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kherr
Premium
join:2000-09-04
Collinsville, IL
Reviews:
·Charter

Bare ground need conduit ??

Does a bare ground going to a ground rod need conduit?? I'm planning to run from a 100A sub panel to a rod in addition to the ground wire that goes back to the service ground. It's a ways back to the service panel (100' as the ridge runs) and feel a little better doing so. Does this require conduit?? I happened to come into a spool of #6 bare years ago when it fell off an Illinois Power truck that was in front of me, so cost is not a consideration. And YES it did fall off. I'll be running it as if it was romex, so it won't for example be run exposed underneath floor joists. If it does I'll probably use smurf tube since I have a lot of it hanging around.

Or is this not a good idea??



LazMan
Premium
join:2003-03-26
canada

I'm not familar with IL codes, other then to know they've got some 'unique' requirements...

Up here, it's perfectly accepetable to run the grounding conductor free, as long as it's protected from mechanical damage... It actually violates code to run it through a metalic conduit unless you're using a bonding-bushing at one end.



alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1
reply to kherr

It's fine, as said, make sure it's protected from mechanical damages (like romex).

I hope you aren't doing this to avoid running a grounding conductor between the subpanel and the main panel. (I guess you aren't since you said you have a spool of #6 to waste).

Just a heads up: Make sure your subpanel doesn't bond the neutral and ground. That's your main panel's job.



davidg
Good Bye My Friend
Premium,MVM
join:2002-06-15
none
reply to kherr

ask your AHJ, they can say if it is acceptable or not.

we had one that made us install a new ground rod after a meter base replacement because the original grounds go into the wall and emerge at a now buried rod that was covered in a concrete slab. since he could not "see" it he held it in violation even though it was apparent by the number of grounds heading to the same point from various outbuildings and a tower.
--
Lack of Preparation on YOUR Part does NOT Constitute an Emergency on Mine!



nunya
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12
Reviews:
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·voip.ms
·surpasshosting
reply to kherr

I'm not sure I follow what you are doing here, but - Yes and No. Collinsville follows the NEC.
Anywhere the ground wire is subject to damage, it must be protected. Typically, this is a "no" for an indoor run.
On the outside of the house, C-Ville does require the ground wire to be in conduit (not ENT!) running down to the rod.
If you have any questions, call Bob the city inspector.
--
If someone refers to herself / himself as a "guru", they probably aren't.



ArgMeMatey

join:2001-08-09
Milwaukee, WI
kudos:2
Reviews:
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said by nunya:

On the outside of the house, C-Ville does require the ground wire to be in conduit (not ENT!) running down to the rod.

Just curious: Would Sch 40 PVC be acceptable, or would metal be required?


nunya
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12

Rigid PVC is OK by code.


laserfan

join:2005-01-14
Texas
reply to kherr

said by kherr:

I'm planning to run from a 100A sub panel to a rod in addition to the ground wire that goes back to the service ground. It's a ways back to the service panel (100' as the ridge runs) and feel a little better doing so.

I thought it was a no-no to have a ground rod that was "remote" from the main service panel--that there was supposed to be just one ground point in a system.

Who can clarify this--or is there more than one way to skin the cat? I might've thought additional ground rods at a remote building would be A Good Thing...

robbin
Premium,MVM
join:2000-09-21
Leander, TX
kudos:1

Additional rods have to be bonded to the main ground with at least a 6 gauge wire.



whizkid3
Premium,MVM
join:2002-02-21
Queens, NY
kudos:9

1 edit
reply to kherr

said by kherr:

I'm planning to run from a 100A sub panel to a rod in addition to the ground wire that goes back to the service ground. It's a ways back to the service panel (100' as the ridge runs) and feel a little better doing so.
Or is this not a good idea??

If the sub-panel is in the same building, then I have to question why you are doing this; and how you are possibly going to make it even legal. It will also be a waste of wire & materials. To begin with; any 'sub-panel' already must have a ground wire running back to the equipment grounding point in the next panel upstream. It must run with the power conductors and neutral. What is your second wire going to do that the first one can not?

If you really wanted to improve your grounding electrode system, you would not have to tie it into your sub-panel at all; primarily because any ground fault must travel first to the neutral-ground bond at your service entrance, before it can work to trip the breaker. Putting a ground rod nearby; with a wire back to the main grounding electrode system will accomplish the same thing, with less work and materials. Its not likely needed, anyway.

If you really want to know how to protect it, here is a good synopsis I wrote some time ago which has some additional helpful information:
»Re: Installing a ground rod

Don't take it the wrong way, but personally, I recommend selling the wire and using the money to hire a licensed contractor to install the sub-panel properly. Maybe you can work out a barter arrangement. Seriously.

said by laserfan:

I thought it was a no-no to have a ground rod that was "remote" from the main service panel--that there was supposed to be just one ground point in a system.

Not correct. Having auxillary ground rods is done all the time. A water pipe and ground rod represent two points and is done all the time. Buildings with structural steel use the steel columns as electrodes (or have ground rods at each column). Many buildings have buried grids or complete ground rings around the building. Some facilites have a ground-plane providing 'infinite' grounding points.

The concern is how its done; most if not all homeowners, should not be monkeying around with their grounding electrode system. They don't know what it does; they don't know the theory and they don't know the code requirements. Anything beyond a single ground rod or water pipe gets a lot more complicated in regards to code requirements and is not normally needed, anyway.

laserfan

join:2005-01-14
Texas

said by whizkid3:

Anything beyond a single ground rod or water pipe gets a lot more complicated in regards to code requirements and is not normally needed, anyway.

Hmmm robbin said addt'l rods need a 6ga tie to the original, and you say it's "a lot more complicated" than that.

I wonder which is true?

I did mis-read the OP's question; I thought he was talking a bldg 100' away, but it seems it might be one building. In any case, my ? was e.g. for a service panel (with rod) to a house (no rod) to a separate garage (no rod). If a ground wire exists back to the main service panel, can add'tl rods be installed at the remote buildings.


whizkid3
Premium,MVM
join:2002-02-21
Queens, NY
kudos:9

said by laserfan:

I wonder which is true?

Robbin said a minimum of 6 AWG. THey are both true. I said nothing to the effect that its more complicated than ...robbins post.. as you are trying to make it sound by comparing the two in the same sentance.

said by laserfan:

In any case, my ? was e.g. for a service panel (with rod) to a house (no rod) to a separate garage (no rod).

This wasn't your question and is not what I responded to. Maybe it is what you wanted to ask.

said by laserfan:

If a ground wire exists back to the main service panel, can add'tl rods be installed at the remote buildings.

For separate buildings, where allowed, there must be a ground wire back to the next upstream panel. Yes, you can have a separate ground rod at the separate building, and in most cases its a code requirement.


cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7

1 recommendation

reply to laserfan

said by laserfan:

Hmmm robbin said addt'l rods need a 6ga tie to the original, and you say it's "a lot more complicated" than that.

I wonder which is true?

They aren't mutually exclusive of each other. Robbin's comment is but one of many requirements in section 250 of the NEC.

Generally speaking, with regard to electrical matters, anything that Whizkid and Nunya comment on like this is more or less NEC gospel as the resident sparkys. Robbin is also a very trusted resource here, and I've never known him to give wrong advice. Unless it's in direct contradiction to something Whizkid or Nunya say, what he says can be relied on as well. If it is in contradiction, then it's likely that there was a misunderstanding somewhere and that what ever was said may not be specifically applicable.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

said by cdru:

quote:
Generally speaking, with regard to electrical matters, anything that Whizkid and Nunya comment on like this is more or less NEC gospel as the resident sparkys.
+1 These two are the resident electrical experts. You can't go wrong using their advice.


cableties
Premium
join:2005-01-27

said by Jack_in_VA:

said by cdru:

quote:
Generally speaking, with regard to electrical matters, anything that Whizkid and Nunya comment on like this is more or less NEC gospel as the resident sparkys.
+1 These two are the resident electrical experts. You can't go wrong using their advice.

+2
But remember to always check with local codes if unsure.
(I did isolated grounds once. Two rod driven x-feet apart. Cable buried. ...damn if some landscaper dug one rod up, cut cable...)
--
Splat

laserfan

join:2005-01-14
Texas
reply to kherr

Attempting to summarize then, additional ground rods at separate buildings are acceptable if tied-together back to the main service panel ground rod with 6AWG wire.

Local codes rule (though in my case there are no local codes, only the NEC, and no inspectors I could consult with).

I apologize to the OP if I've taken this thread off-topic. When I read "100ft ridge" I was not think of a roof peak, but rather a ridge of land.



cdru
Go Colts
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join:2003-05-14
Fort Wayne, IN
kudos:7

1 recommendation

said by laserfan:

Attempting to summarize then, additional ground rods at separate buildings are acceptable if tied-together back to the main service panel ground rod with 6AWG wire.

250.32 requires that buildings and structures supplied by a feeder or branch circuit have it's own ground rod unless it's only a single branch circuit (including a MWBC). If it is a feeder or multiple branch circuits, the required ground rod must be installed and bonded back to the primary rod with 6AWG.


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:6

said by cdru:

If it is a feeder or multiple branch circuits, the required ground rod must be installed and bonded back to the primary rod with 6AWG.

This is incorrect.

I'll leave it to the duly anointed to explain it to you.


LazMan
Premium
join:2003-03-26
canada

said by John Galt:

said by cdru:

If it is a feeder or multiple branch circuits, the required ground rod must be installed and bonded back to the primary rod with 6AWG.

This is incorrect.

I'll leave it to the duly anointed to explain it to you.

Oh no - not ANOTHER bonding vs. bonded vs. grounding vs. grounded thread?


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:6

said by LazMan:

Oh no - not ANOTHER bonding vs. bonded vs. grounding vs. grounded thread?

Actually, it's none of those...


LazMan
Premium
join:2003-03-26
canada
reply to kherr

Then I too, shall wait for those in the know to englighten us...



Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to cdru

said by cdru:

said by laserfan:

Attempting to summarize then, additional ground rods at separate buildings are acceptable if tied-together back to the main service panel ground rod with 6AWG wire.

250.32 requires that buildings and structures supplied by a feeder or branch circuit have it's own ground rod unless it's only a single branch circuit (including a MWBC). If it is a feeder or multiple branch circuits, the required ground rod must be installed and bonded back to the primary rod with 6AWG.

This is incorrect and my AHJ "explained" it to my electrician who had to remove the wire to the new ground rod he drove in at my detached garage and run a separate #6 from the panel to the existing ground rod for the home service.


nunya
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join:2000-12-23
O Fallon, MO
kudos:12
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1 recommendation

Your inspector was wrong and the electrician was right. At an outbuilding with a feeder other than a branch circuit (E.G. sub-panel) then a grounding electrode is required (doesn't have to be a ground rod, but that's typically the defacto choice). The 4-wire circuit is required too. Technically, the feeder EGC does not need to be a #6 and is sized by 250.122.
If you drill down through the code far enough 250.32 (and this one is a tough one), you'll wind up at section III and 250.66.
There GEC at that location (the outbuilding) is sized by 250.66, where the minimum size GEC is #8 copper.
If you look at 250.66 it answers all the questions. No GEC going to a ground rod shall be required to be larger than #6 copper regardless of table 250.66.
If you go back to 250.53, they say that can't just use a single ground rod unless the resistance can be proved to 25 ohms. Most inspectors aren't going to call anybody out on this.
Any additional ground rads at the location (outbuilding) must be bonded together by, you guessed it, #6. Even if the GEC is a #8, and the EGC is a #10, the bond between rods "at the location" must be #6 minimum.

The code writers could do a much better job with article 250. It's a mess and hard to decipher. Especially for "multi-hat" inspectors who may not have an electrical background.
--
If someone refers to herself / himself as a "guru", they probably aren't.



Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

nunya it does not matter what the code says it's what the AHG says and without his sign-off the POCO will not reconnect the service.

Actually it's not a sub-panel but a 100 amp branch panel fed off the load side of the meter base in parallel with the line side of the house service panel.

People can argue the Code book all they want but it boils down to what the AHJ demands. Sure you can contest it but is it worth it? I'm just as safe so I really don't care.



John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:6

said by Jack_in_VA:

Actually it's not a sub-panel but a 100 amp branch panel fed off the load side of the meter base in parallel with the line side of the house service panel.

That's the difference right there...


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

said by John Galt:

said by Jack_in_VA:

Actually it's not a sub-panel but a 100 amp branch panel fed off the load side of the meter base in parallel with the line side of the house service panel.

That's the difference right there...

But the inspector also made the electrician install a parallel ground rod 5 ft from the original and tie the two together with (NOT ONE) but 2 #6 bare copper conductors. Go Figure.


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:6

said by Jack_in_VA:

Go Figure.

Like you said, what Lola wants, Lola gets.

kherr
Premium
join:2000-09-04
Collinsville, IL
Reviews:
·Charter
reply to nunya

said by nunya:

If you have any questions, call Bob the city inspector.

He don't have a clue. I seen in a commercial building that he inspected where the GC installed romex for the wiring with his own guys. Needless to say the GC's house that he was building for himself "mysteriously" burned to the ground one night at 3AM (the electricians in town were pissed about the wiring job his guys did at the office building). His brother had a ring side seat from across the lake at his house. It burned so hot and so fast that the steel beam in the basement didn't survive. It took the FD 4 tries till they found a hydrant that worked, not to mention that 2 of the trucks broke down on the way. The manufacturer of the heating equipment asked the HVAC guy if he could take some pictures of the furnace so they study it, there was nothing left. This town makes the Three Stooges look like the McCarthy Bros. (a St.Louis based worl wide construction co.).

I built an add-on to my garage a few years ago, and when I asked at what stage I needed inspections they said there weren't any. Just about anything goes here, they just want the permit $$$. At the time I built my garage, I didn't know that the neutrals and grounds were separated in a sub-panel .... neither did he. After seeing that you do on this forum, I separated them. I just want to make things right. I've seen bare ground wires left open all the time in the inside. But that doesn't make it right or wrong. It's definitely going to have conduit outside.


whizkid3
Premium,MVM
join:2002-02-21
Queens, NY
kudos:9
reply to nunya

said by nunya:

Your inspector was wrong and the electrician was right. At an outbuilding with a feeder other than a branch circuit (E.G. sub-panel) then a grounding electrode is required (doesn't have to be a ground rod, but that's typically the defacto choice). ...

Nunya is on the money here. And from what one can see with even his 'simplified' explanation, is that it is a very complex subject that is best left to the pros. And often, many of them get it wrong as well.

Yeah, if the AHJ demands something and you are not a PE or licensed master electrician; you are basically going to have little other recourse but to follow their wishes. Often, even when you are a PE or master electrician - you may still want to follow their (incorrect) wishes, unless its a large monetary hit or other substantial reason to disagree.

quote:
But the inspector also made the electrician install a parallel ground rod 5 ft from the original and tie the two together with (NOT ONE) but 2 #6 bare copper conductors. Go Figure.
WTF? Obviously from a carpentry background.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

1 recommendation

said by whizkid3:

said by nunya:

Your inspector was wrong and the electrician was right. At an outbuilding with a feeder other than a branch circuit (E.G. sub-panel) then a grounding electrode is required (doesn't have to be a ground rod, but that's typically the defacto choice). ...

Nunya is on the money here. And from what one can see with even his 'simplified' explanation, is that it is a very complex subject that is best left to the pros. And often, many of them get it wrong as well.

Yeah, if the AHJ demands something and you are not a PE or licensed master electrician; you are basically going to have little other recourse but to follow their wishes. Often, even when you are a PE or master electrician - you may still want to follow their (incorrect) wishes, unless its a large monetary hit or other substantial reason to disagree.

quote:
But the inspector also made the electrician install a parallel ground rod 5 ft from the original and tie the two together with (NOT ONE) but 2 #6 bare copper conductors. Go Figure.
WTF? Obviously from a carpentry background.

Whiz I'm in a one-man AHJ operation county here. That may explain it. He retired and now we have a retired Fire Department Inspector (whatever that is). I haven't had any dealings with him.