# ground wire in EMT



## 480sparky (Sep 20, 2007)

If it's not a job spec, it's a design choice.


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## NolaTigaBait (Oct 19, 2008)

danickstr said:


> good practice? waste of wire?


Good practice...waste of money if I'm contracting the job:laughing:


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## bobelectric (Feb 24, 2007)

Standard Practice.


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## 220/221 (Sep 25, 2007)

Required here since some time in the 80's.

I didn't know it wasn't an NEC requirement until the intenets.

I think it's good practice. We've all seen couplings/connectors come loose.


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## Speedy Petey (Jan 10, 2007)

bobelectric said:


> Standard Practice.


Agree. I'll do it no other way.


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## Speedy Petey (Jan 10, 2007)

Damn. Five replies in four minutes. 
This site is good!


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## leland (Dec 28, 2007)

Speedy Petey said:


> Damn. Five replies in four minutes.
> This site is good!



Partly your fault.:thumbsup:


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## bobelectric (Feb 24, 2007)

Sometimes!


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## danickstr (Mar 21, 2010)

The buildin owner's regular EC looked mildly disapprovingly at me for pulling it today. I figure if there's room in the pull, I pull it. If there isn't room, then it needs one even worse 

There was a conduit when I got to the job with a blue wire in it, and a knocked out coupler. Turns out it was 277, so it was rubbing on IMO mismarked wire without a ground.

I like to pull 'em.


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## subelect (Nov 25, 2007)

I was going to ask this question today in fact.
The boss loves to use EMT as the EGC; I would rather pull a ground wire. 
So, if I am by myself, I always use a ground wire. If the boss is there, we use EMT.

On a similar note, what size conductor in the EMT do you no longer feel safe using EMT as the sole EGC? Is it a length of conductor/EMT or is it a certain gage wire?
Rick


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## william1978 (Sep 21, 2008)

Standard practice.


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## bobelectric (Feb 24, 2007)

Let"s hear from the boys in Chicago.


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## Vintage Sounds (Oct 23, 2009)

Not optional.


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## danickstr (Mar 21, 2010)

Regarding feeling safe, 15 amps can sure kill quick under the wrong circumstances, so I don't feel safe at any gauge without it. 

I wonder if anyone has failed due to pulling too small an EGC, even though it was in EMT.


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## NolaTigaBait (Oct 19, 2008)

I was retrofitting some strip lights today that were put in '90...I check the set screws for the hell of it-every one was loose!...They never stay tight...I still don;t run a ground...what an idiot:blink:


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## BuzzKill (Oct 27, 2008)

Speedy Petey said:


> Agree. I'll do it no other way.


Ditto, over build.


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## Article 90.1 (Feb 14, 2009)

Run the EGC so the next guy has something to pull another circuit in in the future. :thumbsup:


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## danickstr (Mar 21, 2010)

Article 90.1 said:


> Run the EGC so the next guy has something to pull another circuit in in the future. :thumbsup:



That was actually my line today.


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## 480sparky (Sep 20, 2007)

220/221 said:


> ......... We've all seen couplings/connectors come loose.


NNNNNOOOOOOOOOOoooooooooooooooooooo!

Never happens!

:laughing:


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## HackSmasher (Mar 11, 2010)

Starting out in the trade, I thought it was mandatory since my boss always pulls in a bond for EMT, regardless of the job. Not mandatory, but good practice. I once had an emergency call where a 200a switch let go and blew out a 1000a fuse in an apartment. There was no bonding conductor in the conduit, and what a mess it made of the pipe.


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## Buddha In Babylon (Mar 23, 2009)

Yeah no doubt, I think it's the smartest way to do things. Using EMT as an EGC is one of those things that if I install all the pipe and know how i installed it, I am ok with the idea, but if i come up on it in the field, i always have my doubts as to it's integrity. It's not that i don't trust other peoples work, it's that i've been made a fool of more than once by giving some radom ock, the benefit of the doubt.:001_unsure:


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## 10492 (Jan 4, 2010)

Standard practice.

I've seen way too many pieces of emt yanked off walls, die cast couplings smashed, to not run one.


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## Buddha In Babylon (Mar 23, 2009)

Hey Dnkldorf, where in PA are you from? I grew up in the Franklin County area. Real close to Hagerstown MD.


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## yucan2 (Jun 9, 2009)

bobelectric said:


> Let"s hear from the boys in Chicago.


Last few years, especially larger projects, almost all specs are mandating pulling ground in conduit.

Slowly becoming 2nd nature. Specs. or not. 

What I see happening though is someone will say oops, you didn't pull a ground. Response, Check the specs. It's not there. Oh, ok, lets move on.


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## Dennis Alwon (May 9, 2009)

Truth be told the emt is a much better ground then any wire sized by 250.66. Of course, the install is always a potential problem. I would almost bet you could run a 100 feet of emt and not tighten one connector and you would still have some continuity at the end.

Apparently this is not as big a problem as we think, otherwise the NEC would have changed the rule by now.

I always pull an EGC


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## sparks134 (Jan 30, 2009)

Dennis Alwon said:


> Truth be told the emt is a much better ground then any wire sized by 250.66. Of course, the install is always a potential problem. I would almost bet you could run a 100 feet of emt and not tighten one connector and you would still have some continuity at the end.
> 
> Apparently this is not as big a problem as we think, otherwise the NEC would have changed the rule by now.
> 
> I always pull an EGC


 Don't you mean table 250.122 min. EGC for grounding raceway and equipment?:001_unsure:


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## NolaTigaBait (Oct 19, 2008)

sparks134 said:


> Don't you mean table 250.122 min. EGC for grounding raceway and equipment?:001_unsure:


Watch your mouth, boy!....Don't ever question Dennis.:thumbsup:


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## Dennis Alwon (May 9, 2009)

sparks134 said:


> Don't you mean table 250.122 min. EGC for grounding raceway and equipment?:001_unsure:


Yes-- thanks.


NolaTigaBait said:


> Watch your mouth, boy!....Don't ever question Dennis.:thumbsup:


Yeah, I thought I made a mistake once but was wrong.


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## sparks134 (Jan 30, 2009)

no problem!


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## david wise (Feb 17, 2010)

Always pull a ground. I worked with one guy who pulled a ground for every circuit in the pipe until I straightened him out. Now that's a waist of wire (money).


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## sparks134 (Jan 30, 2009)

david wise said:


> Always pull a ground. I worked with one guy who pulled a ground for every circuit in the pipe until I straightened him out. Now that's a waist of wire (money).


It is a waste of money! >>>>>Tell him to look at 
Multiple Circuits 250.122 (C)


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## John Valdes (May 17, 2007)

SOP Here.


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## william1978 (Sep 21, 2008)

david wise said:


> ...... I worked with one guy who pulled a ground for every circuit in the pipe until I straightened him out. Now that's a waist of wire (money).


 What was his reason for this. Man that sounds like a ton of extra work and money.


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## Innovative (Jan 26, 2010)

Went to a UL bonding and grounding seminar..... 8 boring hours... but they did say tests show that a 3/4" emt, when properly installed, was more effective than even a #6 thhn ground wire, it tripped the breaker in 60% less time. But the key is, "when properly installed".


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## william1978 (Sep 21, 2008)

Innovative said:


> . But the key is, "when properly installed".


:yes: Did they say anything about how that conduit will work in time after the building has settled and vibrations and so on?


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## Innovative (Jan 26, 2010)

I asked that same question and they kinda skirted the issue......I always pull a ground wire, always have. They had a big discussion that if you do pull it, it must be sized accordingly. They dont care that it is redundant. We had a case one time on a 2000a parallel service where we screwed up(actually, the engineer who drew the service, but I should have checked it) the ground wire sizing 1 size. The pull was a real nightmare and removing the ground and repulling it was not an option. We actually disconnected the ground, removed the green tape(as the inspector suggested) and then re-installed it after the job was complete. The conduit was RMC, but I still wanted the ground wire....... Yes, it was a code violation, but a violation that I feel made the job safer.


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## Useless Troll (Apr 16, 2010)

480sparky said:


> If it's not a job spec, it's a design choice.


I agree. I don't believe in a "one size fits all approach" to an issue like this. 
Is it really necessary to run separate EGC's in EMT that is part of a strut rack in a metal trussed or framed building? In my opinion, no. 

As for the workmanship issue of couplings and connectors being left loose or loosening over time, the same could be applied to cable wiring methods and PVC. Do you run 2 ground wires in PVC conduit? Do your run isolated ground MC cable just in case? Do you tape an additional ground wire to the jacket of romex? In all those cases above, a single point failure of a loose wirenut or terminal could leave an entire circuit without an EGC, in the same manner that a loose EMT fitting could compromise the EGC. So bad workmanship is no reason not to rely on a superior grounding path the EMT raceway provides. IMO of course.


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## Useless Troll (Apr 16, 2010)

william1978 said:


> :yes: Did they say anything about how that conduit will work in time after the building has settled and vibrations and so on?


:001_huh: A building has to settle and shake an awful lot for EMT fitting to come loose. Sock your setcrews and locknuts down tight and they'll be good for the next hundred years. :thumbsup:


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## cdnelectrician (Mar 14, 2008)

Well, think about this scenario: You have a good quality square D panel with lots of nice thick electric grey paint on the tub, around the KO. And into that KO you have a cheap die cast chinese EMT connector with an even crappier locknut. Please tell me HOW that makes for a good bond? I always pull an EGC in my conduits.


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## Useless Troll (Apr 16, 2010)

cdnelectrician said:


> Well, think about this scenario: You have a good quality square D panel with lots of nice thick electric grey paint on the tub, around the KO. And into that KO you have a cheap die cast chinese EMT connector with an even crappier locknut. Please tell me HOW that makes for a good bond? I always pull an EGC in my conduits.


The NEC requires us to remove the paint, plain and simple. And by the way, you have to do that even when you run a redundant EGC. 

I prefer steel fittings myself, but am not averse to relying on die cast fittings for a ground path. It's been done for generations and I certainly am not smarter than those who write the NEC, so I trust in its allowance to use the EMT as a ground path.


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## cdnelectrician (Mar 14, 2008)

Useless Troll said:


> The NEC requires us to remove the paint, plain and simple. And by the way, you have to do that even when you run a redundant EGC.
> 
> I prefer steel fittings myself, but am not averse to relying on die cast fittings for a ground path. It's been done for generations and I certainly am not smarter than those who write the NEC, so I trust in its allowance to use the EMT as a ground path.


I see what you are saying, but I have NEVER seen a guy remove paint from an enclosure before terminating a conduit into it. If they made it a rule to install an EGC that would get enforced a lot more than the latter.

I too prefer steel, but I use whatever is supplied to me unless I am doing the ordering.


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## Useless Troll (Apr 16, 2010)

For the record, I'm not saying I never run a wire EGC in EMT. When I run the EMT myself I can confidently omit the EGC, or if I can check the integrity of the existing raceway I'll also omit it. 

I guess my issue is when people condemn a particular way of doing things out of hand simply because of bad workmanship of installers.


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## cdnelectrician (Mar 14, 2008)

Useless Troll said:


> For the record, I'm not saying I never run a wire EGC in EMT. When I run the EMT myself I can confidently omit the EGC, or if I can check the integrity of the existing raceway I'll also omit it.
> 
> I guess my issue is when people condemn a particular way of doing things out of hand simply because of bad workmanship of installers.


Well, unfortunately a lot of conduit work I see really should have an EGC installed because it sucks! There are some really talented guys out there who know how to run conduit and then there are some who should go back to resi and leave their benders at the shop lol. The other problem I have with using EMT as an EGC is concentric KO's...


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## Useless Troll (Apr 16, 2010)

cdnelectrician said:


> Well, unfortunately a lot of conduit work I see really should have an EGC installed because it sucks! There are some really talented guys out there who know how to run conduit and then there are some who should go back to resi and leave their benders at the shop lol.


I think it's a wise practice to require redundant EGC's if you have to rely on questionable labor.


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## cdnelectrician (Mar 14, 2008)

Useless Troll said:


> I think it's a wise practice to require redundant EGC's if you have to rely on questionable labor.


 
Well no matter how it gets done, it can get screwed up...to each their own!


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## hiamp (Mar 14, 2010)

I've been pulling a ground through EMT since a guy touching 2 different machines in a machine shop was knocked across the room. The the gaps in the conduits couplings were filled with crud and many of them were loose or the set screw was missing. Most of the circuits were ungrounded in just that one 3/4 pipe run. Of course the owner had me pull a ground conductor through all the conduits and ground everything. I walked away knowing that shop was safer and have been pulling a ground conductor ever since.


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## Wingnut (Jan 31, 2010)

law here


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## david wise (Feb 17, 2010)

I feel that I'm pretty good with a bender in my hand and I know that I tighten all my conn. and coups ... but I have always ran a green conductor in every conduit I have ever installed...it's just the way I was taught


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## ggunn (Mar 15, 2010)

Useless Troll said:


> :001_huh: A building has to settle and shake an awful lot for EMT fitting to come loose. Sock your setcrews and locknuts down tight and they'll be good for the next hundred years. :thumbsup:


Not necessarily. If your conduit is subjected to wide swings in temperature, those set screw points are going to move. If you have telescoping expansion joints, crud can get between the moving metal parts.


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## kancerr (Apr 16, 2010)

if its not required, hospitals, schools, govt...dont do it here, waste of money, put your pipe and boxes together correctly shouldnt have any issues with grounding...i had a job that was gone in all mc, and all pipes had ground wire pulled thru, a condo complex, asked boss for ground wire for my emt run and he laughed at me, said no. so never use it here unless required.


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## Bob Badger (Apr 19, 2009)

For what it is worth the NFPA considers the conduit the primary EGC and the wire EGC a back up to that in hospital applications.

It is also worth pointing out that the steel conduit will often have less impedance than any wire EGC you pull inside it.


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## Trust (Apr 17, 2010)

Ground wire in every single run. Not having it can come back and bite you in the ass if the inspector decides that it's required.


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## 480sparky (Sep 20, 2007)

Trust said:


> Ground wire in every single run. Not having it can come back and bite you in the ass if the inspector decides that it's required.



The inspector had better have a Code reference to back him/her up.


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## fraydo (Mar 30, 2009)

I always run one but only in the work I do. If I extend an old install that doesn't have one I'll just terminate that end to the box.Even if it's redundant it's also nice to have it in case you need to pull additional wires later.


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## Trust (Apr 17, 2010)

480sparky said:


> The inspector had better have a Code reference to back him/her up.


That's true but then it opens up a whole new can of worms when the inspector starts questioning the integrity of your pipe runs. I think between the time and the effort of pulling in the ground it's 100% worth it. Also it's almost always spec'd anyways.


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## 480sparky (Sep 20, 2007)

Trust said:


> That's true but then it opens up a whole new can of worms when the inspector starts questioning the integrity of your pipe runs. I think between the time and the effort of pulling in the ground it's 100% worth it. Also it's almost always spec'd anyways.



Then you set a precedent..... you'll fold as soon as the inspector pulls a 'code' out of his ass.

He is an *in*spector, not an *ex*pector.


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## Bob Badger (Apr 19, 2009)

Trust said:


> Ground wire in every single run. Not having it can come back and bite you in the ass *if the inspector decides that it's required.*


That is when you explain to the inspector that you work under the NEC and not under the inspectors personal desires.


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## piperunner (Aug 22, 2009)

I must say that the nec is great for minimum standard regulations , but to me its what type of work one does yes they say conduit is a better ground but it can come apart and not from shotty work but from other trades or accidents in the field .

If one had a large electrical company with lots of jobs going and one day after jobs done new owners move in and a person gets shocked or even killed by say a non ground issue .

There goes your money saved on that ground wire not needed because the code said its ok .

Or maybe you do small work and dont run 150,000 feet of branch conduits every job so you can say we do it right everyday and feel its ok because you just need to check two pipes in the ceiling but i think a ground is a good way to bond it .

We do it for insurance the cost is well worth not !:yes:


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## Bob Badger (Apr 19, 2009)

So piperunner a couple of questions.

Have you never seen a bad splice on an EGC?

Do you run redundant EGCs when you run PVC or NM?


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## william1978 (Sep 21, 2008)

Grounding is highly overrated.


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## piperunner (Aug 22, 2009)

Bob Badger said:


> So piperunner a couple of questions.
> 
> Have you never seen a bad splice on an EGC?
> 
> Do you run redundant EGCs when you run PVC or NM?



Yes

We run mostly conduit pvc and emt some in wall NM but mostly conduit yes we install a ground in every run .

Its a company rule do to a accident years ago .


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## drsparky (Nov 13, 2008)

william1978 said:


> Grounding is highly overrated.


 In the world of turning on 60 watt light bulbs maybe. When your are working with very small voltages that are referenced to ground you need quality power and quality grounds. A normal Motorola hand held radio must test down to .0000003 volts (.3 micro volts)
If their is noise on the ground it throws off our tests. Yes isolated grounds do help.


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## 220/221 (Sep 25, 2007)

> Grounding is highly overrated


I had a guy working for me for a very brief period many years ago that used those exact words. :jester:

We still quote him on occaision.

I think the NEC should require EGC's everywhere.


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## 480sparky (Sep 20, 2007)

220/221 said:


> ...........I think the NEC should require EGC's everywhere.


EMT _is_ an EGC. 250.118(4)


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## Bob Badger (Apr 19, 2009)

220/221 said:


> I think the NEC should require EGC's everywhere.


It already does. :yes:


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## 480sparky (Sep 20, 2007)

Bob Badger said:


> It already does. :yes:



I think he wants a _wire_.


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## Bob Badger (Apr 19, 2009)

piperunner said:


> We run mostly conduit pvc and emt some in wall NM but mostly conduit yes we install a ground in every run .


Of course you run an EGC with NM and PVC but do you run 2 EGCs in case one fails?


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## Bob Badger (Apr 19, 2009)

480sparky said:


> I think he wants a _wire_.


Ya think? :jester:


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## jwjrw (Jan 14, 2010)

Bob Badger said:


> Of course you run an EGC with NM and PVC but do you run 2 EGCs in case one fails?


 

:no::no::laughing:


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## piperunner (Aug 22, 2009)

Bob Badger said:


> Of course you run an EGC with NM and PVC but do you run 2 EGCs in case one fails?



Good point Bob when i go to work monday ill tell the president of our company that we dont need to install a ground in a metal conduit that the raceway connection is good enough .

Ok question now your saying a conduit is a good connection and ground wire is not needed the conduit can handle the fault ?

Now can it handle more current than the nec size ground for that breaker size or the same amount of fault current for that breaker size ?

Next when a fault happens down stream can it go to a strap or part of the building when say a conduit gets damaged or a fault issue comes up ? meaning fault current running out in parallel condition and breaker doesnt trip fast enough .


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## MisterCMK (Jul 5, 2009)

Does anyone have a link to a study or white paper about using the conduit as the ground in comparison to running a separate EGC?


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## 480sparky (Sep 20, 2007)

MisterCMK said:


> Does anyone have a link to a study or white paper about using the conduit as the ground in comparison to running a separate EGC?



You mean like this? (Last paragraph of page 3)


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## piperunner (Aug 22, 2009)

Ok so if you dont run over 400 feet with your conduit you fine.

What if your 500 feet or more ?

And run thur a few pull boxes i didnt see aluminum conduit listed ?

We already have seen the testing conduit for grounding & fault test most conduit manufactures have a page for this so they can show there product is a good ground under test .

Did you know they only use a 2 inch length of emt conduit when they perform this test with no connectors and calculate by computer the results if it was longer in length under perfect conditions temp/ voltage / and fault in a lab .

Lets test at 500 feet or 600 feet rigid conduit or aluminum after one year or two in a industrial plant its impedance is not what it was when you installed it .

Example cutting oil and pipe dope on aluminum threads underground water rusting conduit its ok when new but we need to look at the nec its not correct in some areas its lacking .

They also need to include freq the thing called hertz.

We agree the NEC is a great book testing is great but there is a better way to ground conduit alone is a joke in my book.


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## McClary’s Electrical (Feb 21, 2009)

Useless Troll said:


> I agree. I don't believe in a "one size fits all approach" to an issue like this.
> Is it really necessary to run separate EGC's in EMT that is part of a strut rack in a metal trussed or framed building? In my opinion, no.
> 
> As for the workmanship issue of couplings and connectors being left loose or loosening over time, the same could be applied to cable wiring methods and PVC. Do you run 2 ground wires in PVC conduit? Do your run isolated ground MC cable just in case? Do you tape an additional ground wire to the jacket of romex? In all those cases above, a single point failure of a loose wirenut or terminal could leave an entire circuit without an EGC, in the same manner that a loose EMT fitting could compromise the EGC. So bad workmanship is no reason not to rely on a superior grounding path the EMT raceway provides. IMO of course.


 

These are my thoughts exactly. Aporoperly sized and installed pipe EGC, will ALWAYS be a better fault current path than the comparable, wire EGC from 250.122. Improper installation, or improper maintenance can leave either installation without a ground fault path. An extra wire is a waste of money, and I always omit it from the pull, unless it's job spec or somebodies paying for it.


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