SER Cable In Underground Conduit

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George
You mention that UL says that Direct burial and Underground are Synonymous...

Here is the UL response:

"1. ''Underground" and "Direct Burial" are not necessarily the same. "Underground" can mean installed in, and protected by, conduit. Underground in conduit is a wet location and a wet rated wire is permitted there. Direct burial, besides wet location, also allows for the cable to be placed directly in the ground, with no conduit protecting it, and backfilled with dirt (including any rocks that may be present) - which means these cables must be able to withstand abuse more than they would if they were protected by a conduit."


I am wondering how you get Synonymous from this statement?
 
Pierre I am wondering what reason you feel that UL or the NEC would prohibit a wet location cable from being installed a wet location?
 
I am not denying that THWN or any other cable listed for wet location cannot be installed in the mentioned locations.

I am questioning how he derived that the statement from Mike's response from UL is considered synonymous.


I do have questions about cables listed for wet locations, above grade - being installed underground in a raceway. It would seem to me that SER is listed for wet locations- outdoors (standard practive above grade). But is not listed for underground installations, of which a raceway installed underground is an Undgerground location.
 
Pierre C Belarge said:
It would seem to me that SER is listed for wet locations- outdoors (standard practive above grade). But is not listed for underground installations, of which a raceway installed underground is an Undgerground location.
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What does 300.5(B) require of Cables installed underground?

Can you point to a section in the NEC or UL that requires cables or conductors installed in raceways underground be specifically listed for 'underground'?

IMO the real issue is this, take it for what it's worth.

When they said 'for above ground' what they really had in mind was 'not for direct burial' .
 
why does art 338.10 (B) (4) (b) only refer you to aboveground installations for SE cabel used as a feeder or branch circuit?

iwire

are you saying that SER cable in an underground conduit is aboveground? I would not want to be a contractor in court trying to explain this type of installation when the cable fails and somebody got hurt.
 
mpd said:
are you saying that SER cable in an underground conduit is aboveground?
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Did I say that?

What I am saying is it is not direct buried and 300.5(B) only requires a cable installed in a conduit underground to be listed for wet locations. :cool:
 
iwire

if SE cable is not aboveground it is a violation, to say aboveground means not for direct burial makes no sense, aboveground is just that above the ground,

if you were an inspector would you pass an aluminum SER feeder underground in conduit to a detached garage?
 
mpd said:
if you were an inspector would you pass an aluminum SER feeder underground in conduit to a detached garage?
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Would the NEC allow me to run the same circuit in aluminum XHHW with a bare ground?
 
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iwire

that was not the question I asked you, if you were an inspector would you approve an aluminum SER feeder (3 insulated & 1 bare equipment ground)
underground in conduit to a detached garage?
 
mpd said:
iwire

that was not the question I asked you, if you were an inspector would you approve an aluminum SER feeder (3 insulated & 1 bare equipment ground)
underground in conduit to a detached garage?
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Kind of tough to answer as there is darn little info.

That said I would not fail it based only on SER being used in the raceway.

There may well be other reasons for a red tag.

Now how about you?

Would you fail the feeder you described if I used XHHW AL and a bare grounding conductor?

Based on what code section?
 
As per the instructions for SE types of cables and USE types of cables, if I saw an installation of SER (a type of SE cable) installed in a conduit installed underground I would definitely ask the installer for corrective measures.

If I saw XHHW installed in a conduit that is installed underground, I would not violate it as it is as per the NEC and UL properly installed.

If someone has issues with this, they should contact UL and the cable manufacturers to see if they could change the UL requirements. I would certainly accept a letter from UL and the manufacturer if they themselves were okay with an underground installation of SER. It takes the responsibility out of my hands...I love when the responsibility is not mine :wink: .
 
iwire

I would fail it and already have many times, I agree with pierre's post, I have had several contractors I have failed tell me they will be getting the info from the manufacture for SER underground in conduit, end result they were all replaced with a code compliant feeder, so for me it is not a tough answer, SER underground will fail everytime.
 
From U.L. online certifications directory

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.

SE cable has not been evaluated for use underground ,it is not listed for underground installations ,.. in raceways or in the softest white sand there is on earth .

What does 110.3 (b) mean it has the word "shall" in it ,.. and shall indicates a mandatory requirement,.. doesn't it:confused:

Bob , now you are saying they meant not direct burial when the stated aboveground installation?? I don't know ,..I think thats a bit of a reach

"When they said 'for above ground' what they really had in mind was 'not for direct burial' "
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I think alot of times people just look at the comentary like in Mike's publications and others...but as the NEC Code Panel stated....the NEC does not prevent the application of this.

I think in the applications that Bob are doing is shorter runs...could not imagine trying to pull SER in 50' of COMPLETED PVC with multiple 90's and so on....just nothing I am interested in doing personally....;)

The other issues simply could be space in the conduit, completed conduit issues and some other factors but I think the NEC does not in general rule out the application......

Art 338.2 States:

Type SE. Service-entrance cable having a flame-retardant,
moisture-resistant covering.
Type USE. Service-entrance cable, identified for underground
use, having a moisture-resistant covering, but not
required to have a flame-retardant covering.

So are we saying the fact USE says "identified for undergound use" and the lack of the verbage " Identified for aboveground use" in SE means it can't be in the conduit?

Here is what it says about SE as a branch circuit or feeder:

(B) Branch Circuits or Feeders.
(1) Grounded Conductor Insulated. Type SE service entrance
cables shall be permitted in wiring systems where
all of the circuit conductors of the cable are of the rubbercovered
or thermoplastic type.
(2) Grounded Conductor Not Insulated. Type SE
service-entrance cable shall be permitted for use where the
insulated conductors are used for circuit wiring and the
uninsulated conductor is used only for equipment grounding
purposes.
Exception: Uninsulated conductors shall be permitted as
a grounded conductor in accordance with 250.140, 250.32,
and 225.30 through 225.40.

While I again have reasons why I dont like the practice in the original posters example....50' worth......as the NEC Code Panel has stated the NEC believes it is acceptable.....does it not?

But does the UL trump this.........ahhhh.......might answer the question

Sorry.....I was presenting the debate and forgot to put the UL response.....directly from the 2005 UL Wire and Cable Guide

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.
Types USE and USE-2 — Indicates cable for underground installation including direct burial in the earth. Cable in
sizes 4/0 AWG and smaller and having all conductors insulated is suitable for all of the underground uses for which
Type UF cable is permitted by the NEC. Types USE and USE-2 are not suitable for use in premises or aboveground
except to terminate at the service equipment or metering equipment. Both the insulation and the outer covering,
when used, on single and multiconductor Types USE and USE-2, are suitable for use where exposed to sun.
 
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iwire

you said there may be other reasons for a red tag, what would they be? you still have not said if you would pass or fail this installation, I am kind of suprised because you do not seem to have a problem with this installation
 
is this subject finally put to rest, that you cannot use SE cable underground in conduit?
 
mpd said:
is this subject finally put to rest, that you cannot use SE cable underground in conduit?
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MPD--I am curious as to why you think there would be a problem with SE cable in conduit underground. If it is above ground in conduit you believe that is legal, I presume??? Above ground it still can have moisture in the conduit and in fact if it is a horizontal run, it is possible the cable would be sitting in water.

I understand your statements completely, however, I am asking you to step back and look at the situation without all the other info you have presented. Is there really anything in there that would make you feel this is unsafe? It is rated for wet location which means water won't hurt it. It is inside PVC-- It is protected.... What else is at issue here?

I have seen NM cable buried underground for 15 years running without issue. I have seen romex in pipe underground and outside on the side of a house for years on end. I do not condone the installation above and I am not trying to make light of it. I would never allow it or overlook it.

I personally don't like the installation that the OP has presented, however I can't imagine turning it down. To say the least the issue is very vague and not well presented in the code. Maybe someday that wording can be changed to be more precise.

Sometimes I think we go overboard trying to interpret ever intent of the code and play mind games with the wording in the code. "What does it really mean"? Sometimes it is not that important. Of, course, if you see it as an important issue then you have to do what you think is right.
 
mpd said:
iwire

you said there may be other reasons for a red tag, what would they be?
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Wrong overcurrent protection, subject to physical damage....you know.....all the other stuff.


you still have not said if you would pass or fail this installation,
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I have said, I guess you did not see it.

iwire said:
That said I would not fail it based only on SER being used in the raceway.
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mpd said:
is this subject finally put to rest, that you cannot use SE cable underground in conduit?
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Again that is simply your interpretation, it is no more or less valid then mine.

Just as you have shown links that support your position Dennis and George have posted links that support my position.

People can make their own minds up.
 
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