250.118 - using emt conduit as a ground

difowler1

Senior Member
Looks like it's okay in 250.118 to use emt as a ground. Is it also code to run subpanel feeder circuit without a equipment grounding conductor as long as the wires are within emt pipe the whole way?
 

packersparky

Senior Member
To add to Roger's response, many studies have shown that a metallic raceway performs better at clearing a fault than a wire type equipment grounding conductor.
 

infinity

Moderator
Staff member
We use EMT as an EGC all of the time unless someone is paying for a wire type EGC in the raceway.
 

peter d

Senior Member
We use EMT as an EGC all of the time unless someone is paying for a wire type EGC in the raceway.
:thumbsup:

I don't get the obsession with wire EGC's. I always encounter EMT installations done from the 1960's to the 1980's and it never had a separate ground wire. Now it does. :roll:
 

MAC702

Senior Member
just seems weird, but ok. thanks
It did to me, too, because all my apprenticeship years were for places that spec'd the wire EGC, so it was normal for me. Now, people pay me to just make it work, and I'm the one buying and pulling the wire, so....
 

kwired

Electron manager
:thumbsup:

I don't get the obsession with wire EGC's. I always encounter EMT installations done from the 1960's to the 1980's and it never had a separate ground wire. Now it does. :roll:
Seen many from the time period you mentioned with poorly supported raceway contributing to broken fittings resulting in loss of EGC, also seen loose set screws or compression nuts, but that is all workmanship issues more than anything IMO. Have seen poorly made up EGC's in cable wiring methods as well - open continuity is still open continuity.

I do a lot of grain storage bins and handling equipment. Generally all steel structures and equipment. I do run EGC's in flexible conduits or in any non metallic raceways (which is usually just underground raceways in these applications) but see running any wire EGC in most of said systems as pointless, the equipment/structures are very effective fault return path, and usually more effective than my raceways, so if a fitting didn't get tightened it doesn't really matter much from equipment grounding perspective.
 

jap

Senior Member
Pulling a wire type EGC is more about a backup or assured bonding.

Much like a safety chain installed on a perfectly supported pendant fixture.

JAP>
 

jap

Senior Member
Plus, dropping that one conductor when emt is used, helps somewhat for the added conductors we now have to add for MWBC's that we didn't used to have to install.

That is for us old dogs that always used MWBC's and now don't like tying individual circuit handles together. :p

JAP>
 

kwired

Electron manager
Pulling a wire type EGC is more about a backup or assured bonding.

Much like a safety chain installed on a perfectly supported pendant fixture.

JAP>
Which NEC only requires additional paths for certain art 517 applications (could be other specific sections but am not aware of any), outside of that it is a design decision.
 

infinity

Moderator
Staff member
Which NEC only requires additional paths for certain art 517 applications (could be other specific sections but am not aware of any), outside of that it is a design decision.
If the raceway is so good as an EGC why is there ever a need for redundant grounding? Needs to be extra good? :)
 

kwired

Electron manager
If the raceway is so good as an EGC why is there ever a need for redundant grounding? Needs to be extra good? :)
I didn't write the rule, apparently it knows when it is in a health care facility and gets nervous or something:)
 

Besoeker3

Senior Member
Haven't seen EMT used for any installations since I was doing my apprenticeship in the 1840s....and even then we had to run a separate earth (grounding) conductor... :cool:
 

kec

Member
Seen many from the time period you mentioned with poorly supported raceway contributing to broken fittings resulting in loss of EGC, also seen loose set screws or compression nuts, but that is all workmanship issues more than anything IMO. Have seen poorly made up EGC's in cable wiring methods as well - open continuity is still open continuity.

I do a lot of grain storage bins and handling equipment. Generally all steel structures and equipment. I do run EGC's in flexible conduits or in any non metallic raceways (which is usually just underground raceways in these applications) but see running any wire EGC in most of said systems as pointless, the equipment/structures are very effective fault return path, and usually more effective than my raceways, so if a fitting didn't get tightened it doesn't really matter much from equipment grounding perspective.
Agree, if set screws are tight then your are good to go, but Ive come across installations [done by others] with duck tape used for couplings. :eek:hmy:
 

kwired

Electron manager
Agree, if set screws are tight then your are good to go, but Ive come across installations [done by others] with duck tape used for couplings. :eek:hmy:
And also seen 1/2 FMC fittings used for 3/4 EMT. Works great when you ran 3/4 but didn't know how to enlarge a 1/2 KO, or if you needed a 90 degree connector:blink:
 

LarryFine

Master Electrician Electric Contractor Richmond VA
. . . Ive come across installations [done by others] with duck tape used for couplings. :eek:hmy:
I'm sure the duct tape was put on to facilitate using vacuum to pull in string to pull in a pull rope.
 

DBoone

Senior Member
Agree, if set screws are tight then your are good to go, but Ive come across installations [done by others] with duck tape used for couplings. :eek:hmy:

Always use aluminum foil duct tape, maintains continuity....good to go
 

Adamjamma

Senior Member
It comes down to installation... in UK and USA I don’t run into much rusted out emt, so the use of it for ground is fine. In Caribbean I run into a lot of rusted out emt with no continuity of ground... so in Caribbean I always add a ground conductor...
 

petersonra

Senior Member
It comes down to installation... in UK and USA I don’t run into much rusted out emt, so the use of it for ground is fine. In Caribbean I run into a lot of rusted out emt with no continuity of ground... so in Caribbean I always add a ground conductor...
It seems to me that if the EMT is rusting out it is not suitable to use it at all in that location.
 

kwired

Electron manager
Used to be it was used in concrete... now pvc conduit more common. But, emt is still allowed in concrete as I recall.
PVC preferred in slab on grade or in walls below grade. Above grade I don't think matters much most cases unless corrosive agents are involved in the general area.
 

hornetd

Senior Member
If the raceway is so good as an EGC why is there ever a need for redundant grounding? Needs to be extra good? :)
In rooftop applications it is specified to overcome the possibility; some would say likelihood; that the connections of the steel EMT will corrode open.
 

hornetd

Senior Member
Agree, if set screws are tight then your are good to go, but Ive come across installations [done by others] with duck tape used for couplings. :eek:hmy:
Are you having us on? I've seen a lot of duct tape used to render fittings concrete tight.
 

480sparky

Senior Member
In rooftop applications it is specified to overcome the possibility; some would say likelihood; that the connections of the steel EMT will corrode open.
Why would someone specify the need for a grounding conductor..... when they could specify a raceway fitting that won't corrode away?
 

hornetd

Senior Member
Project manager! Need I say more?

Project manager! Need I say more?

Why would someone specify the need for a grounding conductor..... when they could specify a raceway fitting that won't corrode away?
Because it's cheaper. Why Else? They specify compression couplings but many of those are not evan listed as rain-tight. And then for good measure they specify aluminum boxes to throw dissimilar metals into the mix. I've actually have seen one aluminum EMT job with all compatible fittings and boxes but that was on the roof of a a Biotechnology Laboratory.

But why am I complaining about this stuff when I have had an inspector say he preferred plastic boxes for their additional inside volume used with EMT in a Fire Alarm System. Before you ask they were not the ones with the bonding strap inside the box to bond all of the KOs to each other. That same inspector approved a Fire Pump Controller with no neutral conductor back to the Wye connected utility transformer. But I was just an Electrician on that job and the project manager thought that the foreman was a hero for all of the money he saved.
 

kwired

Electron manager
In rooftop applications it is specified to overcome the possibility; some would say likelihood; that the connections of the steel EMT will corrode open.
Design decision, not a code requirement. Just as much design decision as one could run stainless or brass conduit and probably have little or no corrosion troubles, but would definitely be more expensive.
 

kec

Member
Are you having us on? I've seen a lot of duct tape used to render fittings concrete tight.
No, I get using tape to facilitate helping vacuum or making fittings tight and have used this method but what I was saying is I came across duck tape used as the coupling only
 

Strathead

Senior Member
Well, I will admit that I prefer a grounding conductor in EMT. I very rarely see a job that has ANY engineer's input that doesn't require a ground, and if I were an inspector, I would obviously not require ground, but I would make it more difficult for the installer by always insisting on spot checking the tightness of connectors and couplings during rough in inspections. this would include making sure a lift was available for coupling way up high. These are the ones I see as most often left loose. Find one, fail the job. While I consider myself a conscientious worker, I know that I have accidentally left couplings loose, or only tightened a compression fitting with one wrench. I understand the arguments in the other direction and I am not implying that those who take the no ground position are wrong just that I believe installations are better off with a separated grounding wire.
 

kwired

Electron manager
Well, I will admit that I prefer a grounding conductor in EMT. I very rarely see a job that has ANY engineer's input that doesn't require a ground, and if I were an inspector, I would obviously not require ground, but I would make it more difficult for the installer by always insisting on spot checking the tightness of connectors and couplings during rough in inspections. this would include making sure a lift was available for coupling way up high. These are the ones I see as most often left loose. Find one, fail the job. While I consider myself a conscientious worker, I know that I have accidentally left couplings loose, or only tightened a compression fitting with one wrench. I understand the arguments in the other direction and I am not implying that those who take the no ground position are wrong just that I believe installations are better off with a separated grounding wire.
I might be ok with that, but if I didn't use a lift at install, I am not providing you with one. Say I crawled through rafters or was harnessed and supported by rope/cable when I installed it, I will hand you the harness and say "have at it";)
 

Strathead

Senior Member
I might be ok with that, but if I didn't use a lift at install, I am not providing you with one. Say I crawled through rafters or was harnessed and supported by rope/cable when I installed it, I will hand you the harness and say "have at it";)
I agree, but in the scope of long term work in a jurisdiction it would end up being the path of least resistance to just put a ground in. I have rolled over to an inspector on things a lot more heinous than this just because it was going to be the best bet in the long run.
 

jap

Senior Member
it would end up being the path of least resistance to just put a ground in.

There's no way to actually prove that.

Installing a wire type EGC holds the same issues as using the EMT conduit as a fault return path.

If the wire type EGC is not installed properly, and, bonded in all of the places that is should be, it's no better than EMT installed in the same manner.

For every inspector that needs to crawl through ever conduit run that's using the conduit as the EGC only to see if all the fittings are tight , that same inspector is going to have to go back and open every box after the install is complete to see that a wire type EGC was bonded properly at each and every location.

JAP>
 

garbo

Member
EMT as an EGC.

EMT as an EGC.

We use EMT as an EGC all of the time unless someone is paying for a wire type EGC in the raceway.
45 years ago we always used the EMT as an EGC. My old boss ran several hundred feet of 3/4" EMT using the EMT an EGC and quality steel fittings indoors. Less then a year later a fitting came loose and while my boss hand one hand on either conduits and pushing them together one of the 480 volt wires shorted out. He came close to be electrocuted. We investigated why the breaker did not clear this on the recently purchased used machine. Somebody had tied this circuit to a 400 amp circuit breaker . We now run copper ground wires in every conduit. Better safe then dead. I still do not use or trust the cheap die cast EMT fittings especially the junk made in India or China.
 

Strathead

Senior Member
There's no way to actually prove that.

Installing a wire type EGC holds the same issues as using the EMT conduit as a fault return path.

If the wire type EGC is not installed properly, and, bonded in all of the places that is should be, it's no better than EMT installed in the same manner.

For every inspector that needs to crawl through ever conduit run that's using the conduit as the EGC only to see if all the fittings are tight , that same inspector is going to have to go back and open every box after the install is complete to see that a wire type EGC was bonded properly at each and every location.

JAP>
No actual way to prove what? The inspector inspects what he wants to inspect within the direction of his boss (AHJ). As I stated, if I were an inspector, I would basically make it economical to install a ground wire in all conduits. Don't worry, I'm not and I never will be. I expect that irritates some who don't want to install a ground wire. That is fine with me.

I have had an inspector either require things or make things difficult many times where we just did whatever to satisfy and make life easier in the future. I am sure it is the same for you. I doubt any contractor would be able to stay in business if they made sure to only do code minimum and prove the inspector wrong at every opportunity.
 

jap

Senior Member
No actual way to prove what?
There's no way to prove that by simply installing a wire type EGC it will magically create a path of lesser resistance.

In the end, it all boils down to the caliber of the installing electrician.

The same Electrician that installs loose conduit runs, is going to be the same electrician that doesn't terminate the wire type EGC's correctly to make the scenario any better.

Yes, pipes may come apart for some unknown reason, just like wire type EGC can be pulled loose by a connection made up by a shoddy electrician.

In my career, we were always required to install a wire type EGC also, but, I can personally say, on any project I've ever been on, I could depend on either one to due their job if one or the other happened to fail.

JAP>
 

jap

Senior Member
45 years ago we always used the EMT as an EGC. My old boss ran several hundred feet of 3/4" EMT using the EMT an EGC and quality steel fittings indoors. Less then a year later a fitting came loose and while my boss hand one hand on either conduits and pushing them together one of the 480 volt wires shorted out. He came close to be electrocuted. We investigated why the breaker did not clear this on the recently purchased used machine. Somebody had tied this circuit to a 400 amp circuit breaker . We now run copper ground wires in every conduit. Better safe then dead. I still do not use or trust the cheap die cast EMT fittings especially the junk made in India or China.
There again, this near tragedy was the result of a shoddy electrician who tied what sounds like what seems to be at most a 60 amp circuit to a 400 amp Overcurrent Protection Device.

It's likely, seeing as how this was a 3/4" conduit, and, the circuit was tied to a 400 amp breaker, that a #10 wire type EGC in this scenario probably wouldn't have helped to clear the fault either.


JAP>
 

Strathead

Senior Member
There's no way to prove that by simply installing a wire type EGC it will magically create a path of lesser resistance.



JAP>
I suspected that was what you meant. That is funny. Read it again. I was using it as an idiom. As a second year Apprentice instructor I avoid ever using the term "path of least resistance" in regards to electrical work, because it is not literally correct. All available paths inversely proportional to their resistances is electrically correct.
 

Strathead

Senior Member
There again, this near tragedy was the result of a shoddy electrician who tied what sounds like what seems to be at most a 60 amp circuit to a 400 amp Overcurrent Protection Device.

It's likely, seeing as how this was a 3/4" conduit, and, the circuit was tied to a 400 amp breaker, that a #10 wire type EGC in this scenario probably wouldn't have helped to clear the fault either.


JAP>
We get it. You don't want to install ground wires in conduits. Don't. Code allows you as a minimum installation, not to install a ground wire in a conduit. It also allows you to use romex and plastic boxes in a commercial strip mall build out too. Go for it, you can have that work and I will bid on other jobs, and proudly put our company's label on the panels.
 

jap

Senior Member
We get it. You don't want to install ground wires in conduits. Don't. Code allows you as a minimum installation, not to install a ground wire in a conduit. It also allows you to use romex and plastic boxes in a commercial strip mall build out too. Go for it, you can have that work and I will bid on other jobs, and proudly put our company's label on the panels.
No you don't get it.

As I said before, We always install a wire type EGC and always have, and, I'll put my company's label up against yours any day.

In the end the return path is dependent on the path itself and how well that path was created to begin with.

JAP>
 

jap

Senior Member
Code allows you as a minimum installation, not to install a ground wire in a conduit. It also allows you to use romex and plastic boxes in a commercial strip mall build out too. Go for it, you can have that work and I will bid on other jobs, and proudly put our company's label on the panels.
Yes, code does allow you to do all of these things.

And,

Just because you don't agree with this type of install, it doesn't mean that there aren't others who can't install a perfectly professional job using those options.

JAP>
 

kwired

Electron manager
I agree, but in the scope of long term work in a jurisdiction it would end up being the path of least resistance to just put a ground in. I have rolled over to an inspector on things a lot more heinous than this just because it was going to be the best bet in the long run.
But you indicated if you were the inspector you wouldn't need to get to that up high box if I pulled an EGC in the conduit, but if I used the conduit for EGC you would want to have access to that up high box (or something to that effect). If I pulled a EGC how you know I even connected it in the up high box if you don't go up there and verify??
 

Strathead

Senior Member
Yes, code does allow you to do all of these things.

And,

Just because you don't agree with this type of install, it doesn't mean that there aren't others who can't install a perfectly professional job using those options.

JAP>
Which is said earlier. It isn't an issue of "agreeing". I know the code. I am also very aware of article 90. Code minimum is a valid acceptable standard to perform installations. Luckily we are not forced to install to minimums. I am arrogant enough to, on some level believe my ways are the best, while intelligent and self-aware enough to realize that everyone other good electrician has a different set of standards and many, probably most, including yours are actually every bit as "best" as I think mine are.

(The above is intended to be taken lightly, with a certain amount of humor, a certain amount of humility and a certain amount of self truth. Please take it that way.) After all don't you believe your ways are the best ways?:p Anyone who says no, I ask, 'Then why don't you do it the best way?"
 

Strathead

Senior Member
But you indicated if you were the inspector you wouldn't need to get to that up high box if I pulled an EGC in the conduit, but if I used the conduit for EGC you would want to have access to that up high box (or something to that effect). If I pulled a EGC how you know I even connected it in the up high box if you don't go up there and verify??
Nope, I didn't state, "need" from any code perspective. I was trying to convey that I would make it more difficult for you, if you chose not to install a green ground wire in your conduits. I also stated the reason. My belief that even the best of us overlook things on occasion. A fault return path is important enough to me that I would be OK with being an a$$ about that. Regarding the high up box, I am not that concerned about a single, not readily accessible box being well bonded. Again, I am not an inspector, I never will be an inspector, everyone was stating how they don't run grounds in conduits, I was presenting the other side. And for the record on a personal level, most of the electricians and contractors that I know prefer to install a ground wire in their conduits. Sort of like how we used to just drive two ground rods instead of testing to prove they had less than 25 ohms resistance.
 

david

Senior Member
Less then a year later a fitting came loose and while my boss hand one hand on either conduits and pushing them together one of the 480 volt wires shorted out. He came close to be electrocuted.
Just curious where was the short the panel side or the side the equipment ground was compromised on. I am guessing this coupling was at a 90 deg. bend, if an attempt was made to push the conduit into a coupling.

You and your boss most likely had a conversation about pinching the wire while doing it on a live circuit
 

jap

Senior Member
If I pulled a EGC how you know I even connected it in the up high box if you don't go up there and verify??

Because K-wired, he said if he ever became an inspector he would make it more economical for us all to install a wire type EGC.

Which I guess means he would pay us for the labor and material required to install one, not sure.

If I was going to pay for the wire and labor to install a wire type EGC,that I couldn't enforce to be installed, you better bet I'd be up there crawling around making sure it was installed properly also.

JAP>
 

jap

Senior Member
Just curious where was the short the panel side or the side the equipment ground was compromised on. I am guessing this coupling was at a 90 deg. bend, if an attempt was made to push the conduit into a coupling.

You and your boss most likely had a conversation about pinching the wire while doing it on a live circuit
I agree.

If the thought of possibly shorting out the wiring, while trying to push the pipe back together full of energized circuit didn't come to mind, It should have.

JAP>
 

cowboyjwc

Moderator
Staff member
I think that the reason you see an EGC in EMT is that there are probably inspectors that require it.

We were told at a seminar that article 250 is probably the most misunderstood and misinterpreted article in the NEC

I can't tell you how many EC's put in two ground rods for a panel and the run another ground all the way to the front of the house, because they were told that's what's required. Yeah if you're using it for grounding, but if you're only bonding the cold water or the house has PEX, then you don't need it. I guess the city of Los Angeles, which is right next to us, requires it for some reason.

I've had very highly respected people in the trade tell me that grounding is highly over rated.
 

Strathead

Senior Member
Because K-wired, he said if he ever became an inspector he would make it more economical for us all to install a wire type EGC.

Which I guess means he would pay us for the labor and material required to install one, not sure.

If I was going to pay for the wire and labor to install a wire type EGC,that I couldn't enforce to be installed, you better bet I'd be up there crawling around making sure it was installed properly also.

JAP>
No, the code requires all joints to be made up tight. If they are not made up tight and there is also you ground wire in the conduit then there is a much higher potential for not having a ground fault path of sufficient ampacity. I assume you agree with that statement. If you knew that your inspector was going to spot check several connectors and couplings, every time you installed a conduit run without a ground, thereby making you inspections longer, and IF he found one that wasn't tight especially on more than one occasion he would be within his right to require an independent verification that all couplings and connectors were made up tight at your cost. Most of us would just install grounds in the conduits. As I implied more than once, I have done many things because I knew that the inspector preferred it a certain way and it just made my life easier all the way around. Even the best of inspectors is going to make life more difficult at every turn when they don't like an installation, but can't do anything about it. In my area I guarantee that the local inspectors will look more closely at everything we do, if we were not pulling a green wire in our conduits. Perhaps others here are perfect, but I will admit that if an inspector looks closely enough he can probably find a reason to fail my guys on every significant inspection. Kind of like offensive holding in a football game.
 

david

Senior Member
I think that the reason you see an EGC in EMT is that there are probably inspectors that require it.

We were told at a seminar that article 250 is probably the most misunderstood and misinterpreted article in the NEC

I can't tell you how many EC's put in two ground rods for a panel and the run another ground all the way to the front of the house, because they were told that's what's required. Yeah if you're using it for grounding, but if you're only bonding the cold water or the house has PEX, then you don't need it. I guess the city of Los Angeles, which is right next to us, requires it for some reason.

I've had very highly respected people in the trade tell me that grounding is highly over rated.
its been my experience the electrical engineer specifies a wire type equipment ground in there specifications

here most of our water supply lines are metal from the curb to the meters in our buildings basements. So it is necessary to make the bond to the first five ft. even when it means running the length to the opposite side of a basement
 

david

Senior Member
No, the code requires all joints to be made up tight. If they are not made up tight and there is also you ground wire in the conduit then there is a much higher potential for not having a ground fault path of sufficient ampacity. I assume you agree with that statement. If you knew that your inspector was going to spot check several connectors and couplings, every time you installed a conduit run without a ground, thereby making you inspections longer, and IF he found one that wasn't tight especially on more than one occasion he would be within his right to require an independent verification that all couplings and connectors were made up tight at your cost. Most of us would just install grounds in the conduits. As I implied more than once, I have done many things because I knew that the inspector preferred it a certain way and it just made my life easier all the way around. Even the best of inspectors is going to make life more difficult at every turn when they don't like an installation, but can't do anything about it. In my area I guarantee that the local inspectors will look more closely at everything we do, if we were not pulling a green wire in our conduits. Perhaps others here are perfect, but I will admit that if an inspector looks closely enough he can probably find a reason to fail my guys on every significant inspection. Kind of like offensive holding in a football game.
The majority of our conduit runs, up high, are fastened to metal bar joist in this area, so in that sense you are building an equipment grounding system that includes paths created by fasting to the metal bar joist

Since I have experience on the electrical installation side , i can sometimes spot a set screw that is longer than others. But i can not determine if a coupling is lose unless it is lose at both sides of a coupling even if i where to twist the coupling
 

jap

Senior Member
No, the code requires all joints to be made up tight. If they are not made up tight and there is also you ground wire in the conduit then there is a much higher potential for not having a ground fault path of sufficient ampacity. I assume you agree with that statement. If you knew that your inspector was going to spot check several connectors and couplings, every time you installed a conduit run without a ground, thereby making you inspections longer, and IF he found one that wasn't tight especially on more than one occasion he would be within his right to require an independent verification that all couplings and connectors were made up tight at your cost. Most of us would just install grounds in the conduits. As I implied more than once, I have done many things because I knew that the inspector preferred it a certain way and it just made my life easier all the way around. Even the best of inspectors is going to make life more difficult at every turn when they don't like an installation, but can't do anything about it. In my area I guarantee that the local inspectors will look more closely at everything we do, if we were not pulling a green wire in our conduits. Perhaps others here are perfect, but I will admit that if an inspector looks closely enough he can probably find a reason to fail my guys on every significant inspection. Kind of like offensive holding in a football game.
As I said earlier. A wire type EGC is no better than a conduit type EGC if it's not terminated properly.

There's just as much chance that the EC may have happened to miss bonding a wire type EGC to a box as there is in his missing tightening a connector on a piece of EMT.

If you install a wire type EGC inside of a raceway that is already accepted as and EGC, and the inspector takes issue with any of it,then, in my mind, your more than likely going to have twice as many connections to check.

In most cases, those who fear what an inspector might say lack confidence in what they know is right in their own minds.

As you told me earlier,,, if you want to install that wire type EGC even if it's not required,,, "Go Ahead", just don't be teaching those young minds that it's required.

JAP>



JAP>
 

electrofelon

Senior Member
No, the code requires all joints to be made up tight. If they are not made up tight and there is also you ground wire in the conduit then there is a much higher potential for not having a ground fault path of sufficient ampacity. I assume you agree with that statement. If you knew that your inspector was going to spot check several connectors and couplings, every time you installed a conduit run without a ground, thereby making you inspections longer, and IF he found one that wasn't tight especially on more than one occasion he would be within his right to require an independent verification that all couplings and connectors were made up tight at your cost. Most of us would just install grounds in the conduits. As I implied more than once, I have done many things because I knew that the inspector preferred it a certain way and it just made my life easier all the way around. Even the best of inspectors is going to make life more difficult at every turn when they don't like an installation, but can't do anything about it. In my area I guarantee that the local inspectors will look more closely at everything we do, if we were not pulling a green wire in our conduits. Perhaps others here are perfect, but I will admit that if an inspector looks closely enough he can probably find a reason to fail my guys on every significant inspection. Kind of like offensive holding in a football game.
IMO it is not any less important to have tight fittings in a conduit run where a wire EGC is used. Even with a wire EGC, the conduit will still be the only fault path for a majority of the circuit length.

I've had very highly respected people in the trade tell me that grounding is highly over rated.
Not sure if you mean earthing or bonding, but even bonding has become this panacea of importance and safety and IMO there are other things that are just as if not more important. Never hear anyone use a redundant GFCI or OCPD.....
 

jap

Senior Member
By threat of making the inspection "more difficult" if not there.
If you have an inspector threating to make an inspection "more difficult" for things that are perfectly acceptable by the NEC, you have bigger fish to fry.

JAP>
 

ActionDave

Moderator
Staff member
....I've had very highly respected people in the trade tell me that grounding is highly over rated.
....Not sure if you mean earthing or bonding, but even bonding has become this panacea of importance and safety and IMO there are other things that are just as if not more important. Never hear anyone use a redundant GFCI or OCPD.....
Could be both, the Dirt Worshipers and The Cult of the Green Wire seem to be gaining more converts every year.
 

Strathead

Senior Member
If you have an inspector threating to make an inspection "more difficult" for things that are perfectly acceptable by the NEC, you have bigger fish to fry.

JAP>
I am sure he is talking about implied threat. You really live in a Utopia where your inspectors have no personal opinions, treat every contractor exactly the same, enforce every code exactly as written and don no favors or make things difficult for anyone?
 

jap

Senior Member
I am sure he is talking about implied threat. You really live in a Utopia where your inspectors have no personal opinions, treat every contractor exactly the same, enforce every code exactly as written and don no favors or make things difficult for anyone?
There you go assuming again.

What about his statement below seemed implied?

By threat of making the inspection "more difficult" if not there

Sure the inspectors in my area have their own opinions just like I do. We just hash it out.

I've earned their respect over the years, and, I respect them also.

However, I don't have to do unnecessary things, such as installing additional wire type EGC when I already have an EGC like your having to do for fear of them finding something wrong in your work.

JAP>
 

jap

Senior Member
If they find something I did wrong, I simply make it as it should be.

Isn't that what the 2nd look is all about anyway?

JAP>
 

MAC702

Senior Member
It case it was forgotten/missed, I was quoting a member in this thread on what he would do as an inspector.

Thought it should be noted in context, and he is NOT an inspector.
 

Strathead

Senior Member
There you go assuming again.

What about his statement below seemed implied?



JAP>
Just because an inspector overtly threatening to fail someone for following code is not in my wheelhouse of experience and would likely result in disciplinary action against the inspector. That's all.
 

jap

Senior Member
Just because an inspector overtly threatening to fail someone for following code is not in my wheelhouse of experience and would likely result in disciplinary action against the inspector. That's all.
You said this:

I was trying to convey that I would make it more difficult for you, if you chose not to install a green ground wire in your conduits

You do know do know the mystery inspector he was referring to was you, right?

This would get you some disciplinary action on your first day of the job if you came on my jobsite trying to enforce a non-existent rule.

JAP>
 

MAC702

Senior Member
It case it was forgotten/missed, I was quoting a member in this thread on what he would do as an inspector.

Thought it should be noted in context, and he is NOT an inspector.
I hate not being able to edit my posts.

I typo'd and it should say: "Though it should be noted in context."

It changed the meaning. Apologies.
 

jap

Senior Member
To my knowledge there is nothing in the code that states EMT has to be supplemented by a wire type EGC.


JAP>
 

jap

Senior Member
I hate not being able to edit my posts.

I typo'd and it should say: "Though it should be noted in context."

It changed the meaning. Apologies.
That's ok, the other day I wrote Eaton and it posted as Easton, when a baseball bat had nothing to do with the subject. :)


JAP>
 

Strathead

Senior Member
You said this:

I was trying to convey that I would make it more difficult for you, if you chose not to install a green ground wire in your conduits

You do know do know the mystery inspector he was referring to was you, right?

This would get you some disciplinary action on your first day of the job if you came on my jobsite trying to enforce a non-existent rule.

JAP>
Just for the record I am done.
 

difowler1

Senior Member
emt as ground

emt as ground

Seen many from the time period you mentioned with poorly supported raceway contributing to broken fittings resulting in loss of EGC, also seen loose set screws or compression nuts, but that is all workmanship issues more than anything IMO. Have seen poorly made up EGC's in cable wiring methods as well - open continuity is still open continuity.

I do a lot of grain storage bins and handling equipment. Generally all steel structures and equipment. I do run EGC's in flexible conduits or in any non metallic raceways (which is usually just underground raceways in these applications) but see running any wire EGC in most of said systems as pointless, the equipment/structures are very effective fault return path, and usually more effective than my raceways, so if a fitting didn't get tightened it doesn't really matter much from equipment grounding perspective.
thanks for the comments as usual.
 

cowboyjwc

Moderator
Staff member
Inspectors? or Engineers?

How can an inspector require a wire type EGC if one is not spec'd on a project?

JAP>
How? They simply say that they want an EGC installed, but you knew the answer to that before you asked, I'm sure.
 

kwired

Electron manager
article 517
smarty pants:)

There is no general rule requiring EMT to contain an EGC. There are specific conditions where it is required.

If you want to be picky 517 doesn't use the term supplement either, it just says something to the effect that the wiring method must be one that qualifies as an EGC plus you must also run an insulated EGC within that wiring method. It also only applies to branch circuits supplying patient care areas, and not necessarily everything in the health care facility.
 

Gary11734

Senior Member
I wonder what this thread would sound like under this scenario;

We never used EMT, or rigid conduit to clear a fault since Edison played with the first light bulb. We ALWAYS pulled a separate wire to clear a fault.
Now, someone is proposing in the current NEC we use the raceways to clear a fault to save resources.
You would NEVER get this in the codebook. And I mean, NEVER.

It's just the way humans think!
 

kwired

Electron manager
I wonder what this thread would sound like under this scenario;

We never used EMT, or rigid conduit to clear a fault since Edison played with the first light bulb. We ALWAYS pulled a separate wire to clear a fault.
Now, someone is proposing in the current NEC we use the raceways to clear a fault to save resources.
You would NEVER get this in the codebook. And I mean, NEVER.

It's just the way humans think!
One problem with that is we went for some time without worrying about fault clearing at all, then went to only certain instances needed equipment grounding, and finally 1955-1960 finally started to go with EGC's required for pretty much everything, and even that took some time to catch on in some places.
 

jap

Senior Member
I wonder what this thread would sound like under this scenario;

We never used EMT, or rigid conduit to clear a fault since Edison played with the first light bulb. We ALWAYS pulled a separate wire to clear a fault.
Now, someone is proposing in the current NEC we use the raceways to clear a fault to save resources.
You would NEVER get this in the codebook. And I mean, NEVER.

It's just the way humans think!
I'm not sure about that.

I'll use an example that came up earlier in this thread.

"We never used NM and plastic boxes for commercial installations. We always ran it in conduit or MC cable no matter what. Now someone is proposing in the current NEC that we can use NM and plastic boxes to save resources". How dare they!!! and yes, it did get in the code book, and humans do utilize the option.

It's just the way humans are, like it or not.

JAP>
 

Gary11734

Senior Member
I'm not sure about that.

I'll use an example that came up earlier in this thread.

"We never used NM and plastic boxes for commercial installations. We always ran it in conduit or MC cable no matter what. Now someone is proposing in the current NEC that we can use NM and plastic boxes to save resources". How dare they!!! and yes, it did get in the code book, and humans do utilize the option.

It's just the way humans are, like it or not.

JAP>

Plastic boxes/wire, and grounding are comparing apples and oranges...

Grounding is the Holy Grail of the NEC. No comparison to plastic boxes. Plastic boxes were utilize because it's cheaper. Nobody gave a hoot about saving resources when plastic came out. They wanted to save money. And, you can save money by not pulling in a ground wire in conduit. It doesn't matter...

As I said, NO WAY would this ever get into the code. NEVER! I guarantee the code will finally get rid of the conduit as an effective means to clear a fault... It's just a matter of time...
 

Gary11734

Senior Member
One problem with that is we went for some time without worrying about fault clearing at all, then went to only certain instances needed equipment grounding, and finally 1955-1960 finally started to go with EGC's required for pretty much everything, and even that took some time to catch on in some places.
What codebook year did we not worry or care about if we cleared a fault?
 

david

Senior Member
As I said, NO WAY would this ever get into the code. NEVER! I guarantee the code will finally get rid of the conduit as an effective means to clear a fault... It's just a matter of time...
Please explain how a single fault clearing path through a single wire equipment ground is more effective than multiple paralleled paths through bonded metal conduits
 

jap

Senior Member
NEVER! I guarantee the code will finally get rid of the conduit as an effective means to clear a fault... It's just a matter of time...

That'd be an awful tall order to fill seeing as how conduit has already been proven to be a better conductor than the wire type.

Jap>
 

jap

Senior Member
Plastic boxes/wire, and grounding are comparing apples and oranges...
It isn't when your talking about conserving resources.

Those who don't learn how to adapt to the ever changing cost saving options that are available in the electrical industry will eventually find themselves behind the 8 ball on most project business.

Not everyone has industrial or commercial clients that will turn a blind eye to the difference in price every time.

Jap>
 

MAC702

Senior Member
That'd be an awful tall order to fill seeing as how conduit has already been proven to be a better conductor than the wire type.
Agreed, but if it happens, it will be from the argument that conduit fittings might be installed improperly at many places more difficult to inspect. We've all seen conduit runs sagging years later with loose fittings.

Yes, we've all seen improperly terminated wire EGC's, too, but that will be ignored.
 

tortuga

Senior Member
Wow 10 pages on a EGC in EMT!
As your self appointed resident code historian I will add that;
1/2" EMT (properly installed to NEC minimum) has a rating of 40 Amps as an EGC, 3/4" EMT has a rating of 60 Amps, 1" EMT = 100 Amps.
The conduit sizes were part of the equipment grounding conductor sizes from at least 1930 - 1965, what is T250.122 today.

The photo is from the 1965 NEC.

Cheers
 

Attachments

jap

Senior Member
Better yet.

Let's do an expirement.

Let's consider we're all mostly above average and are able to run conduit with all the fittings tight from beginning to end. I realize that might be a challenge,but, I feel we can do it.

Let's run 100' of 1/2" EMT straight from a panel to a 120v receptacle outlet, let's say on 2x4's or some other non conductive surface.

Now, let's pull wire to that receptacle, but, we're only going to pull 2 insulated wires a hot and a neutral in the conduit.

To add to the fun, we're going to strip about 5' of insulation off of the hot conductor at about the 50' mark so it will be sure to contact the inside of the conduit when we pull it in.

We terminate the wiring on both ends and turn on the breaker. Dead short and the breaker trips because it used the conduit as a return path.

Now we pull in a green insulated EGC,terminate it at the panel and receptacle, and turn the breaker on again, and, once again dead short and the breaker trips.

What did installing the wire type EGC do to help clear the fault? Not a damn thing.

Now, let's separate the EMT from the metal box at the receptacle end and turn the breaker back on.

Again, dead short and the breaker trips. What did the wire type EGC do to help clear the fault that time?. Not a damn thing.

Now lets leave the EMT seperated from the receptacle box, and, we're going to go back and separate every joint in the conduit by an inch simulating a shotty install and turn the breaker back on.

Hey!!! the breaker held that time even though we have a section of EMT at about the 50' mark That's energized with 120 volts. Since the seperated pipe can't clear that fault, what will our wire type EGC do to help clear that danger? Not a damn thing.

You can pull a wire type EGC and bond to your hearts content, but, depending on where the fault occurs,and where the conduit return path may have failed makes all the difference in whether or not it's actually going to help.


Jap>
 

Gary11734

Senior Member
Better yet.

Let's do an expirement.

Let's consider we're all mostly above average and are able to run conduit with all the fittings tight from beginning to end. I realize that might be a challenge,but, I feel we can do it.

Let's run 100' of 1/2" EMT straight from a panel to a 120v receptacle outlet, let's say on 2x4's or some other non conductive surface.

Now, let's pull wire to that receptacle, but, we're only going to pull 2 insulated wires a hot and a neutral in the conduit.

To add to the fun, we're going to strip about 5' of insulation off of the hot conductor at about the 50' mark so it will be sure to contact the inside of the conduit when we pull it in.

We terminate the wiring on both ends and turn on the breaker. Dead short and the breaker trips because it used the conduit as a return path.

Now we pull in a green insulated EGC,terminate it at the panel and receptacle, and turn the breaker on again, and, once again dead short and the breaker trips.

What did installing the wire type EGC do to help clear the fault? Not a damn thing.

Now, let's separate the EMT from the metal box at the receptacle end and turn the breaker back on.

Again, dead short and the breaker trips. What did the wire type EGC do to help clear the fault that time?. Not a damn thing.

Now lets leave the EMT seperated from the receptacle box, and, we're going to go back and separate every joint in the conduit by an inch simulating a shotty install and turn the breaker back on.

Hey!!! the breaker held that time even though we have a section of EMT at about the 50' mark That's energized with 120 volts. Since the seperated pipe can't clear that fault, what will our wire type EGC do to help clear that danger? Not a damn thing.

You can pull a wire type EGC and bond to your hearts content, but, depending on where the fault occurs,and where the conduit return path may have failed makes all the difference in whether or not it's actually going to help.


Jap>
You need to read my first post on this.

The question was;

IF WE ALWAYS PULLED A GROUND WIRE IN since the first days of Edison and NEVER used the raceway system to clear a fault, then, could we now say today we want to eliminate the wire and use only the conduit? I say, NO. It would NEVER pass the code gurus in today's climate.

Now, we have back data of one hundred years that conduit can be an effective means to clear a fault. But, that doesn't matter. Today, more is better and they will eliminate the conduit system for the wire in due time...

And, we are basing the grounding means of conduit on a workmanlike manner, not some trunk slammer doing moonlighting. The conduit system is an efficient means to clear a fault but we will eliminate it in due time for that precious green wire. Now, of course, IMHO!
 

jap

Senior Member
The conduit system is an efficient means to clear a fault but we will eliminate it in due time for that precious green wire. Now, of course, IMHO!

Electricity itself will never let us eliminate the conduit system as an efficient means to clear a fault.

It's going to utilize it regardless of whether a code rule ever gets put in place to add an additional green wire to it.


JAP>
 
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