Ground or neutral?

[homnspector]

This panel (sub panel) was fed by 2 insulated conductors and one bare conductor in metal conduit. I am pretty sure that the bare conductor is not allowed as a neutral as it is in contact with the metal conduit which I am assuming is the grounding conductor. So what is the recommendation? Install an insulated neutral conductor and leave the uninsulated as a grounding conductor?

Also, obviously the neutrals and grounds have to be seperated or isolated.

I think these can be separated by removing a jumper. Looks like there is a spare larger lug.

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[Brian G]

Assuming it's exactly what you think it is, I'd just tell my client to replace both. It wouldn't cost much more, and I really don't trust many equipment grounds via conduit (particularly EMT). Why not be sure?

Brian G.

Surer Is Better-Er [:-thumbu]

[homnspector]

Brian, I don't see how the bare copper can be a problem as a ground, its just that it is in use as a neutral as far as I can determine.

Lemme splain agin: There are 2 insulated conductors in the EMT, both are hot. There is 1 bare stranded copper in the EMT connected to the neutral bus. I guess the EMT is used as a ground IF you consider the stranded bare copper a neutral. So, my theory is to install 1 additional insulated conductor for a neutral and leave the exiting bare copper as a ground. Am I missing something?

[Brian G]

Ahhh. Gotta read a little slower. That should work as long as the bare cable isn't too big to fit in the lug on the equipment ground bar. Some add-on bars don't have very big lugs, and neutrals are typically way bigger than equipment grounds. Was this one set up to be easily converted for sub panel use, or will an equipment ground bar have to be added?

I don't think the NEC endorses clipping out strands under any circumstances.

Brian G.

Cables Ain't Coupons [:-alien]

[Kyle Kubs]

Looking at your picture, the strands of the bare copper look to be too thin & too many to be a standard stranded wire... Are you sure this is not a feeder cable assembly with the Neutral insulated inside of the sheath surrounding the two hot lines? Also, be sure to differentiate between EMT and Rigid conduit. EMT is not permited to serve as a ground, Rigid is, with the correct fittings at the panels of course. In any event adding an insulated neutral and leaving the bare copper that is in contact with the conduit... I'm not sure that would be ok. I would never do it that way so I actually don't know for sure but I'm pretty sure it would not be permited.

Now all that said. Your best and least liable course of action is to call it what it is, Wrong and don't dictate a repair, let a Licensed Electrician determine the correct course action.

My $0.02

[homnspector]

Dang, nothing is ever simple.

"Wrong and don't dictate a repair"

Good point. But after reading your post, it sounds like it might actually be OK if it is a feeder cable assembly. (I am pretty sure if it was, the sheathing is stripped back farther than the conduit) AND if it is rigid conduit. How do you tell the difference between rigid conduit and EMT?

[chicago]

Just out of curiousity did you check the main panel end for comparison.?

They may have enough left over to clear the neutral back into the box.Assuming they stripped it to far into the conduit if I followed this right.

[Brian G]

Pictures! [:-magnify

First off, those bars can't be seperated. An equipment ground bar will have to be added, with all equipment grounds moved over. The enclosure must bonded there, and the bond removed from the neutral bar where it is now. The extra bar should be readily available.

Second, the single neutral in the other big lug needs to be moved to properly sized terminal.

Third, Kyle is probably right. Just try to arm your client with enough knowledge to protect himself if you won't be in the loop later. Some of the sparky's around here are bad to blow smoke up the client's butt if I'm not around to counter them (Aw hell, it's fine like it is. That home inspector's crazy).

Originally posted by homnspector

How do you tell the difference between rigid conduit and EMT?

Rigid is a heavy-wall conduit, like a 10 foot long pipe nipple. It can be threaded and typically has no markings on the outside. Fittings are usually malleable iron or steel.

EMT is a thin wall conduit, more like a stick of copper water line (electrical metallic tubing). You can't thread it, and it normally has inch markings on the outside (but not always). Fittings are usually steel or die cast.

Brian G.

I Prefer to Carry the EMT []

[chicago]

Around here Emt is used as ground all the time.

[Jim Katen]

Originally posted by chicago

Around here Emt is used as ground all the time.

Yes. EMT is fine as an equipment ground per NEC 250.118(4).

I suspect that Kyle is right about the feeder being a cable assembly in conduit.

I agree with Brian's assessment in his last post.

- Jim Katen, Oregon

[StevenT]

Rigid conduit also is made from aluminum. There are also compression fittings.

In NYC, EMT (and BX) are used for grounding almost all the time. I can't count how many times I've seen EMT separated at the joints.

[chicago]

True...Which is why I have seen arguments for NMC.

Just can't get past the giant extention cord visual when I see them.

I like the fact you can replace the conductors with out tearing up walls though.(with EMT).