Ground Rod Placement Suggestions

jamiedolan · 10-03-2008, 01:07 AM

I bought 2 ground rods I am planning on installing maybe tomorrow. Can someone please tell me the current regs for NEC 2008 on where I can place them? i.e. distance from the house, and distance from each other. Is 6gage wire still correct? Do I bond them together, then run one cable to the panel?
They are the rods that look like copper they call them 5/8 inch, however one of the is just a smidgen thinner (1/8 to 1/16 slimmer).

Is there a limit to how far I can run the ground cable? The part of the yard I want to put them in would cause me to have about a 40 foot run for the ground cable.

Thanks
Jamie

InPhase277 · 10-03-2008, 11:12 AM

Quote:

Originally Posted by jamiedolan

I bought 2 ground rods I am planning on installing maybe tomorrow. Can someone please tell me the current regs for NEC 2008 on where I can place them? i.e. distance from the house, and distance from each other. Is 6gage wire still correct? Do I bond them together, then run one cable to the panel?
They are the rods that look like copper they call them 5/8 inch, however one of the is just a smidgen thinner (1/8 to 1/16 slimmer).

Is there a limit to how far I can run the ground cable? The part of the yard I want to put them in would cause me to have about a 40 foot run for the ground cable.

Thanks
Jamie

I am not aware of any code right off hand that says you can't place the rods 40' from the house, and I don't have a code book handy. But as a general rule, you want to keep the grounding electrodes as close to the service as possible. #6 is as large as the NEC requires the conductor be, but I have worked in some jurisdictions where #4 was required. And the distance between the two rods is a minimum of 6 ft, the larger the better. We usually just loop the wire from rod to rod then to the service (clamping of course).

jamiedolan · 10-03-2008, 12:17 PM

Quote:

Originally Posted by InPhase277

I am not aware of any code right off hand that says you can't place the rods 40' from the house, and I don't have a code book handy. But as a general rule, you want to keep the grounding electrodes as close to the service as possible. #6 is as large as the NEC requires the conductor be, but I have worked in some jurisdictions where #4 was required. And the distance between the two rods is a minimum of 6 ft, the larger the better. We usually just loop the wire from rod to rod then to the service (clamping of course).

It would actually still be close to the house. My idea is that I would eventually move the service entrance to the far end of the house where it would be more out of the way (about allow expansion to the back of the house).

So the cable run would end up being about 40' but, would be within 10 feet or so of the house. Actually, I am not sure how far away from the house I should place the rods.

Jamie

johnjf0622 · 10-03-2008, 04:33 PM

You can also contact your town electrical inspectors office. Just ask for guidelines regs for the task you want to do. I have always put the ground rods closed to the house no more then 1 foot off the foundation. never hit the footing to the foundation that way. You also don't want to cause a tripping hazard or find it with you lawn mower. As far as putting 2 in (does what you are doing call for 2) like I said it depends on what your task calls for. I work for the railroad and when we put in the signal bungalows it calls for a ground grid. But putting a ground grid for a house would be a new one for me unless you have lighting rods I would think. I never put one for a house. Hope this helps.

John

jamiedolan · 10-03-2008, 04:52 PM

Quote:

Originally Posted by johnjf0622

You can also contact your town electrical inspectors office. Just ask for guidelines regs for the task you want to do. I have always put the ground rods closed to the house no more then 1 foot off the foundation. never hit the footing to the foundation that way. You also don't want to cause a tripping hazard or find it with you lawn mower. As far as putting 2 in (does what you are doing call for 2) like I said it depends on what your task calls for. I work for the railroad and when we put in the signal bungalows it calls for a ground grid. But putting a ground grid for a house would be a new one for me unless you have lighting rods I would think. I never put one for a house. Hope this helps.

John

Hello;

The reason I am putting them in is that I plan to upgrade my service to 200A, which will very likely happen during the winter months, here in Wisconsin, the ground get frozen pretty solid, and I can only imagine how hard it would be to get a rod installed in the winter months here.

It is my understanding that it is now code to have 2 grounding rods installed for your electrical service, so my understanding is that they will either want to install 2 new rods when the service is upgraded or they will want to be able to verify that they have been properly installed.

I just want to get the rods properly installed prior to winter so they are there and ready to go, and we don't have to mess with this in the dead of winter when we change the panel / upgrade the service.

So does anyone know if 2 grounding rods (8' copper color rods 5/8 inch thick) is what is required in general for electrical upgrades?

I may give the city a call on this and see if they can give me a quick answer to it without asking lots of questions. Since they won't even be used until later when I do the full upgrade - that will of course require a permit. But I don't really want to have to get a permit to just pound in a couple rods now that are not even going to be hooked up till later.

Thanks

Jamie

InPhase277 · 10-03-2008, 04:53 PM

Quote:

Originally Posted by johnjf0622

As far as putting 2 in (does what you are doing call for 2) like I said it depends on what your task calls for. I work for the railroad and when we put in the signal bungalows it calls for a ground grid. But putting a ground grid for a house would be a new one for me unless you have lighting rods I would think. I never put one for a house. Hope this helps.

John

The code is such that a single ground rod must have a resistance of 25 ohms or less to earth. And that number must be verified. But, if you add a second rod, there is no requirement for verification. It's just easier to do 2 rods.

jamiedolan · 10-03-2008, 05:56 PM

Quote:

Originally Posted by InPhase277

The code is such that a single ground rod must have a resistance of 25 ohms or less to earth. And that number must be verified. But, if you add a second rod, there is no requirement for verification. It's just easier to do 2 rods.

Per NEC -A minimum of 6 feet apart, correct?
Jamie

Jim Port · 10-03-2008, 06:16 PM

Yes, 6' minimum between rods.

johnjf0622 · 10-03-2008, 09:35 PM

All righty then goes to prove you learn something new everyday. LOL.
john

Marvin Gardens · 10-04-2008, 09:00 AM

Grounding rods vary from location to location. It depends on the soil and who wrote the local code.

At my main home we only have to go down 6 feet since the soil is moist year round. At my vacation home we have to have 2 rods a foot apart and go down 12 feet because it is very dry. Even at that depth it is hard to get consistent grounding in some systems. One rancher had to go down 20 feet with 4 rods to get consistent grounding. He initially followed code but still had that "buzz" when touching metal appliances so he had more grounds put in and that worked.

He was telling me that he would get good ground on rainy days and for a week or so after that but it would always get real bad in the late summer.

jamiedolan · 10-04-2008, 11:46 AM

Quote:

Originally Posted by Marvin Gardens

Grounding rods vary from location to location. It depends on the soil and who wrote the local code.

At my main home we only have to go down 6 feet

I thought the NEC set the minimum standards, and that the state or local level could make it more restrictive if they choose, not less.

I didn't think that anyone could set standards that were less than the NEC code. i.e. I thought a 6 foot rod was always illegal, am I wrong?

Jamie

InPhase277 · 10-04-2008, 12:28 PM

Quote:

Originally Posted by jamiedolan

I thought the NEC set the minimum standards, and that the state or local level could make it more restrictive if they choose, not less.

I didn't think that anyone could set standards that were less than the NEC code. i.e. I thought a 6 foot rod was always illegal, am I wrong?

Jamie

If the NEC has been adopted as law in the jurisdiction, then it is the minimum standard. But there is no Federal law that requires it to be adopted everywhere. Individual jurisdictions are free to make there own codes, or adopt other codes and amend them as they see fit. Yet other areas have no adopted code at all or an inspection department to enforce standards.

InPhase277 · 10-04-2008, 12:32 PM

Quote:

Originally Posted by Marvin Gardens

Grounding rods vary from location to location. It depends on the soil and who wrote the local code.

At my main home we only have to go down 6 feet since the soil is moist year round. At my vacation home we have to have 2 rods a foot apart and go down 12 feet because it is very dry. Even at that depth it is hard to get consistent grounding in some systems. One rancher had to go down 20 feet with 4 rods to get consistent grounding. He initially followed code but still had that "buzz" when touching metal appliances so he had more grounds put in and that worked.

He was telling me that he would get good ground on rainy days and for a week or so after that but it would always get real bad in the late summer.

Strange situation. For one, ground rods spaced further apart are better than ground rods placed next to each other, such as your two placed a foot apart. And if your rancher friend is getting zapped when touching metal objects, then his problem isn't an earth ground, but is a bonding problem somewhere in his system. More rods may have alleviated the problem, but they surely aren't the fix.

It's been said many times here, but one more won't hurt. Ground rods and other grounding electrodes serve no purpose for the normal function of the electrical system, including short circuits. If you had no earth grounding means at all, your wiring would still work properly. We only use earth grounds to limit the voltage on the system imposed by lightning and other high voltage events *outside* of our system.

Marvin Gardens · 10-04-2008, 12:36 PM

Quote:

Originally Posted by jamiedolan

I thought the NEC set the minimum standards, and that the state or local level could make it more restrictive if they choose, not less.

I didn't think that anyone could set standards that were less than the NEC code. i.e. I thought a 6 foot rod was always illegal, am I wrong?

Jamie

That would be news to be. I just put in some ground and the inspector told me 6 feet in the ground and 12 in separation. I still have my water pipe ground so maybe that has something to do with it.

Marvin Gardens · 10-04-2008, 12:41 PM

Quote:

Originally Posted by InPhase277

Strange situation. For one, ground rods spaced further apart are better than ground rods placed next to each other, such as your two placed a foot apart. And if your rancher friend is getting zapped when touching metal objects, then his problem isn't an earth ground, but is a bonding problem somewhere in his system. More rods may have alleviated the problem, but they surely aren't the fix.

It's been said many times here, but one more won't hurt. Ground rods and other grounding electrodes serve no purpose for the normal function of the electrical system, including short circuits. If you had no earth grounding means at all, your wiring would still work properly. We only use earth grounds to limit the voltage on the system imposed by lightning and other high voltage events *outside* of our system.

It could be coincidence. He said the problem went away once he put in the other two rods. He put in another wire and went to the other side of the house for those.

I know that he also had the panel replaced a few months after that. He has a small fire in his wood furnace and destroyed some of his wiring.