# Bare Ground in EMT?



## raider1

So how would running a bare copper ground wire in a steel conduit be any different than attaching a copper EGC at a steel box?

There is no prohibition in the NEC to installing a bare copper EGC in a steel conduit.

Take a look at 250.118(1) this section specifically permits a bare copper conductor to be used as an EGC.

Chris


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## nakulak

so you can use a bond bushing to make sure that the conduit is bonded, but the bare copper isn't allowed ? wtf ?


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## Tiger

What is the conduit/circuit being used for?

Dave


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## Roger123

Safety-Guy said:


> It has recently been interpreted by an AHJ in FL that pulling bare copper ground wire in metal conduit is a code violation. We have asked for a code reference, but I suspect it will be 342.14 , 344.14, or 358.12(6).
> If anyone knows of any code reference that would contradict this ruling, please let me know your input.


I believe that the above stated sections have to do with dissimilar metals as related to aluminum and copper connected together which will cause a galvanic action not a copper ground wire coming in contact with metal conduit.

A bare EGC in conduit is a bit uncommon trade practice though.


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## Thomp

Roger123 said:


> I believe that the above stated sections have to do with dissimilar metals as related to aluminum and copper connected together which will cause a galvanic action not a copper ground wire coming in contact with metal conduit.
> 
> A bare EGC in conduit is a bit uncommon trade practice though.


 

This is true, we have to wrap our conduits if they come into to close of contact with copper plumbing pipes.


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## leland

we have them wrap the copper.

is it al conduit?


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## Greg

Which county did this, Orange or Seminole?


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## Safety-Guy

Greg said:


> Which county did this, Orange or Seminole?


Palm Beach County is where the site is.


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## Thomp

leland said:


> we have them wrap the copper.
> 
> is it al conduit?


Yeah, you can wrap either the copper or conduit as long as they don't touch.


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## Bkessler

I use bare copper in conduits all the time. Mostly to run to the ground rod when there is a house on a slab and I am doing a service change.


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## Thomp

Bkessler said:


> I use bare copper in conduits all the time. Mostly to run to the ground rod when there is a house on a slab and I am doing a service change.


I was taught not to do this because the conduit would act as a choke and inhibit the path to ground.


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## raider1

Thomp said:


> I was taught not to do this because the conduit would act as a choke and inhibit the path to ground.


If you bond both ends of the conduit to the GEC then you are OK. (See 250.64(E))

It is better to use a non-ferrous raceway to enclose the GEC such as schedule 80 PVC.

Chris


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## Thomp

It is better to use a non-ferrous raceway to enclose the GEC such as schedule 80 PVC
This seems like a better game plan to me.


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## Bkessler

maybe this is the way I will do it from now on with pvc.


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## raider1

Bkessler said:


> maybe this is the way I will do it from now on with pvc.


I always use PVC to run my GEC, it eliminates all of the problems with electromagnetic fields and the chock effect around the GEC.

Chris


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## RIVETER

*Bare ground wires*

I have gotten my butt ripped about power factor, so I am not afraid of this one. Someone in Florida is thinking that if you run a bare "Equipment grounding conductor" in EMT you are definitely creating a parallel path of fault current, if a fault current exists. The problem is when the (parallel path of fault current is interrupted by a BREAK, as a loose, or non existent tight coupling. Theoretically, at the point of the (LOST) connection in the conduit, an Inductive choke could be developed and an IMPEDENCE is set up as to restrict the FAULT CURRENT, and slowing the tripping of the overload device which would be measured in cycles per second. That is my story and I'm sticking to it.

RIVETER


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## Speedskater

RIVETER does the fault current cause this BREAK? Or was this BREAK a pre-existing condition?


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## RIVETER

*Fault current*

You are correct, the break is a pre- existing condition.
NOT THE FAULT.


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## brian john

RIVETER said:


> You are correct, the fault is a pre- existing condition.


 
So what happens when one the hack electricians leaves the copper connection loose? The argument some use of loose connections can be applied to any thing we do. I say if that is the quality of work you do or are use to sub it all out to professionals.


I can argue that all wiring should be in rigid for the same reason. A hack electrician improperly installs NM and nicks the insulation, better use rigid.

So the point is when properly installed there is no issue, if you cannot properly install it hang drywall.


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## macmikeman

The code addresses bonding both ends of metal conduit containing the grounding electrode conductor not equipment grounds. It don't make a single bit of difference if that wire is insulated or not. As far as having to have insulation on equipment grounding wires in conduit, there is no code about it and I bet no UL listing issue either. (I am going to check on that, I'll get back to you).


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## macmikeman

Ok I'm back. All clear on the UL white book front- no mention of any requirements to have to use insulated wire for equipment grounding in aluminum conduits rigid or emt. Power trip.:whistling2:


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## pjmurph2002

"So the point is when properly installed there is no issue, *if you cannot properly install it hang drywall.”*

Exactly!!


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## macmikeman

pjmurph2002 said:


> "So the point is when properly installed there is no issue, *if you cannot properly install it hang drywall.”*
> 
> Exactly!!



And a note for the original Florida 'AHJ" subject of this thread -
* if you cannot properly interpret it, change your title to " Idiot having jurisdiction", and hang drywall.”*[/FONT][/COLOR]


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## jdomain

brian john said:


> So what happens when one the hack electricians leaves the copper connection loose? The argument some use of loose connections can be applied to any thing we do. I say if that is the quality of work you do or are use to sub it all out to professionals.
> 
> 
> I can argue that all wiring should be in rigid for the same reason. A hack electrician improperly installs NM and nicks the insulation, better use rigid.
> 
> So the point is when properly installed there is no issue, if you cannot properly install it hang drywall.


I dig it Bro. Can't do it right? I got a ditch need diggin'...


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## McClary’s Electrical

jdomain said:


> I dig it Bro. Can't do it right? I got a ditch need diggin'...


 

Is this english?:whistling2:


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## RIVETER

*Bonding/grounding*



raider1 said:


> If you bond both ends of the conduit to the GEC then you are OK. (See 250.64(E))
> 
> It is better to use a non-ferrous raceway to enclose the GEC such as schedule 80 PVC.
> 
> Chris


I agree here, it would be better to use a non-ferrous conduit, but conduit, if used, must have the appropriate BONDING devices at both ends to prevent the possibility of an INDUCTIVE CHOKE being set up, which, as I understand, could, possibly IMPEDE the flow of FAULT current...the overload device would take longer to trip.


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## te12co2w

Is it a mobile home? If so, then 550-33 applies.


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## raider1

RIVETER said:


> I agree here, it would be better to use a non-ferrous conduit, but conduit, if used, must have the appropriate BONDING devices at both ends to prevent the possibility of an INDUCTIVE CHOKE being set up, which, as I understand, could, possibly IMPEDE the flow of FAULT current...*the overload device would take longer to trip.*


The grounding electrode and the grounding electrode conductor do not have anything to do with actuating an overcurrent device.

You are correct that if you don't bond both ends of a GEC to a ferrous metal enclosure that you can ge an inductive choke effect. But this occurs when lightning current flows through the grounding electrode system to the earth. The choke effect can cause the lightning induced currents in the electrical system to try to find other paths into the earth rendering the grounding electrode system useless.

Chris


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## John Valdes

Thomp said:


> I was taught not to do this because the conduit would act as a choke and inhibit the path to ground.


I was told that too when I was an apprentice and did not know any better. It may have some merit theoretically, but it is allowed and a common way to install the GEC.


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## BigCL

So would Sch. 80 PVC or IMC be a better way to get the Ground Electrode Conductor/ Ufer to the 3rd floor 17kv substation?


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## raider1

BigCL said:


> So would Sch. 80 PVC or IMC be a better way to get the Ground Electrode Conductor/ Ufer to the 3rd floor 17kv substation?


IMHO, Sch 80 PVC would be the way to go.

Chris


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## nolabama

mcclary's electrical said:


> Is this english?:whistling2:


I dig it Bro. Can't do it right? I got a ditch need diggin'... 

please allow me to interpret this from ******* - a language that im fluent in to regular english

i dig it bro - means he understands the previous posters comment

cant do it right - means - if your a hack 

i got a ditch need diggin' -means- sir might i suggest a general labor job for you :thumbup:


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## jdomain

nolabama said:


> I dig it Bro. Can't do it right? I got a ditch need diggin'...
> 
> please allow me to interpret this from ******* - a language that im fluent in to regular english
> 
> i dig it bro - means he understands the previous posters comment
> 
> cant do it right - means - if your a hack
> 
> i got a ditch need diggin' -means- sir might i suggest a general labor job for you :thumbup:


precisely


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## Dave_E

RIVETER said:


> *Bare ground wires*
> 
> I have gotten my butt ripped about power factor, so I am not afraid of this one. Someone in Florida is thinking that if you run a bare "Equipment grounding conductor" in EMT you are definitely creating a parallel path of fault current, if a fault current exists. The problem is when the (parallel path of fault current is interrupted by a BREAK, as a loose, or non existent tight coupling. Theoretically, at the point of the (LOST) connection in the conduit, an Inductive choke could be developed and an IMPEDENCE is set up as to restrict the FAULT CURRENT, and slowing the tripping of the overload device which would be measured in cycles per second. That is my story and I'm sticking to it.
> 
> RIVETER


Does this mean I should NOT ground metal boxes in an EMT job?


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## Service Call

Almost 11 years. That’s the oldest resurrection I’ve seen yet.


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## just the cowboy

Service Call said:


> Almost 11 years. That’s the oldest resurrection I’ve seen yet.


Only a few posters left from that post.


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## macmikeman

I had the same username all these years. Was Cool Will McClary? I remember McClary pretty well.


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