NM cable sleeved it conduit outdoors..

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ritelec

Senior Member
Location
Jersey
How about it?
As long as the raceway is big enough for it to fit twisted cables will bend around a sweep easier.

Yes, "the bend" is where I was going with that.

Not to mention removing a conductor or using it as a drag.

But I'm ok with the twist, twist, ..... Bedrock twist.

I'm also ok with nm in a conduit in a wet location.........although I don't and never have done it........it's too much of a pain in the ars #1, and I'm not sure where it fits into derateing being in a sheath and in a conduit.................

Twist, Twist...........Bedrock Twist.

http://www.youtube.com/watch?v=p96LiIQGBAg&feature=related


It's twitch.............never knew.

twitch, twitch......
 

iwire

Moderator
Staff member
Location
Massachusetts
Yes, "the bend" is where I was going with that.

Not to mention removing a conductor or using it as a drag.

But I'm ok with the twist, twist, ..... Bedrock twist.

I'm also ok with nm in a conduit in a wet location.........although I don't and never have done it........it's too much of a pain in the ars #1, and I'm not sure where it fits into derateing being in a sheath and in a conduit.................

Twist, Twist...........Bedrock Twist.

http://www.youtube.com/watch?v=p96LiIQGBAg&feature=related


It's twitch.............never knew.

twitch, twitch......

Are you related to Chicken Steve? :eek:hmy:
 

ritelec

Senior Member
Location
Jersey
Are you related to Chicken Steve? :eek:hmy:

Yes!!! You know Steve?!

We're third cousins twice removed.

We don't stay in touch to often, but did have a chance to catch up a bit at Aunt Mary's wake.


(she was 104 yrs old...........no joke there)
 

220/221

Senior Member
Location
AZ
Also I could never understand why you would use NMC in a conduit. Seems to me that it's just being lazy. Just pull wire in the conduit.


Simple. Splices are the most vulnerable failure points. It's not being lazy, it's being productive and not wasting resources.

On a simple installation, say a 24" stub from the attic to a floodlight under the eave it's one less Jbox and three fewer splices to fail. You have a nice stealthy installation that will never cause problems.

On a more difficult installation of a retrofitted exterior mounted service panel, every circuit (20-40?) would have to be spliced in a big assed Jbox changing to NM going into the attic structure?

That's silliness and serves no purpose. :)
 

peter d

Senior Member
Location
New England
You say lazy, I say efficient in many cases.

I want the wire makers to sell spools of THWN with black, white, green twisted together so they are like a little triplex. That would be nice for small pipe jobs.

That would be great and definitely come in handy a lot.
 

ritelec

Senior Member
Location
Jersey
That would be great and definitely come in handy a lot.

Agreed.

edit:

was thinking that you could "patent" the idea........but then was thinking, why not a 3 wire twisted or 4 wire twisted, with or without ground..............The manufacture would probably say get a
piece of pipe and pull off some reals......it would not be worth it to machine the process........

Nice thought though.....:thumbsup:
 
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220/221

Senior Member
Location
AZ
That would be great and definitely come in handy a lot.

I would hate it.

1. It's aint that much extra work to pull from 3 separate reels. Maybe if they put it on a single reel, untwisted.

2. The wires wouldn't pull in as cleanly

3. There would be no pulling one wire out to pull in others in rework. I couldn't even guess how many hundred times I've done that. Once in a while it fails because some clown taped his wires together.


4. Hi Peter !!
 

kwired

Electron manager
Location
NE Nebraska
How about it?

Tri plex is what a lot of power companies pull in underground conduits in my area.

As long as the raceway is big enough for it to fit twisted cables will bend around a sweep easier.

Triplexed conductos in larger sizes (usually aluminum) is common here usually for underground applications. Our suppliers have it with conductors with dual rated USE/RHW insuation so it can be used indoors. As has been said - they can make just about anything, Someone just needs to order it. These triplexed and quad plexed conductors generally are easier to handle and pull - but you do not want to have conduit bodies in the run unless it is just a short nipple through the wall to a panel from the conduit body - then you untwist the conductors for installing through the short section so movement of one conductor at a time is possible for the conduit body.

After reading Bob's comment it hit me that it's probably just the ground they are worried about in NMB so it can't be used in wet locations. It's not insulated.

If they made a type of cable with an insulated ground that would probably solve the problem and an outer covering that was sunlight resistant or we could just use UF cable.

The only problem with having black,white and green on a spool is that some people would complain about ahving to pull a ground ( waste money ) in EMT.

No kidding the multi-color spools sound like a good idea . I would probably try it to see how it worked out. And we could have another spool of black, white, red and green, and another spool of black, red, blue, white and green. And then someone would figure out that it was easier just to go back to having all the cable on sperate spools.

I am pretty sure I have seen ads in trade magazines before for assemblies like this - mostly targeting larger conductor sizes like would be commonly used for feeders and services.

I would hate it.

1. It's aint that much extra work to pull from 3 separate reels. Maybe if they put it on a single reel, untwisted.

2. The wires wouldn't pull in as cleanly

3. There would be no pulling one wire out to pull in others in rework. I couldn't even guess how many hundred times I've done that. Once in a while it fails because some clown taped his wires together.


4. Hi Peter !!

As I said before, for a raceway run conductors pull better than separate reels. You are effectively pulling one large cable and not 3 or 4 smaller ones. They will not get random twists and jam up they will act like one conductor. Conduit bodies and pull boxes can be a problem - pull boxes maybe not as much of a problem if you don't size them as small as possible.
 

LEO2854

Esteemed Member
Location
Ma
I would hate it.

1. It's aint that much extra work to pull from 3 separate reels. Maybe if they put it on a single reel, untwisted.

2. The wires wouldn't pull in as cleanly

3. There would be no pulling one wire out to pull in others in rework. I couldn't even guess how many hundred times I've done that. Once in a while it fails because some clown taped his wires together.


4. Hi Peter !!
I agree I don't see a need for that and it would be too much trouble to work with.
 

iwire

Moderator
Staff member
Location
Massachusetts
I would hate it.

Yet you have not tried it, makes sense. :p

1. It's aint that much extra work to pull from 3 separate reels.

You are right, it is not that much extra but it is extra and for those of use that don't drive such nice truck set ups as you space is a premium.

Maybe if they put it on a single reel, untwisted.

That would defeat the purpose.

2. The wires wouldn't pull in as cleanly

They would pull better, trust me on that. I have pulled a lot of twisted conductors into conduits, we often strip 20' - 30' of MC to pull trough a conduit into a panel. (We run MC through the suspended ceiling but have to change to pipe when we get to the open ceiling of the electrical room)

3. There would be no pulling one wire out to pull in others in rework.

That is a fact and there is no getting around that.
 
Not sure how to respond to this, my goal is not make you feel insulted but at the same time it is my personal opinion that following the code is professional and ignoring the code is unprofessional.

There have been times when I knowingly violated the code, when I have done so it has been unprofessional of me and I would not encourage others to follow that path. Our customers hire us over handymen presumably because we will follow the rules.
\

Thank you for your kind response. My attorney is reviewing the "The Code," and is only charging me $150 an hour, because, in her words, "The jargon is so familiar."
 

cowboyjwc

Moderator
Staff member
Location
Simi Valley, CA
\

Thank you for your kind response. My attorney is reviewing the "The Code," and is only charging me $150 an hour, because, in her words, "The jargon is so familiar."

I could of told you that for free.. :lol:

When I was coaching baseball I used to love when a parent would come up to me and tell me that they had taken their son to private lessons and were paying $60 an hour. I'd ask what the coach said and my usual response was, "that's what we've been telling little Johnny for two years now, hopefully at $60 an hour he'll listen.":lol:
 

jmellc

Senior Member
Location
Durham, NC
Occupation
Facility Maintenance Tech. Licensed Electrician
I sent an e-mail to Southwire to find out the ratings of the conductors used in NM-B cable..

It has been posted many times on a different forum nobody knew what the answer was..

From:Jeff Posey
Applications Engineer
Research Division
Southwire Company

"They are THHN/THWN but they are not designed to be used without the outer jacket. This is a dry location only product."

So the REAL reason is making money for the company and not public safety.. I rest my case.. :p

So they are THHN/THWN but not designed for use without an outer jacket. But a spool of THHN/THWN is designed for use without a jacket? Gets used that way all the time. Do they have a subgrade of THHN/THWN? I doubt it. It just isn't usually printed on the conductors that I've ever seen.
 

satcom

Senior Member
So they are THHN/THWN but not designed for use without an outer jacket. But a spool of THHN/THWN is designed for use without a jacket? Gets used that way all the time. Do they have a subgrade of THHN/THWN? I doubt it. It just isn't usually printed on the conductors that I've ever seen.

The THHN/THWN that is put in a jacket is UL tested as a cable assembly, and put under a series of tests to qualify the cable for wet location use.
 

B4T

Senior Member
So they are THHN/THWN but not designed for use without an outer jacket. But a spool of THHN/THWN is designed for use without a jacket? Gets used that way all the time. Do they have a subgrade of THHN/THWN? I doubt it. It just isn't usually printed on the conductors that I've ever seen.

It is the wet paper in the cable assembly that poses a clear and present danger to humans and pets.. in case you missed that post.. :slaphead:

We are suppose to follow code and don't ask questions when common sense tells you otherwise.. :eek:hmy:
 

peter d

Senior Member
Location
New England
The worst NM cable in conduit installation I have ever repaired was an U/G run of PVC to a pond receptacle. The conduit was completely submerged. I pulled out the NM cable and it was moldy and solidly wet, but surprisingly still intact. I replaced it with THWN/HN conductors of course. Yet I think NM cable is probably a lot more tolerant to moisture than we assume.
 
This thread reminds me of a situation I ran into in Denver a few years back.

A standard residential installation in those parts is to install an exterior panel and run all of the NM cables into the back of the panel through one or two 2" bushed KOs in the back of the panel (whether or not that is compliant is a subject for another thread...). We were doing a remodel job and for various reasons the best place to have the cables exit the home was under a window. We installed a 8" x 8" x 3' trough under the window. The cables came into the rear of the trough on the right and we set the panel on top on the left. We stripped the cable back where it came into the gutter and ran them into the panel through 2 2" x 4" nipples. The inspector failed the installation. He made us bring all of the wire back into the gutter and splice it to THWN conductors and then bring those into the panel.

Technically I guess he was correct but I couldn't really ever agree with the call. He had us install dozens of splices for 3' of wire, and the "suspect" conductors were outside anyway. It was the fact that we passed from one enclosure to another that caused the problem. In my opinion he made us compromise a superior installation in favor of a technicality. This was definitely an installation where I supported NM being able to be installed outdoors.
 

480sparky

Senior Member
Location
Iowegia
So they are THHN/THWN but not designed for use without an outer jacket. But a spool of THHN/THWN is designed for use without a jacket? Gets used that way all the time. Do they have a subgrade of THHN/THWN? I doubt it. It just isn't usually printed on the conductors that I've ever seen.

Well, THHN/THWN are not manufactured with an 'outer jacket', but they are certainly required to be installed with something around them..... 300.3 Conductors. (A) Single Conductors. Single conductors specified in Table 310.13(A) shall only be installed where part of a recognized wiring method of Chapter 3.

Southwire says their NM is made of THHN/THWN. But without any marking, it would be difficult to prove it to an inspector. Southwire cannot address how all manufacturers make their NM. Maybe your supply house has Essex, and they used THHN (or any other 90?C insulation) when they made their NM. So without solid proof your install actually does have W conductors, you get red-tagged.
 

B4T

Senior Member
Yet I think NM cable is probably a lot more tolerant to moisture than we assume.

I agree.. all I have seen so far is the CMP and manufacture getting together and telling us it is not safe being installed in a "wet location".. :slaphead:

The "wet location" is moisture and condensation that may accumulate inside of a closed raceway mounted above ground..

So far I have not seen any documentation that wet NM led directly to personal injury or death..

But take a plastic grocery bag from Stop & Shop.. bury it under (10) feet of wet dirt and it will last for hundreds of years..

Just keep this mind when your local town bans plastic shopping bags and mandates only paper bags.. :thumbsup:
 
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