gec in sub panel

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romeo

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Sorry but this may be a long one. A 2 meter service upgrade. It has a metal underground water pipe. It has the sevice disconnects outside the house.
The electrician runs a gec from the water pipe to a ground bar in the first panel then to the ground bar in the second panel, to 2 ground rods outside.

I red tag because the gec connection is on the load side of the main disconnect, and the neutral is really not grounded.

Now here is the question. If the gec is removed from the ground rods and terminated in the main disconnect and the 2 groundrods are also terminated there, is the insallation code compliant?

250.62 (c) (3) seems to permit the gec to be connected to the ground bar.
The only thing that bothers me is that the egc and gec from the ser feeding the panels are in parallel. But there is no neutral to case connection made other than at the line side of the main disconnect. I asked the electrician why he did it that way. He said it was so there would still be a ground to the branch circuits if the egc failed. P.S the neutral and ground are isolated at the panels
 
romeo,

I don't know exactly what the answer is but I get inspectors making me do some seemingly nutty things when two panels, subpanels or meters come into play. I've had the same inspector require completely different things at different locations.

Man I just go with the flow anymore.
 
gec in sub panel

Paul B said:
romeo,

I don't know exactly what the answer is but I get inspectors making me do some seemingly nutty things when two panels, subpanels or meters come into play. I've had the same inspector require completely different things at different locations.

Man I just go with the flow anymore.
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Paul thank you for the reply. Just to let you know I am the inspector. The way to ground this sytem is to tie the underground water pipe and the 2 ground rods together and to terminate the gec on the neutral of the main disconnect. With the gec being in one peice.

I really question why the electrician did it the way he did. He really was off base when he didn't terminate at the main. I am just trying to find a code compliant way to correct it without making him change the whole gec system. It is a long way from the water pipe to the mains.
 
Romeo, your description of the installation is a bit vague.
This is what I think you are describing
1- service main disconnect is outside with two ground ronds driven and GEC to main service disconnect.
2- water bond taken to respective sub-panel
3- is this what you are seeing
4- is this a multi-occupancy building 250.104
5-is the water pipe considered GE or just metal water piping system
 
gec in sub panel

Bea said:
Romeo, your description of the installation is a bit vague.
This is what I think you are describing
1- service main disconnect is outside with two ground ronds driven and GEC to main service disconnect.
2- water bond taken to respective sub-panel
3- is this what you are seeing
4- is this a multi-occupancy building 250.104
5-is the water pipe considered GE or just metal water piping system
Click to expand...

1- it is not like that but I want it changed to be like that.
2- no it is not the water bond it is the main gec
4- yes but the basement is not devided
5- the water pipe is the main ge
The gec extends from the main underground copper water pipe to a ground bar in each of 2 panels then to 2 ground rods outside,where the 2 service disconnects are.

I red taged because the gec is not on the line side of the main disconnect and the neutral is not grounded.

My question is if the gec from the water main and also the gec from the ground rods are changed to terminate on the neutral of the main disconnect is it code compliant,with the gec being broken at each ground bar of the sub panels.

250.64(c) it must not be spliced,with some exceptions,one being that it can be terminated to a busbar no smaller than 1/4 x 2 in. I don't believe that a ground bar meets that requirement.

Thanks for the reply
 
romeo said:
1- it is not like that but I want it changed to be like that.
2- no it is not the water bond it is the main gec
4- yes but the basement is not devided
5- the water pipe is the main ge
The gec extends from the main underground copper water pipe to a ground bar in each of 2 panels then to 2 ground rods outside,where the 2 service disconnects are.

I red taged because the gec is not on the line side of the main disconnect and the neutral is not grounded.

My question is if the gec from the water main and also the gec from the ground rods are changed to terminate on the neutral of the main disconnect is it code compliant,with the gec being broken at each ground bar of the sub panels.

250.64(c) it must not be spliced,with some exceptions,one being that it can be terminated to a busbar no smaller than 1/4 x 2 in. I don't believe that a ground bar meets that requirement.

Thanks for the reply
Click to expand...

I do not believe that the GEC to the water line can be broken as you decribe at each of the EG bars of the sub panels and the installation be Code compliant.

The typical EG bar of 3/8 x3/8 x 6" would not meet 250.64(c)(2) or(3).
 
Is the GEC between ground rods and water pipe sized for the service if so then they could run an GEC of proper size from ground rods to main service disconnects and that would connect the water pipe GE to the main service disconnects if bonding jumpers are sized properly
 
Sounds like this is an older "duplex" style home (common in our area) where one person lives in each side, but the basement is not divided. (Not legal now without proper fire separation, but existing).

If that's the case and service disconnects are outside as in OP, then the GEC must terminate outside at the main, not in the subpanels. 250.24(A)1.

And as Bea said, they could run GEC from main to ground rods. And then from ground rods to water pipe, provided that the GEC running from main to ground rod is sized properly. The conductor in this case running from the rod to the water pipe is a bonding jumper, not a GEC, so it would not need to be continuous from the panel.

John
 
gec in sub panel

j_erickson said:
Sounds like this is an older "duplex" style home (common in our area) where one person lives in each side, but the basement is not divided. (Not legal now without proper fire separation, but existing).

If that's the case and service disconnects are outside as in OP, then the GEC must terminate outside at the main, not in the subpanels. 250.24(A)1.

And as Bea said, they could run GEC from main to ground rods. And then from ground rods to water pipe, provided that the GEC running from main to ground rod is sized properly. The conductor in this case running from the rod to the water pipe is a bonding jumper, not a GEC, so it would not need to be continuous from the panel.

John
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John ,Thanks for the reply. I am confused, isin't the metal underground water pipe the main grounding elctrode,and the ground rods the required supplemental electrodes?

If I am correct 250.62 (c) would require the gec be continuous from the water pipe to the main disconnect. The gec would not be required to be unbroken from the ground rods. 250.

Thanks again I am hoping for more replys

Happy New Year to all
 
romeo said:
John ,Thanks for the reply. I am confused, isin't the metal underground water pipe the main grounding elctrode,and the ground rods the required supplemental electrodes?
Click to expand...
The water pipe is required to be supplemented by 250.53(D)(2), correct. But there is no reason that the ground rod cannot be the first electrode in the chain. First or last, the electrodes are connected and .53(D)(2) is satisfied.

250.64(F) allows us to connect a GEC to any convenient electrode. Therefore, if this were a 100A service, a #6 could be run to the ground rod, clamped and end. Then a "bonding jumper" (250.53(C)) could be pulled, connected to a second clamp on the ground rod, and connected to the water pipe.

The GEC is required to be continuous, but the bonding jumpers only have to comply with 250.64(A)(B) and (E), per 250.53(C).

Edit to add:
If it is a 200A service, be aware that 250.64(F) would require that the conductor going to the ground rod, and the conductor going to the water pipe, be sized according to the water pipe's requirement. So a #4 would be brought to the ground rod, and the bonding jumper would also be a #4. If a second ground rod is driven for 250.56, then the bonding jumper connecting that rod to the first rod could be a #6.
 
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Well done Gerorge. I agree completely.

There is a lot of confusion on this. Recently I was having a discussion with my father on this.

A few months ago I did a service with a CEE. I installed a #4 to the rebar and left about 25' to go to the panel. Well service ended up in a different location than originally planned. I said to the builder no problem, I'll just cadweld. When I did the service, I realized I could just bring #4 to the incoming copper water pipe. (which was "on the way" to the panel.) And then bring a #4 to the panel also from the water pipe. When it was inspected the inspector told my man on site to "make sure you cad weld the 2 conductors together and I'll see it on the finish." I told my man that we do not need to do that. We may, since we have a cad weld and it won't hurt. But that inspector didn't fully understand either.
 
gec in sub panel

georgestolz said:
The water pipe is required to be supplemented by 250.53(D)(2), correct. But there is no reason that the ground rod cannot be the first electrode in the chain. First or last, the electrodes are connected and .53(D)(2) is satisfied.

250.64(F) allows us to connect a GEC to any convenient electrode. Therefore, if this were a 100A service, a #6 could be run to the ground rod, clamped and end. Then a "bonding jumper" (250.53(C)) could be pulled, connected to a second clamp on the ground rod, and connected to the water pipe.

The GEC is required to be continuous, but the bonding jumpers only have to comply with 250.64(A)(B) and (E), per 250.53(C).

Edit to add:
If it is a 200A service, be aware that 250.64(F) would require that the conductor going to the ground rod, and the conductor going to the water pipe, be sized according to the water pipe's requirement. So a #4 would be brought to the ground rod, and the bonding jumper would also be a #4. If a second ground rod is driven for 250.56, then the bonding jumper connecting that rod to the first rod could be a #6.
Click to expand...

Thank you george, I really feel that the method you describe is a safe ge system. I may have become confused after reading NEC 250.50 All grounding electrodes described in 250.52(A)(1) through (A) (6) (that are PRESENT) must be bonded together to form the grounding electrode system. I thought that because the waterpipe was present and none of the others described were not, that the waterpipe was required to be the main electrode. After giving it more thought I realise that the ground rod (rods) become present after they are driven.

Well no one can call me a know it all or this is how we do it in my town inspector. Thanks for the help also John.

I will require the electrician to bond the 2 ground rods together with a gec and terminate it at the neutral of the main disconnect and it will be a done deal.
 
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