ECN Forum
Posted By: shortcircuit type SER cable - 11/24/04 11:14 PM
In a recent post by "royta" 11-18-04 he mentioned type 6-3 SER in a 3/4 inch pipe to a building, which I think is a underground installation.I looked at a job today with a 2inch pvc underground to a barn with a 2/3 SER aluminum cable stuffed in it to feed a panel.

I thought that Type SE or SER was only for above ground use...even if in a conduit...right?

shortcircuit
Posted By: hbiss Re: type SER cable - 11/25/04 02:12 AM
Right.

-Hal
Posted By: Redsy Re: type SER cable - 11/25/04 03:17 AM
Look at this. It might help:
https://www.electrical-contractor.net/ubb/Forum2/HTML/000254.html
Posted By: tdhorne Re: type SER cable - 11/26/04 04:17 PM
Quote
I thought that Type SE or SER was only for above ground use...even if in a conduit...right?
Sorry that is wrong. Type USE is limited to underground and outdoor use because it is not fire retardant treated. Type SE and Se-R is permissible in any application were Type USE is allowed as well as for inside of buildings because it is fire retardent treated. Type SE-R has the bare conductor as an individual conductor rather than as an overwrap of the other conductors. The R=round were a "C" would mean Concentric. Type SE-R is permitted in underground conduit. The conduit fill calculation is done by taking the cross sectional area of the cable and assuring that it is less than fifty three percent of the cross sectional area of the conduit. In other words for conduit fill purposes the entire cable is treated as a single conductor.
--
Tom H

[This message has been edited by tdhorne (edited 11-26-2004).]
Posted By: iwire Re: type SER cable - 11/26/04 04:32 PM
Tom do you have any references for using SE underground?

2003 UL White Book
SERVICE CABLE (TXKT)
SERVICE ENTRANCE CABLE (TYLZ)
GENERAL
Quote
The cable is designated as follows:
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.

I can not find anything that says Type SE is allowed underground.

Bob
Posted By: iwire Re: type SER cable - 11/26/04 04:39 PM
I should have included the USE info too.

2003 UL White Book
SERVICE CABLE (TXKT)
SERVICE ENTRANCE CABLE (TYLZ)
GENERAL

Quote
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.
Posted By: tdhorne Re: type SER cable - 11/26/04 04:55 PM
338.2 Definitions.
Service-Entrance Cable. A single conductor or multiconductor assembly provided with or without an overall covering, primarily used for services, and of the following types:
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.

Notice that the difference between the two cable types is that type USE is not required to have a flame retardant outer jacket. That is what limits it to outdoors, if sunlight resistant, and underground. Type SE has all the characteristics of Type USE and it also has a flame-retardant covering. Type SE can be used anywhere that type USE can be used as well as being used as feeder and branch circuits in any application were type NM can be used. The U in Type USE is to limit it's use to underground rather than to limit the use of type SE to above ground. We have batted around the idea that conduit is a wet location when installed outdoors. I don't think that any of us would argue that a conduit that is above ground outdoors is uniquely different than the same conduit underground.

Let me point out that Type SE Style R is the only type of SE commercially available in most ares that has four conductors. Has anyone here seen four conductor type USE cable. How do you think that three phase service gets done were the cable has to extend indoors to reach the service equipment cabinet? Do all of you build raceway to enclose individual single conductor type USE cables?
--
Tom H

[This message has been edited by tdhorne (edited 11-26-2004).]
Posted By: iwire Re: type SER cable - 11/26/04 05:02 PM
Tom, characteristics not withstanding SE is not UL listed for underground use.

Unless you have some info that says otherwise.

Bob
Posted By: iwire Re: type SER cable - 11/26/04 05:04 PM
Quote
Let me point out that Type SE Style R is the only type of SE commercially available in most ares that has four conductors. Has anyone here seen four conductor type USE cable. How do you think that three phase service gets done were the cable has to extend indoors to reach the service equipment cabinet? Do all of you build raceway to enclose individual single conductor type USE cables?

Run RHW in a raceway?
Posted By: tdhorne Re: type SER cable - 11/26/04 06:16 PM
The maxim of the law is that silence is consent. That means that anything that the law does not specifically forbid it allows.
--
Tom H
Posted By: tdhorne Re: type SER cable - 11/26/04 08:36 PM
Quote
Tom, characteristics not withstanding SE is not UL listed for underground use.

Unless you have some info that says otherwise.

Bob
Bob
Is THWN listed for use underground? If not then why do we use it in underground conduit. I believe that any conductor or cable that is suitable for use in wet locations is suitable for use in conduit outdoors. I fail to see how it makes any difference that the conduit may be partially, substantially or entirely underground. If we were talking about direct burial I could see a possibility of there being a problem.
--
Tom H
Posted By: iwire Re: type SER cable - 11/26/04 08:42 PM
I will post the UL info in it's context and you can decide if UL is silent on this.

I will also post some handbook opinion and some NEC definitions.

2003 UL White White Book.
Quote
SERVICE CABLE (TXKT)
SERVICE ENTRANCE CABLE (TYLZ)
GENERAL

This category covers service entrance cable designated Type SE and Type USE for use in accordance with Article 338 of NFPA 70, ‘‘National Electrical Code’’ (NEC).

Service entrance cable, rated 600 V, is Listed in sizes 14 AWG and larger for copper, and 12 AWG and larger for aluminum or copper-clad aluminum. Type SE cable contains Type RHW, RHW-2, XHHW, XHHW-2, THWN or THWN-2 conductors. Type USE cable contains conductors with insulation equivalent to RHW or XHHW. Type USE-2 contains insulation equivalent to RHW-2 or XHHW-2 and is rated 90°C wet or dry.

The cable is designated as follows:

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.

Now honestly, don't you think it would say "Type SE — Indicates cable for aboveground or underground installation." if that was what the listing allowed?

Here is some info from the 2002 NEC handbook following 338.1

Quote
Type SE, 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 USE or USE-2, cable for underground installation, including burial directly 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 Code. Types USE and USE-2 are not suitable for use in premises or above ground 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.


Please note no mention of using SE underground.

Here is 2002 NEC 338.2
Quote
338.2 Definitions.
Service-Entrance Cable. A single conductor or multiconductor assembly provided with or without an overall covering, primarily used for services, and of the following types:

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.

Notice that the definition for type SE is missing the words "identified for underground use" that are present in the definition for type USE.

I hope someone else will jump in here, I have a lot of respect for Tom's opinions he is a knowledgeable member here and perhaps there is something I am missing.

Bob
Posted By: iwire Re: type SER cable - 11/26/04 08:52 PM
Tom I was typing while you where posting.

Quote
Bob
Is THWN listed for use underground?

That is an interesting point.

Can I ask a couple of questions

Why use a cable if the raceway runs form point to point?

Is it allowed to run SE cable in a complete raceway? Not just a short section for physical protection.

The 2002 NEC did not allow NM cable in a complete raceway, there is a change in 2005 to allow this.


Bob
Posted By: earlydean Re: type SER cable - 11/26/04 09:22 PM
A wet location is defined in Article 100 as installations underground.....
That tells me that if I run conduit underground, I need an insulation with a W in it's designation.
The letter U in a conductor designation stands for underground.
I buy SEU cable for my services, not SE cable. I therefore can run this cable underground in conduit. (assuming that cable desigantions are the same as conductor designations) Also, the conductors have a W in their designation. I cannot direct bury it, as it is not rated for direct burial.
SER, on the other hand has no U in the cable designation, but it does have a W in the conductor designation. Bare aluminum can be installed in conduit in wet locations, and the conductors can also.
To be technical, I suppose that I should strip off the outer cable covering for the underground sections. That doesn't make a lot of sense, however, and, as someone else noted, I would worry about the bare aluminum ground corroding away without that outer SER covering.
Posted By: shortcircuit Re: type SER cable - 11/26/04 10:44 PM
Iwire asked: "Why use a cable if a raceway runs from point to point"?

The aluminum SER I saw stuffed into a 2" pvc pipe underground was installed in a pvc pipe that was only continuous from where it exited one building into an LB and entered the other building through another LB...the SER cable was unbroken from panel to panel and the PVC was used just for the underground section of the feeder...eliminating the need for a juction to change wiring methods.

I'm not saying it's OK...just an installation that I question?

When I 1st looked in article 338, I looked for the "Uses not permitted" part that I see in most other articles...maybe it needs to be added for 2008...

shortcircuit
Posted By: Roger Re: type SER cable - 11/26/04 10:47 PM
I agree with Bob, although I think there is a problem with SE and SER as far as the UL listings and NEC requirements.

Both of these say directly that SE and SER are for above ground use, yet the jacket of SE / SER will (unlike NM) identify the conductors inside which is XHHW or XHHW-2.

I don't know of anywhere in the NEC where THWN is specifically worded to be for "Above Ground Use"

The conductors of SE / SER wrapped in a PVC jacket would seem to be fine in an underground conduit if the two aforementioned inteties would not specifically say for "Above Ground Use"

This could be a conspiracy but there is no way around it. [Linked Image] [Linked Image]

Roger
Posted By: trekkie76 Re: type SER cable - 11/27/04 02:15 AM
tdhorne, I run 4 wire USE all the time, we call it trailer cable up here. Mostly for feeders to trailers from the pole. But I have to pose a question, what is the difference in terms of conditions, between the underground conduit and the side of the house the SE would be subject to? Lots of rain, snowload, and ice up my way, can't see how that would hurt the cable any less than being in the ground with the frost.
Posted By: earlydean Re: type SER cable - 11/27/04 01:13 PM
I believe the only reason for the designation: "above ground installation" is UL only tested it for "above ground installation", as the manufacturer only paid them to test it for "above ground installation".
The conductors in SE cables have XHHW insulation. XHHW insulation is OK to be installed in wet locations, and underground conduit is, by definition, a wet location.
Posted By: iwire Re: type SER cable - 11/27/04 01:28 PM
OK guys no where in my posts will you see that I say it will not work.

The problem comes down to the listing, for whatever reason SER is only listed for above ground use.

I agree it makes no sense but that is the situation.

If you use a product outside it's listing you have a 110.3(B) violation.

I sent out a number of emails asking questions about this thread and the responses I got all have the same basic opinion.

SE(R) will work fine installed underground. [Linked Image]

SE(R) installed underground is presently a NEC violation. [Linked Image]

Bob

[This message has been edited by iwire (edited 11-27-2004).]
Posted By: Joe Tedesco Re: type SER cable - 11/27/04 10:30 PM
Here's the 2004 UL White Book:
http://www.joetedesco.com/2004geninfo.pdf

I have helped to create many Code Scholars, so now everyone can become a Code Scholar too!

Have Fun!
Posted By: Bjarney Re: type SER cable - 11/27/04 11:02 PM
Joe—

Please take the rest of the day off with pay. I insist!

—Bjarn
Posted By: iwire Re: type SER cable - 11/27/04 11:13 PM
Joe Thanks for the updated UL book I will consider it my Christmas present. [Linked Image]

Everyone, I highly recommend taking advantage of Joe's link to the 2004 UL white book, it is not a great read [Linked Image] but it is a valuable resource.

If you have not seen one it contains info about products we install every day.

Conduit, breakers, fittings, baseboard heat, NM, you name it.

Joe emailed me my first white book, now I turn to it often.

Bob
Posted By: CTwireman Re: type SER cable - 11/28/04 02:03 AM
Code issues aside, it never made much sense to me to pull jacketed cable through conduit when pulling individual conductors is far easier. [Linked Image]
Posted By: RickG Re: type SER cable - 11/28/04 01:02 PM
Maybe I missed something, but what about the UNinsulated ground conductor inside the jacket of the SER cable? Is that rated to be in a underground location?
Rick
Posted By: earlydean Re: type SER cable - 11/28/04 04:25 PM
An underground location is by Article 100 definition a wet location. Look at: location, wet.
Posted By: iwire Re: type SER cable - 11/28/04 04:38 PM
Early I do not get your point.

THWN, RHW, XHHW, etc are all listed for wet locations.

However no where in their listings will you find the words for underground or above ground use.

IMO that leaves it up to us.

However you do find the words "cable for aboveground installation" in the listing for SE.

IMO that clearly tells us the cable is not for underground use.

They could have simply listed it as cable for wet locations but they did not.

Maybe a future code proposal is needed.

Bob
Posted By: earlydean Re: type SER cable - 11/28/04 09:48 PM
Just because UL says "cable for aboveground installation" doesn't mean it is not approved for use underground in conduit. It means UL tested it for aboveground use only, and they did not test it for underground in conduit use. It wasn't tested for use in a conduit in the ground because the manufacturer did not pay them to do that test.
Would you agree that it is OK to install SEU or SER on the outside of a building, sleeved in conduit? (Such as we see when we have a mast)
What possible extra harm could the SEU or SER come to when installed in conduit underground as opposed to aboveground?
The same argument could be offered for installing NM in conduit, which the 2005 NEC finally addressed. (it is allowed, but not underground because of the wet location)
I agree that a future code proposal is in order to clear this up.
Posted By: Redsy Re: type SER cable - 11/29/04 12:44 AM
The letter U in USE cable stands for underground.
However, the U in SE-U stands for "Unarmored".
I resurrected a thread from several years ago with an indepth discussion simliar to this thread.
I think the issue with SE-U installed undergroung is the uninsulated, albeit covered, aluminum neutral that is predominant in the Phila. area.
Posted By: earlydean Re: type SER cable - 12/04/04 01:14 AM
I asked this question of John Cangemi the answer man of UL. He stated in no uncertain terms that it would be a violation of the listing and the NEC to install SEU or SER underground.
I stand corrected, or rather, I stand with head bowed.
Posted By: shortcircuit Re: type SER cable - 12/04/04 01:33 AM
Thanx...I thought so.

shortcircuit
Posted By: iwire Re: type SER cable - 12/04/04 05:34 PM
early I do appreciate that you went to the source and I respect the fact you shared the answer with all of us even if it was not the answer you expected.

Believe me it has happened to me too.

Bob
Posted By: Joe Tedesco Re: type SER cable - 12/04/04 11:31 PM
Earl:

Glad that this issue has been cleared up.

Here's the 2004 UL Guide for Wire and Cable.
http://www.ul.com/regulators/mgwire.pdf

[Linked Image from joetedesco.com]
Posted By: earlydean Re: type SER cable - 12/05/04 12:57 AM
It would be dishonest of me to do otherwise.
Posted By: royta Re: type SER cable - 12/08/04 06:31 AM
The installation I was referring to was above ground, in EMT. [Linked Image]
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