Topic 'Bare ground need conduit ??' in forum 'Home Improvement' - dslreports.com

Re: Bare ground need conduit ??

Wed, 26 Dec 2012 08:35:36 EDT

laserfan posted :

I mean, just look at this thing (That's just 1 out of 12 pages).
»ecmweb.com/bonding-amp-grounding···art-1-12
It's a LOT of stuff to understand.

You ain't just whistlin' Dixie brother--I've only Skimmed it (not yet Studied it) and so far all I've gotten out of it is that you can't count on Earth Ground for a "return path", and (I think) also that while it Used To Be that a remote building didn't need a ground rod, now it is recommended to have a ground rod In Addition to a ground Conductor/Wire back to the service panel.

Gonna read it again (and again) but it does make my brain hurt... ;)

Re: Bare ground need conduit ??

Tue, 25 Dec 2012 08:18:15 EDT

laserfan posted :

said by alkizmo:

I'm not an electrician, but I'm pretty handy, yet when it comes to grounding, I still err on the side of caution and get validation from the pros.

I mean, just look at this thing (That's just 1 out of 12 pages).
»ecmweb.com/bonding-amp-grounding···art-1-12
It's a LOT of stuff to understand.

And I only "worked with" electricians and electrickery for some years, thus knowing just enough to be dangerous.

;)

What a great link, thanks; I have bookmarked it and will study thoroughly at another time when my brain is at 100%. Early Xmas morning here and I'm a little bleary-eyed.

Happy holidays everyone!

Re: Bare ground need conduit ??

Mon, 24 Dec 2012 09:15:16 EDT

alkizmo posted :

said by laserfan:

Yeah, but it's clear from this thread that there is no "correct" afaict.

Yes there is a "incorrect" because there IS a "correct" way to put in grounding electrodes.

If the military can ground their portable electrical equipment in the mountains, then I'm sure you can get a good ground in rocky soil in Texas.

You might not be able to get a ground rod in, but you could get several ground plates in there, or a ground grid. It just requires heavy machinery instead of a sledge hammer.

Then as Jack_in_VA said, it's also about properly bonding the electrodes together, which a weekend warrior who doesn't understand the difference between grounding and bonding might horribly screw up.

I'm not an electrician, but I'm pretty handy, yet when it comes to grounding, I still err on the side of caution and get validation from the pros.

I mean, just look at this thing (That's just 1 out of 12 pages).
»ecmweb.com/bonding-amp-grounding···art-1-12
It's a LOT of stuff to understand.

Re: Bare ground need conduit ??

Mon, 24 Dec 2012 07:48:58 EDT

laserfan posted : Yeah, but it's clear from this thread that there is no "correct" afaict.

;)

Re: Bare ground need conduit ??

Sun, 23 Dec 2012 07:51:32 EDT

Jack_in_VA posted :

said by laserfan:

said by leibold:

In case anybody is wondering, in many areas it is now required to have a minimum of two grounding electrodes (the buried water supply line is often counted as one of them)

In the TX countryside there are no metal water pipes underground, and the "soil" itself is mostly rock, such that it's difficult even to get a ground rod driven-in. There are wires alongside every power pole fwiw, that get buried with the pole--I suppose that's SOP everywhere.

So for all the controversy here about "to add a ground or not" I'm inclined to err on the side of "ground wherever you can".

Even if it sets up a very dangerous "difference of potential" by improper bonding of the grounds by some people installing them that really don't have the knowledge of what they are doing? The "more ground rods the better" is not necessarily correct.

Re: Bare ground need conduit ??

Sun, 23 Dec 2012 07:37:57 EDT

laserfan posted :

said by leibold:

In case anybody is wondering, in many areas it is now required to have a minimum of two grounding electrodes (the buried water supply line is often counted as one of them)

Re: Bare ground need conduit ??

Sat, 22 Dec 2012 12:54:19 EDT

leibold posted :

said by Jack_in_VA:

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.

He wasn't German by any chance ? It does sound like the German Engineering approach of precisely determining the safety requirements and then doubling everything anyway :-)

In case anybody is wondering, in many areas it is now required to have a minimum of two grounding electrodes (the buried water supply line is often counted as one of them) however the two ground rods Jack mentions only count as one since they are too close together (only 5ft apart).
--
Got some spare cpu cycles ? Join Team Helix or Team Starfire!

Re: Bare ground need conduit ??

Sat, 22 Dec 2012 11:52:08 EDT

laserfan posted :

said by alkizmo:

said by laserfan:

Well this has gotten complicated hasn't it. Since there are no "authorities" where I live

No actually it gets quite simple: Do what the NEC says to do (AKA Nunya/Whizkid).

Ha, ha! Good one!

Yes, in TX everyone is supposed to go by the NEC.

said by nunya:

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.

Re: Bare ground need conduit ??

Sat, 22 Dec 2012 11:50:05 EDT

nunya posted : Most states will adopt codes to cover areas not covered by a city or county ordinance.
Even if you live in the most remote part of Alaska, there's still a code requirement.
There may not be anyone available to enforce it, but you owe it to yourself to do it right (or have it done right).
Remember, code is the bare minimum. It's the least you can "get away with".
--
If someone refers to herself / himself as a "guru", they probably aren't.

Re: Bare ground need conduit ??

Sat, 22 Dec 2012 11:38:06 EDT

alkizmo posted :

said by laserfan:

Well this has gotten complicated hasn't it. Since there are no "authorities" where I live

No actually it gets quite simple: Do what the NEC says to do (AKA Nunya/Whizkid).

Re: Bare ground need conduit ??

Fri, 21 Dec 2012 18:04:56 EDT

laserfan posted : Well this has gotten complicated hasn't it. Since there are no "authorities" where I live (had to look-up AHJ and a couple other acronyms) I'm going with ground rods at all outbuilding panels, all tied together.

:p

Re: Bare ground need conduit ??

Fri, 21 Dec 2012 12:31:56 EDT

Jack_in_VA posted :

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.

Re: Bare ground need conduit ??

Fri, 21 Dec 2012 12:05:29 EDT

whizkid3 posted :

said by nunya:

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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 20:46:03 EDT

kherr posted :

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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 20:06:35 EDT

John Galt posted :

said by Jack_in_VA:

Go Figure.

Like you said, what Lola wants, Lola gets.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 20:02:15 EDT

Jack_in_VA posted :

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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 19:52:12 EDT

John Galt posted :

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...

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 16:59:15 EDT

Jack_in_VA posted : 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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 16:49:01 EDT

nunya posted : 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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 16:18:53 EDT

Jack_in_VA posted :

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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 16:10:27 EDT

LazMan posted : Then I too, shall wait for those in the know to englighten us... :D

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 16:05:18 EDT

John Galt posted :

said by LazMan:

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

Actually, it's none of those... ;)

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 16:03:40 EDT

LazMan posted :

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? ;)

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 15:59:46 EDT

John Galt posted :

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. ;)

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 15:33:40 EDT

cdru posted :

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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 12:43:16 EDT

laserfan posted : 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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 11:59:40 EDT

cableties posted :

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

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 11:08:34 EDT

Jack_in_VA posted :

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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 09:42:00 EDT

cdru posted :

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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 09:18:14 EDT

whizkid3 posted :

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.

Re: Bare ground need conduit ??

Thu, 20 Dec 2012 08:09:28 EDT

laserfan posted :

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.

Re: Bare ground need conduit ??

Wed, 19 Dec 2012 19:48:30 EDT

whizkid3 posted :

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.

Re: Bare ground need conduit ??

Wed, 19 Dec 2012 19:45:00 EDT

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

Re: Bare ground need conduit ??

Wed, 19 Dec 2012 18:49:25 EDT

laserfan posted :

said by kherr:

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...

Re: Bare ground need conduit ??

Wed, 19 Dec 2012 16:53:44 EDT

nunya posted : Rigid PVC is OK by code.

Re: Bare ground need conduit ??

Wed, 19 Dec 2012 16:46:46 EDT

ArgMeMatey posted :

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?

Re: Bare ground need conduit ??

Wed, 19 Dec 2012 16:30:27 EDT

nunya posted : 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.

Re: Bare ground need conduit ??

Wed, 19 Dec 2012 16:24:33 EDT

davidg posted : 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!

Re: Bare ground need conduit ??

Wed, 19 Dec 2012 12:38:58 EDT

alkizmo posted : 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.

Re: Bare ground need conduit ??

Wed, 19 Dec 2012 12:30:07 EDT

LazMan posted : 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.

Bare ground need conduit ??

Wed, 19 Dec 2012 12:19:10 EDT

kherr posted : 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??