Grd. rod question

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Buck Parrish

Buck Parrish

Senior Member
Location
NC & IN
I don't have my code book with me today. The inspector is saying my ground rods are to small.
We used the same ones we've ever used, 8' long.
Can some one help me out with a reference quote from the 08 book. I'm in NC today.

He's picky, he says there only 5' 10" apart :)
 
Buck Parrish said:
I don't have my code book with me today. The inspector is saying my ground rods are to small.
We used the same ones we've ever used, 8' long.
Can some one help me out with a reference quote from the 08 book. I'm in NC today.

He's picky, he says there only 5' 10" apart :)
Click to expand...

250.52(A)(5) Rod and Pipe Electrodes. Rod and pipe electrodes
shall not be less than 2.44 m (8 ft) in length and shall
consist of the following materials.

250.53(B) Electrode Spacing. Where more than one of the electrodes
of the type specified in 250.52(A)(5) or (A)(7) are
used, each electrode of one grounding system (including
that used for air terminals) shall not be less than 1.83 m
(6 ft) from any other electrode of another grounding system.
Two or more grounding electrodes that are bonded
together shall be considered a single grounding electrode
system.
 
Thanks Derek,
So it does not mention any thing about thickness?
We used the same 8 ft ones we've always used.
I guess thier 7/8 " x 8'
Thanks
 
Buck Parrish said:
Thanks Derek,
So it does not mention any thing about thickness?
We used the same 8 ft ones we've always used.
I guess thier 7/8 " x 8'
Thanks
Click to expand...

(5) Rod and Pipe Electrodes. Rod and pipe electrodes
shall not be less than 2.44 m (8 ft) in length and shall
consist of the following materials.

(b) Grounding electrodes of stainless steel and copper
or zinc coated steel shall be at least 15.87 mm (5⁄8 in.) in
diameter, unless listed and not less than 12.70 mm (1⁄2 in.)
in diameter.
 
We have a ground rod discussion going on in another forum but I'm accustomed to an 8' long ground rod that is 5/8" dia cu clad.
I really don't know if the 5/8" is critical electrically but it sure is darned important when they have to be beefy enough for you to drive them in.
There is no reason to skimp of the 6' min. apart though. Going more than 6' prevents a challenge.
 
Buck Parrish said:
I don't have my code book with me today. The inspector is saying my ground rods are to small.
We used the same ones we've ever used, 8' long.
Can some one help me out with a reference quote from the 08 book. I'm in NC today.

He's picky, he says there only 5' 10" apart :)
Click to expand...

Is this a situation where you are leaving the top/clamp above grade? If so, an 8' rod would be to short. On the diamater I would agree with infinity. As for the 5'10" part, well, thats pretty picky-you could probably push it apart for the needed 2" if it is just in soil.
 
250.53(B) Electrode Spacing. Where more than one of the electrodes
of the type specified in 250.52(A)(5) or (A)(7) are
used, each electrode of one grounding system (including
that used for air terminals) shall not be less than 1.83 m
(6 ft) from any other electrode of another grounding system.
Two or more grounding electrodes that are bonded
together shall be considered a single grounding electrode
system.
Click to expand...
If each ground rod is bonded together that makes them a grounding electrode
They cant be more than 6 feet from another grounding system.

I read this as "can't be closer to ufer ground, water ground, rebar ground, OR does it mean can't be within 6 feet of another ground rod which is connected to the other ground rod which is called "a single grounding electrode system."

My inspectors have made me move my ground rod 3 inches before too. Like 98 ohms vs 98 ohms makes a difference.

I like to sink 10 foot long 3/4 inch ground rods on commercial jobs, does this put me in violation?
And no it doesnt get below 25 ohms, ever.
 
GUNNING said:
If each ground rod is bonded together that makes them a grounding electrode
They cant be more than 6 feet from another grounding system.

I read this as "can't be closer to ufer ground, water ground, rebar ground, OR does it mean can't be within 6 feet of another ground rod which is connected to the other ground rod which is called "a single grounding electrode system."

My inspectors have made me move my ground rod 3 inches before too. Like 98 ohms vs 98 ohms makes a difference.

I like to sink 10 foot long 3/4 inch ground rods on commercial jobs, does this put me in violation?
And no it doesnt get below 25 ohms, ever.
Click to expand...

Where are you getting the no more than 6' from? Also if they're part of the same system two different types of electrodes can be less than 6' apart.
 
texie said:
As for the 5'10" part, well, thats pretty picky-you could probably push it apart for the needed 2" if it is just in soil.
Click to expand...

But why put them that close that you get into that situation. I usually drive one and use the other 8' rod as a measure. Minimum 6' but nothing stops you from going 8' or more. In fact the further apart the better is what I understand.
 
Dennis Alwon said:
But why put them that close that you get into that situation. I usually drive one and use the other 8' rod as a measure. Minimum 6' but nothing stops you from going 8' or more. In fact the further apart the better is what I understand.
Click to expand...

In the city of Seattle, the ground rods are required to be at least 8' apart.
 
Dennis Alwon said:
But why put them that close that you get into that situation. I usually drive one and use the other 8' rod as a measure. Minimum 6' but nothing stops you from going 8' or more. In fact the further apart the better is what I understand.
Click to expand...
HTML:

My helper said he was useing up the little pieces of #6 on the truck. Thier was enough in the extra bent over to go 6'1". So that's what we ended up doing.
Still don't know where the inspector got the ideal it was the wrong rod. His quote " Use the correct type of rods"
 
Buck Parrish said:
My helper said he was useing up the little pieces of #6 on the truck. Thier was enough in the extra bent over to go 6'1". So that's what we ended up doing.
Still don't know where the inspector got the ideal it was the wrong rod. His quote " Use the correct type of rods"
Click to expand...

Are you in NC or Ind doing this work. Where if NC
 
I'm in NC - Most of the areas I work at in INDY are very rual and do not have an inspections office, You can build an entire house with out a permit, except a septic system permit.


On a side note' The handy men only carry plumbing pipe. It works with electrical and water. Where as electrical conduit leaks. hahaha:happyno:
 
special expensive gray water pipe ground.

special expensive gray water pipe ground.

So they use 3/4 gray rigid PVC as a ground pipe? How do they drive it into all that rock? :dunce:
 
I think the inspector problem is not the 8' ground rods, but rather the distance.
They're supposed to be 10' apart.

Buck Parrish said:
I don't have my code book with me today. The inspector is saying my ground rods are to small.
We used the same ones we've ever used, 8' long.
Can some one help me out with a reference quote from the 08 book. I'm in NC today.

He's picky, he says there only 5' 10" apart :)
Click to expand...
 
as it was shown in an earlier post the rods need to be atleast 6 foot apart. one of my good friends who is an electrical engineer told me that IEEE recomends that the rods be appart atleast as far as they are long. so if you use 8 foot rods you should be 8 foot appart. he also told me that they would recomend that you double that distance for them to be more effective.
 
as it was shown in an earlier post the rods need to be atleast 6 foot apart.  one of my good friends who is an electrical engineer told me that IEEE recomends that the rods be appart atleast as far as they are long.  so if you use 8 foot rods you should be 8 foot appart.  he also told me that they would recomend that you double that distance for them to be more effective.
 
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