What is an acceptable EGC?

[hillbilly]

I will volunteer to run a separate ground conductor thru all runs of emt as soon as the poco's of this country run a separate ground conductor with all their service drops....... We could save some cows lives with that one...

steve

 

[LarryFine]

Just out of curiosity, how many of us do omit the wire EGC when using metallic conduit?

I do, unless it's specified and paid for.

 

[LarryFine]

Somewhere out there is an electrician that can screw up the installation of an incandescent light bulb.

I've seen that, too. Ocer-tighten a bulb, and the screw-shell pops off the rivet that connects it to the white-wire terminal.

 

[nyerinfl]

Sorry, I meant RMC.

Just out of curiosity, how many of us do omit the wire EGC when using metallic conduit?

Not me........

As often as possible, especially on feeders. Less material, less wires to pull/make up, win win.

 

[macmikeman]

Here is another thing about the ground wire in metal conduit (which by the way is still nice to have in there don't get me wrong about it.) In certaing voltage drop upsize the feeder situations you may have to use larger conduit because of the proportional upsize in equipment ground conductor required. Leaving out the equipment ground conductor entirely and you go with the conduit you start with for the feeder.

 

[George Stolz]

The only problem I see is that the EMT raceway's fault path could be compromised with a loose set screw or locknut or if a metallic box in the middle of the run was replaced with a non metallic box after the fact (a long shot, I know, but it could happen).

Actually, installing a nonmetallic box would generally also be a violation of 314.3.

 

[Karl H]

Using the EMT as the EGC is minimum code compliance,but IMO is
poor design. I don't think there are any "experienced" service guys
that hasn't seen hundreds of loose fittings,lock-nuts, or pipes pulled
from their fittings when the EMT was used as the EGC. It's all about
safety. My experience tells me to "Pull a Green with Everything."

Sure you could argue loose splices,bonding screws,etc. Then you still
have the EMT to carry the fault current. If you have loose splices and
separated pipe, well , then it looks like your gonna have a bad day if
you decided to work energized on this hack job of a pipe run.

 

[radiopet]

Actually, installing a nonmetallic box would generally also be a violation of 314.3.

Very true...but if "done after the fact" then the AHJ would not know it and create a a problem in the entire system to that point. I did want to make a comment however on a statement larry made and I dont remember which it was. 95% of the Electrical Engineers are going to spec an EGC even with metal conduit. When I am doing plan review, if they call for it then it better be there or it is rejected in the field.....I have had electricians in an effort to save a buck choose to not run it when the engineer called for it and we have no choice but to fail it.

They will argue that it is compliant to the NEC and I will agree and then I will say but the "Stamped" and "Sealed" drawings say otherwise and since the engineer called for it we are not at liberty to change it unless they wish to call the engineer and ask the question, raise the point and convince them to change it via a new submital of drawings for full review.

 

[gndrod]

non-conductive

non-conductive

Actually, installing a nonmetallic box would generally also be a violation of 314.3.

Hi George,

Absolutely in agreement. Maybe Ex. 2 is a little labor intensive but necessary.

 

[LarryFine]

I did want to make a comment however on a statement larry made and I dont remember which it was.

Jedi mind trick.

95% of the Electrical Engineers are going to spec an EGC even with metal conduit. When I am doing plan review, if they call for it then it better be there or it is rejected in the field.....I have had electricians in an effort to save a buck choose to not run it when the engineer called for it and we have no choice but to fail it.

I have no problem with that, as long as it was bid and paid for, as I mentioned.

 

[brian john]

Using the EMT as the EGC is minimum code compliance,but IMO is
poor design. I don't think there are any "experienced" service guys
that hasn't seen hundreds of loose fittings,lock-nuts, or pipes pulled
from their fittings when the EMT was used as the EGC. It's all about
safety. My experience tells me to "Pull a Green with Everything."

Sure you could argue loose splices,bonding screws,etc. Then you still
have the EMT to carry the fault current. If you have loose splices and
separated pipe, well , then it looks like your gonna have a bad day if
you decided to work energized on this hack job of a pipe run.

And IMO that is a poor excuse for adding a cost to a job. Poor workmanship can screw up anything, as previously stated.

Look at it this way there is another conductor and the electrician says grounded conductor, grounding conductor which is which, oh I'll land them both here with all the white wires. AND WE SEE THIS ALL THE TIME. One less conductor for a misapplication screw up.

 

[Barjack]

This discussion mirrors the discussion I've been having with my superior. We have left messages with our local AHJ with no response as yet. There may be a local ordinance. From the talk here, I believe I now understand that while not required except under certain conditions, a wire EGC in a qualifying metallic raceway could either be considered a superior practice, or a waste of material. For my own, I believe I would always include one unless I was forced to omit it. It just gives me a warm fuzzy feeling to have it.

 

[Karl H]

And IMO that is a poor excuse for adding a cost to a job. Poor workmanship can screw up anything, as previously stated.

Look at it this way there is another conductor and the electrician says grounded conductor, grounding conductor which is which, oh I'll land them both here with all the white wires. AND WE SEE THIS ALL THE TIME. One less conductor for a misapplication screw up.

It is an insignificant cost compared to the liability of someone
injured or killed on a system you installed. Using EMT as a EGC
just doesn't meet "MY" design criteria.

 

[glene77is]

NEC is minimum code requirements.
I always pull an EGC.

 

[glene77is]

But does that mean the redundant EGC is only required to be in the patient care area, or once the AC or EMT exits the area (into the suspended ceiling and back to the panel) can the redundant EGC be omitted?

I have wired patient care areas,
and ran the EGC alway back to the panel.
The conduit changed from RNC(pvc) to EMT,
and I took no chances.
Even bonded the metal JB along the way.

Patients connected, sometimes with needles in the arm,
are very sensitive to leakage currents, induced currents,
etc.

Many years back, I worked at a Unversity hospital,
developing instruments. We took no chances.
I monitored leakage current at 10 microAmps max.
taking readings directly from the instruments.

 

[glene77is]

could either be considered
a superior practice,
or a waste of material.

BarJack,
You have the right idea.

I understand when reminded that I don't have to twist the joints prior to attaching a wire-nut. I have read the manufactures specs on the web, and they don't require it for legitimate reasons. But, since they require enough twisting to produce two twisted turns below the wire-nut skirt, I am happy doing the twist with my Kleins, using that superior torque leverage. I never have to go back for a loose joint.

I don't understand when told that the EGC is not important. Adjust the billing slightly! The other option is to put up with GFCI protection everywhere. Remember, this is a patient care area.

*** When the water leaks,
I call Keven my plumber,
and he comes around tomorrow.

*** When the paint is the wrong color,
I call Hector my painter,
and he comes around tomorrow.

*** When the voltage bites,
I might be on my way to the morgue!

:smile:

 

[glene77is]

... Are the requirements of 517.13(A) and (B) such that an insulated EGC is required all the way back to the panel, through the EMT, ...

BarJack,
Did I read the NEC right? For Patient Care areas ...
Does 517.13(A) require "metal" conduit all the way from the receptical box to the circuit breaker box ???

If so,
then the specs on a previous job I did were at fault.

If EMT and RNC are both used,
then the idea of a Redundant ground is broken.
So, Then,
would we have to pull TWO EGC insulated conductors
to provide the redundant ground?

Looking forward to the comments...

 

[glene77is]

Actually, installing a nonmetallic box would generally also be a violation of 314.3.

You do allow for except (1) and (2), right?
'General' refers to some standard practice, right?

I 'general'ly follow your method in my work.
Good practice. I also pull an EGC everywhere.

:smile:

 

[George Stolz]

You do allow for except (1) and (2), right?

Obviously, there are exceptions to the rule, which is why I used the term "generally." I do not have an SOP for dealing with this code.

 

[radiopet]

Jedi mind trick.

I have no problem with that, as long as it was bid and paid for, as I mentioned.

The good news is if we see a conduit with only (3) wires and we think it is using the conduit as the EGC, we will ask the Engineer. And guess what, most of the time they say...opps, we intended for an EGC to be present. I can see where this makes it hard for the EC who is bidding off a set that has not been finally approved yet so all bids should be conditional. To be honest I wish all owners would submit plans prior to accepting bids so that when they submit them to contractors like yourself, eveyone is on the same playing field.

But it does not always work that way....I am aware of that fact...lol