As an inspector, have you ever had a person want to install SER cable in conduit - underground? I wrote this up and the contractor insisted that first of all, he has never been written up on that before and secondly that the conductors were Listed XHHW so what's the problem?
So he offered to remove the jacket. Now we have a bare aluminum EGC in conduit in the ground.
Comments are invited.
George,
I’m not an inspector, but I can understand your frustration. I swear to god we must have covered this in every code cycle seminar I’ve been to for at least the last ten years. I have seen guys do this before, but not for many years. I guess the word still hasn’t gotten out to everyone.
Here is what the 2007 UL White book has to say:
Type SE— Indicates cable for aboveground installation. Both the individual insulated conductors and the outer
jacket or finish of Type SE are suitable for use where exposed to sun. Type SE cable contains Type RHW,
RHW-2, XHHW, XHHW-2, THWN or THWN-2 conductors.
338.12 Uses not permitted
(A)SE Cable
(2) Underground with or without a raceway
Which brings us back to stripping the cable off ....
Assuming the conductors are individually marked as to the insulation type, there's no violation. Nor is there any requirement that the ground wire be insulated.
However, it's likely that the individual wires are not marked - just the outer jacket. Remove the jacket, remove the listing.
Then there is the matter of aluminum in contact with the earth. Not allowed by code ... but is 'in the pipe' the same as 'in contact with earth?'
Excellent subject resurrection. I've butted heads with inspectors in my younger days about this, but now that I've matured a bit, I see where I was wrong. My last argument with an inspector yielded the most logical answer. I couldn't seem to understand the harm in running 6/3 Romex in a conduit for a short distance to a detached garage.
His answer was fairly simple and it certainly shut me up on this subject forever. A conduit in the ground is never dry and Romex is not approved for wet locations. People really do go around with the misconception that glued PVC is water-tight. Nothing could be farther from the truth.
I can see the both sides of the argument. SE is not for sub subsurface use, xhhw is. What a paradox.
Hmmmm,
Just to be sure, I went and stripped off about 3-feet of jacket on some aluminum SE and SER cables I have in stock and I couldn’t find any markings on the individual conductors, not even a voltage rating.
It seems that stripping the jacket off SE cable and using the unmarked conductors in that manner would be on par with stripping the sheath off NM-B cable and using the unmarked conductors for wiring up a #2 fuel oil pump, because we are sure they are gas and oil resistant THHN insulation.
If you set the way back machine to about a year ago you will see a thread I started about this. The #2 copper SER we had was marked THWN conductors on the jacket, nothing on the conductor. (I still have about 20-30' left over)
I am not sure what we decided here but the inspector didn't even blink. We were OK and off we went.
Greg, I read the old posts. It sounds like something right out of a Three Stooges skit, with the golf cart and all the pushing and pulling.
I think maybe that inspector should hang up his spurs and go back to sawing roast beef at Arby’s. Around here, he would have gotten the “Paper Hat” award for letting that one slip by.
Sounds rather like the health dept people who will let you add bedrooms to a house on septic, but you can't have any closets in the bedrooms.
I am still not sure what the violation would have been. The cable was marked "THHN or THWN"
http://esteroriverheights.com/electrical/ser.jpg
Greg,
Here is basically what we are told when this comes up at code seminars in my area, and it seems to come up at every one.
Without the outer sheath or jacket, the UL label/mark is now missing and is no longer valid since you have intentionally field altered a listed cable assembly by removing the outer jacket more than is necessary for normal splicing and termination. Without the jacket, there is also no cable or conductor identification as required in 310.11[A] or 310.11[B], [1].
With the outer jacket intact it is the cable assembly SE/SER, designed for use in above ground installations. With the jacket stripped off more than necessary for splicing and termination, it is now scrap since without the jacket it also doesn’t meet NEC 310.11 requirements for individual conductors or cable assemblies.
I’m pretty sure the reason that the conductors aren’t marked individually, is so that it would be obvious that they were designed and listed to be used only as a cable assembly with an overall jacket or sheath. Just like NM-B [Romex].
Anyway, this explanation makes sense to me and has been enforced by inspectors in my area for many years.