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Ground rod distance from foundation?

Our co-op requires two ground rods 10 feet apart.
legal authority? I do not know. I do know they will not install a meter without two ground rods installed.
 
Francis Vineyard said:
The bold type in ICE post is from 250.64 for protection where exposed; and would not need to comply with the burial depth of 300.5.

(B) Securing and Protection Against Physical Damage.
Where exposed, a grounding electrode conductor or its enclosure
shall be securely fastened to the surface on which it is
carried. Grounding electrode conductors shall be permitted to
be installed on or through framing members. A 4 AWG or
larger copper or aluminum grounding electrode conductor
shall be protected if exposed to physical damage. A 6 AWG
grounding electrode conductor that is free from exposure to
physical damage shall be permitted to be run along the smi'ace
of the building construction without metal covering or protection
if it is securely fastened to the construction; otherwise, it
shall be protected in rigid metal conduit RMC, intermediate
metal conduit (TMC), rigid polyvinyl chloride conduit (PVC),
reinforced thermosetting resin conduit (RTRC), electrical metallic
tubing EMT, or cable armor. Grounding electrode conductors
smaller than 6 A WG shall be protected in (RMC),
TMC, PVC, RTRC, (EMT) , or cable armor. Grounding electrode
conductors and grounding electrode bonding jumpers
shall not be required to comply with 300.5.
Click to expand...
Actually Francis, the bold is found at 300.5(B)
 
ICE, enlighten us.

300.5 Underground Installations.

(A) Minimum Cover Requirements. Direct-buried cable
or conduit or other raceways shall be installed to meet the
minimum cover requirements of Table 300.5.

(B) Wet Locations. The interior of enclosures or raceways
installed underground shall be considered to be a wet location.
Insulated conductors and cables installed in these enclosures
or raceways in underground installations shall comply
with 310.10(C). Any connections or splices in an underground
installation shall be approved for wet locations.

(C) Underground Cables and Conductors Under Buildings.
Underground cable and conductors installed under a
building shall be in a raceway.
 
mtlogcabin said:
Our co-op requires two ground rods 10 feet apart.
legal authority? I do not know. I do know they will not install a meter without two ground rods installed.
Click to expand...
That's what I keep tryhing to tell you guys, it's a utility requirement not a code requirement, do you guys even have the maps showing soils conditions to even determine the number of ground rods necessary? Do you know how to determine the number of ground rods if you were given the soils conditions?
 
Do these maps show when you only need one rod? What if they are using a medal pipe of a water line or a ground ring etc.?
Hardly ever see rods for new houses anymore. They mostly use the footing rebar now.

Do you make them do a ohm test if only one rod is OK according to the maps as required by code?
 
Rick18071 said:
Do these maps show when you only need one rod? What if they are using a medal pipe of a water line or a ground ring etc.?
Hardly ever see rods for new houses anymore. They mostly use the footing rebar now.

Do you make them do a ohm test if only one rod is OK according to the maps as required by code?
Click to expand...
We use all three, U-fer, steel gas pipe, and copper water pipe I don't know what they do for these homes with plastic pipe. As I recall the map showed two areas, one for one rod and the other for two rods, then where were all kinds of specifications and diagrams.
 
"Grounding electrode conductors and grounding electrode bonding jumpers shall not be required to comply with 300.5."

I located this in the 2014 NEC, Section 250.64 (B). Thanks ! Very helpful, we have not adopted this version yet. This confuses me somewhat. I could make the argument of burial depth being used as physical protection for the GEC in pre-2014 NEC. This change takes away the protection that it had previously received from 300.5 and validates the original concern of installing a grounding electrode 7' from the foundation. How is the GEC protected at this point? Somewhere else in the code? Obviously protection from physical damage is important, as 250.64 (B) indicates. Is the following, quoted part of that section implying that the GEC installed underground is to be installed in a protective covering that doesn't have to comply with burial depths?

"otherwise, it shall be protected in rigid metal conduit RMC, intermediate metal conduit (IMC), rigid polyvinyl chloride conduit (PVC), reinforced thermosetting resin conduit (RTRC), electrical metallic tubing EMT, or cable armor. Grounding electrode conductors smaller than 6 AWG shall be protected in (RMC),
IMC, PVC, RTRC, (EMT), or cable armor."

Any idea where we find reason statements for code changes to the NEC?
 
ICE said:
Uh Oh Francis I'm sorry....I am full of it.
Click to expand...
Aren't we all from time to time! Wasn't sure but at least you started us down the path to make the job easier. Thanks

2017 NEC
250.64(B)(4) In contact with the Earth. Grounding electrode conductors and grounding electrode bonding jumpers in contact with the earth shall not be required to comply with 300.5, but shall be buried or otherwise protected if subject to physical damage.
 
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rgrace said:
"Grounding electrode conductors and grounding electrode bonding jumpers shall not be required to comply with 300.5."

I located this in the 2014 NEC, Section 250.64 (B). Thanks ! Very helpful, we have not adopted this version yet. This confuses me somewhat. I could make the argument of burial depth being used as physical protection for the GEC in pre-2014 NEC. This change takes away the protection that it had previously received from 300.5 and validates the original concern of installing a grounding electrode 7' from the foundation. How is the GEC protected at this point? Somewhere else in the code? Obviously protection from physical damage is important, as 250.64 (B) indicates. Is the following, quoted part of that section implying that the GEC installed underground is to be installed in a protective covering that doesn't have to comply with burial depths?

"otherwise, it shall be protected in rigid metal conduit RMC, intermediate metal conduit (IMC), rigid polyvinyl chloride conduit (PVC), reinforced thermosetting resin conduit (RTRC), electrical metallic tubing EMT, or cable armor. Grounding electrode conductors smaller than 6 AWG shall be protected in (RMC),
IMC, PVC, RTRC, (EMT), or cable armor."

Any idea where we find reason statements for code changes to the NEC?
Click to expand...
Will this answer will be satisfactory;

"I will be honest with you; I really pushed for subsection (4) In Contact with Earth. One of my pet peeves when I do an electrical service inspection is to find a grounding electrode conductor running along the surface of the ground without any protection … just lying there. The 2014 language left the reader with the impression that a grounding electrode conductor lying on the earth didn’t need protection – ever. That was never the intent. It needs protection if it is subject to physical damage. The new language states that a grounding electrode, if in contact with the earth, shall not be required to comply with 300.5, but shall “be buried or otherwise protected if subject to physical damage.” So if you are an electrical inspector and feel that the grounding electrode conductor is subject to people walking on it, kicking it, tripping on it, or whatever do me a big favor and have the contractor bury it a little bit. I really have to thank my code panel (CMP-5) for adding this new language. It makes enforcement so much easier for the inspector!"

Source: Nick’s Picks: Top 10 Electrical Code Changes NEC 2017
 
Conarb, Bonding and grounding are different, under the NEC, you can use rods, or if you use the water pipe you have to supplement with rods, but technically you only need one grounding electrode (with the GEC running to it), and the others, (where present), get bonded....you can't bond plastic water pipe (I know Cali is weird with that though)
 
steveray said:
Conarb, Bonding and grounding are different, under the NEC, you can use rods, or if you use the water pipe you have to supplement with rods, but technically you only need one grounding electrode (with the GEC running to it), and the others, (where present), get bonded....you can't bond plastic water pipe (I know Cali is weird with that though)
Click to expand...
All I know is we do what the utility requires to give us service, and that includes getting the inspector to call them clearing it along with their requirements.
 
conarb said:
Not around here you don't, our utility requires 4 bonds, Ufer, gas, water, and driven rods.
Click to expand...
Gas pipe should never be used as an electrode. It should always be bonded. That can be accomplished by the equipment ground for a gas appliance such as a furnace or a jumper to a water pipe at the water heater. The gas pipe in the ground must be separated from the bond by a dialectic union......a twist on that is the introduction of CSST which requires a solid #6 bonding jumper between the gas hard pipe and the grounding electrode system.
 
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Mark K said:
Is it possible that the inspector is imposing his preferences as opposed to what the code says?.
Click to expand...

Francis Vineyard said:
Will this answer will be satisfactory;
” So if you are an electrical inspector and feel that the grounding electrode conductor is subject to people walking on it, kicking it, tripping on it, or whatever do me a big favor and have the contractor bury it a little bit.
Click to expand...

What a quandary, One forum member imply's I may be imposing my preference and the other, like me want's it safe.

I blame this on new plastic water lines being used for water service, we've lost our water pipe ground source. When an existing home upgrades the electrical service we have altered the code by allowing an option of TWO rods, that have to be a minimum of 6-ft apart. Distance from a foundation may be difficult to achieve in some situations. In this case the contractor hit rock so he decided to go further out from the home with the ground wire less than 6-inches below grade. I suggested that the rod be installed at 45° per code, with contractor resistance. Claimed he would not be able to remove the driven rod and it would be an additional expense. The end result is the grounding wire and grounding rod is below grade.

Conarb has mentioned additional rod requirements on some of his projects and some of us may not be aware of our soil types, that is not the case here, I have the County Soil Type Survey. There are some areas I have heard that have had problems with the rock hard caliche, the Las Vegas area I believe.

Conarb, my avatar is a photo of the AT6 we owned when I was in HS, that paint job was the results of a whole summer of sanding after our plane partner hit a top of a telephone pole on a night landing:eek:. He walked away from the crash and said "the planes all yours!" After that we found repair parts out in CA near SF to put it back together.
 
conarb said:
How do you know the difference btween bonding and grounding? It all looks the same to a dumb builder like me.
Click to expand...

This is a pretty good book to have in your library: Soares book on grounding and bonding.
 
We say one rod with 25 ohms or 2 max regardless of resisitance, no resistance test...."subject to damage" is the purview of the inspector, not rod placement....
 
NEC only requires that the GEC must be continuous from the electrode to the panel GEC connection, not rod to rod. You could use a grounding clamp on the first rod, then a grounding clamp to the next rod and use another clamp there. They can even be spliced if it is an irreversible splice and is rated for use as such.
 
There is no "max" for number of ground rods. You could put in a dozen if you wanted to....There is a "supplementary grounding electrode" requirement if ground resistance is greater than 25 ohms....but, really, how many have a ground resistance tester and know how to use it? Most just use 2 8' min. rods at least 6 ft apart and call it good. As far as utility jurisdiction, as a utility metering tech, I never got involved in grounding and bonding unless it was obvious that there was a safety hazard, such as a missing MBJ or improperly terminated GEC (such as the GEC terminating on the ground bus but not having a bus bar or jumper to the neutral bar). NEC 250.24.A.4
 
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