SER and PVC

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brichter said:
Is it code compliant to install aluminum SER in ridgid non-metallic conduit underground?
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See this thread for the recent argument on the matter.

In my opinion, SE cable installed inside a conduit is not underground. Underground is described by the UL as being synonymous with "Direct Burial", which would not describe the installation of this SER.

300.5 requires cables directly buried or cables installed in conduits that are directly buried to be rated for wet locations, as SER is. Therefore, SER can be legally installed in a raceway underground, IMO. :)
 
Past history, over the years I have gone on alot of service calls where the customer was complaining about dimming lights, in 5-6 of those cases I found the bare nuetral wire coming in on the aluminum se cable basicly non existant, this was caused by water leaking into the cable by either a bad weatherhead or leaking of the weathertight connector on the meter socket and settling into a low spot in the cable, now maybe the nuetral being a current carrying conducter the current flow helped the wire to corrode at a faster rate then a grounding conducter but I wouldn't feel comfortable submerging an ser cable into a water filled conduit with a bare aluminum wire, just a pin hole and then it's just a matter of time. As far as the legality I'll let others debate that but is it good practice? I don't think so.
 
georgestolz said:
In my opinion, SE cable installed inside a conduit is not underground.
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I would have to disagree with that. A conduit's interior is not a location, whether above or underground. Any conductor or cable installed underground, whether in a conduit or not, must be rated for wet locations.

Direct-burial is a separate listing, and is required for any cable or conduit underground and not in a conduit. There is a difference between underground and direct-burial as far as the NEC is concerned.
 
LarryFine said:
Direct-burial is a separate listing, and is required for any cable or conduit underground and not in a conduit. There is a difference between underground and direct-burial as far as the NEC is concerned.
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Than I would say you did not really read the other thread.

Info from UL disputes your view.
 
LarryFine said:
A conduit's interior is not a location, whether above or underground. Any conductor or cable installed underground, whether in a conduit or not, must be rated for wet locations..
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If the conduit is not a 'location' than we would need to install conductors in that conduit that are rated for underground use, not simply type 'W" conductors.

On the one hand your saying SER (which is rated for wet locations) can not be installed in a conduit underground.

On the other hand your saying that THWN which is only rated wet can be installed in a conduit underground.

You can not have it both ways. :)
 
Code aside.
SER (Aluminum) in conduit underground? (Never have) and won't do it.
Type THWN (copper) underground in conduit? Have done it (and will again).
steve
 
iwire said:
If the conduit is not a 'location' than we would need to install conductors in that conduit that are rated for underground use, not simply type 'W" conductors.
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No, I'm saying that the conduit eliminates the need for a direct-bury rating. I wasn't aware that an 'underground use' rating (as opposed to direct-bury or wet) even existed. A wet rating is required for underground use, whether in conduit or not.

On the one hand your saying SER (which is rated for wet locations) can not be installed in a conduit underground.
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No, I was responding to George's "In my opinion, SE cable installed inside a conduit is not underground." This is similar to the discussion about using NM in conduit outdoors. If the conduit is outdoors, so is the wiring inside.

On the other hand your saying that THWN which is only rated wet can be installed in a conduit underground.
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Agreed. The conduit protects the wire from being directly buried, but it's still a wet location.

You can not have it both ways. :)
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Waaaaaaaahh! :(
 
LarryFine said:
No, I was responding to George's "In my opinion, SE cable installed inside a conduit is not underground." This is similar to the discussion about using NM in conduit outdoors. If the conduit is outdoors, so is the wiring inside.
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The cable is not underground, but that doesn't remove it from the ire of 300.5:
(B) Listing. Cables and insulated conductors installed in enclosures or raceways in underground installations shall be listed for use in wet locations.
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IMO, the way this is worded you could call the inside of the pipe vegetable soup, and it wouldn't matter. It's a cable inside a raceway underground, so it must be listed for wet locations. It never outright calls the inside of the pipe underground, or even wet for that matter. ;)
 
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georgestolz said:
The cable is not underground . . .
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It is if it's inside a conduit that is underground. The original post asked:

brichter said:
Is it code compliant to install aluminum SER in ridgid non-metallic conduit underground?
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georgestolz said:
It's a cable inside a raceway underground, so it must be listed for wet locations.
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Absolutely.

It never outright calls the inside of the pipe underground, or even wet for that matter. ;)
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It doesn't have to; if it's underground, it's underground, and it's a wet location, conduit or no. Above ground outdoors and unprotected by cover is also a wet location, conduit or no.

We are agreeing, aren't we?
 
SER is listed as suitable for above ground installation. If it is installed in a raceway undergound it is not listed for that purpose. If it is installed in a raceway above grade, I see not problem with that, as long as it is in compliance with the applicable codes.
 
I'm thinking that this issue is one that should be referred to the NFPA to get an "official" statement. Lots of opinions have been expressed, but it seems rather obvious that there is no consensus, and that indicates that the NEC requirements aren't clear. The only way to resolve this is to go to the source. I'd suggest that any question directed to the NFPA include more than just SE in underground conduit since there have been posts indicating that other commonly used wire types may also be inappropriate in underground conduit.

Martin
 
I would think the UL might be a better source. The NFPA might just regurgitate the text of 300.5, and follow it up by a 110.3(B), which leaves us back where we were. ;)
 
georgestolz said:
I would think the UL might be a better source. The NFPA might just regurgitate the text of 300.5, and follow it up by a 110.3(B), which leaves us back where we were. ;)
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Could be. It seems like the writers of the NEC think their prose is perfectly clear and concise most of the time. There's a response from UL in the parallel thread on TW, etc., underground, but it doesn't address cables directly. On the other hand, it seems to be mostly NEC text that's at issue with cables, so I'm not sure anything UL says will truly answer the question.

Martin
 
georgestolz said:
I would think the UL might be a better source. The NFPA might just regurgitate the text of 300.5, and follow it up by a 110.3(B), which leaves us back where we were. ;)
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Hmmm. And I thought we had it all resolved in those other threads. :confused: :)
 
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