove it IS NOT.

Since we cannot see it, we can not assume that it is, therefore bond vs making it part of the exterior GEC system.

You want to use it as part of your GEC system then prove it is 10' or more.

I am trying to make things easier and simple. No crimps, no wasted wire. Just bond the pipe.

 

[don_resqcapt19]

My point was to prove that it IS an electrode, not prove it IS NOT.
...

I look at this the other way. If you have a metal water pipe entering the building from below grade, it is a required electrode until proved otherwise. This would be based on the normal installations in my area where it would be very rare to find the metallic pipe changed to non-metallic pipe less than 10' from the building. If you are in an area where it is common to run non-metallic to a metallic stub just outside the building, then I would assume it is not an electrode. Like many things in really depends on what is common in your area.

 

[RICK NAPIER]

In NJ if we see a metal water pipe going into the ground we assume it is 10' and an electrode until proven otherwise.

 

[One-eyed Jack]

Huh, the bond to a metallic pipe not part of the GES (not connected to 10' of underground metallic piping) would still be based on 250.66. The wire would be the same size.

If you assume the water pipe is a grounding electrode 250.66 (a) allows you to use a #6 copper gec. If you assume it is not a grounding electrode it must be bonded and sized according to table 250.66 and for a 200 amp service it would be a #4.

 

[Volta]

If you assume the water pipe is a grounding electrode 250.66 (a) allows you to use a #6 copper gec. If you assume it is not a grounding electrode it must be bonded and sized according to table 250.66 and for a 200 amp service it would be a #4.

No, Sub-section (A) is only for a driven rod, driven pipe, or plate. Not for an underground metal water pipe. See 250.52(A)(6) as compared to 250.52(A)(1), they are different uses of the word "pipe".

 

[augie47]

No, Sub-section (A) is only for a driven rod, driven pipe, or plate. Not for an underground metal water pipe. See 250.52(A)(6) as compared to 250.52(A)(1), they are different uses of the word "pipe".

AGREE !

but have you ever understood why 250.104 (A) requires a 250.66 sizing when you are only bonding ?

 

[One-eyed Jack]

No, Sub-section (A) is only for a driven rod, driven pipe, or plate. Not for an underground metal water pipe. See 250.52(A)(6) as compared to 250.52(A)(1), they are different uses of the word "pipe".

OK I stand corrected. That being true the only difference will be the connection point to the water pipe. Within 5' or not. And people wonder why there are so many differences of opinon on what the NEC requires.

 

[augie47]

OK I stand corrected. That being true the only difference will be the connection point to the water pipe. Within 5' or not. .

Correct

And people wonder why there are so many differences of opinion on what the NEC requires.

The deeper you study the worse it gets :grin:
Thats what makes this such an interesting and challenging place.