# Use of stranded wire.



## zinsco1

310-3 states #8 or larger shall be standed. But it does'nt say # 8 or smaller can't be stranded. Is there a clear code reference thats denies the use of stranded wire in the smaller sizes ? I have recently been called on using stranded wire, even though i make pigtails for devices using fork terminals and a greenlee crimper. Small shop so pre-fab is a way of life for me. And out here the supplier i do business with has a back stock of stranded wire i'm getting it at killer price. In retrospect job specs always refer to 310-3 in the general notes. Seems black and white to me but could this reference be subject to interpretation? Any input would be greatly appreciated. Doug Larsen (Larsen Electric) Guam, USA


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## MDShunk

There is no code prohibition against it. Matter of fact, on commercial work, it would be difficult to find solid wire unless it was a small quantity purchased specially for receptacle circuits. There are some screw terminals that have a particular prohibition against stranded, but barring that, there's nothing anywhere against stranded in smaller gauges. Maybe a job spec.


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## Rockyd

Can't imagine NOT using stranded wire. It's capable of carrying more amps (more surface area), less likely to get damaged in a pull, easier to handle, and weighs less than solid wire. 

Ask where in the NEC that it says solid is better than stranded, not going to happen. Where in the spec's does it have a call out for solid?

The only place I actually like solid is on a device, then, even there, I think electrically, it's inferior to stranded.


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## raider1

> It's capable of carrying more amps (more surface area),


I know what you are trying to say, but would like to point out that small conductors like 10 and 12 AWG have the same ampacity, according to the NEC, whether or not they are stranded or solid.

Chris


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## Southeast Power

Solid wire is a bit cheaper by the roll than stranded wire. I was brought up in the trade using pipe and wire which was always 100% stranded.
I only encountered solid wire during residential service work. 
I still consider solid wire inferior for some reason.


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## JohnR

As solid is spec'd on every school I have worked on, I finally got a chance to ask an engineer why he kept speccing it.
His answer was that it was the only splice that ever held up on the 25 year test for tight splices without loosening or loosing integrity. 

Told him after that, that if he hadn't had a good answer, I was going to smack him for spec-cing in for no good reason.:whistling2:


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## Jlarson

Stranded is defiantly better. I've probably pulled miles of solid 14, 12, and 10 into conduit and that is no picnic. 

And you should have no problems landing stranded onto devices, most are UL listed for solid _or stranded_.


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## BBQ

Rockyd said:


> Can't imagine NOT using stranded wire. It's capable of carrying more amps (more surface area),





raider1 said:


> I know what you are trying to say, but would like to point out that small conductors like 10 and 12 AWG have the same ampacity, according to the NEC, whether or not they are stranded or solid.


A couple of points

There are air spaces in stranded meaning if the outside diameter remanded the same the ampacity would drop due to less copper.

Stranded conductors of the same AWG are larger than solid.

From table 8

12 AWG stranded 0.092" diameter

12 AWG solid 0.081" diameter


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## drsparky

The only solid I ever use is Cat 3 and 5. I don't do residential.


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## manchestersparky

When I was in the field I used solid on every project unless spe'd otherwise. In my area you'll see more solid then stranded. 
I hated using stranded myself


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## tates1882

zinsco1 said:


> 310-3 states #8 or larger shall be standed. But it does'nt say # 8 or smaller can't be stranded. Is there a clear code reference thats denies the use of stranded wire in the smaller sizes ? I have recently been called on using stranded wire, even though i make pigtails for devices using fork terminals and a greenlee crimper. Small shop so pre-fab is a way of life for me. And out here the supplier i do business with has a back stock of stranded wire i'm getting it at killer price. In retrospect job specs always refer to 310-3 in the general notes. Seems black and white to me but could this reference be subject to interpretation? Any input would be greatly appreciated. Doug Larsen (Larsen Electric) Guam, USA


 Did they provide a code ref?
#12 solid is the only way to go. #10 or larger stranded is easier to deal with.


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## macmikeman

I like pulling tw from the square cardboard boxes..........


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## Shado

macmikeman said:


> I like pulling tw from the square cardboard boxes..........


 Now you are bringing back some painful memories......especiallly when the box got wet and fell apart.


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## sparks134

macmikeman said:


> I like pulling tw from the square cardboard boxes..........


Don't tell me they still make those somewhere.

Dislike!


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## Voltech

Odd reading all the different views about this subject. We do lots of Govt work and it seems stranded is a major no no here. It also seems that most all other work in the area is the same now too. I think lots of the non govt work are using the same spec book more or less for every job, or generic version. I doubt I could go Monday morning and find more than a few rolls of stranded #12 from out top 3 SH...


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## Southeast Power

BBQ said:


> A couple of points
> 
> There are air spaces in stranded meaning if the outside diameter remanded the same the ampacity would drop due to less copper.
> 
> Stranded conductors of the same AWG are larger than solid.
> 
> From table 8
> 
> 12 AWG stranded 0.092" diameter
> 
> 12 AWG solid 0.081" diameter


Bob, We were taught that electrons flow along the surface for some reason. I would expect stranded conductors to have more surface area than solid.


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## brian john

JohnR said:


> As solid is spec'd on every school I have worked on, I finally got a chance to ask an engineer why he kept speccing it.
> His answer was that it was the only splice that ever held up on the 25 year test for tight splices without loosening or loosing integrity.
> 
> Told him after that, that if he hadn't had a good answer, I was going to smack him for spec-cing in for no good reason.:whistling2:



He is full of crap IMO, this spec is included because it was always there and the engineer is too lazy to remove it when he cuts and paste the spec into a new school.


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## Speedskater

jrannis said:


> Bob, We were taught that electrons flow along the surface for some reason. I would expect stranded conductors to have more surface area than solid.


Only at high frequency compared to the diameter of the wire.
For a 12AWG it starts above 20 kHz.
For a 2 inch diameter cable it's at 60 Hz.
As the frequency increases more and more current moves towards the surface.
Although it's caused by the wires self-inductance, the change is resistive.


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## mattsilkwood

I love solid wire. It works great for tying ladder and stuff down.:whistling2:


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## desar

stranded vs. solid If you looK in chapter 9 table 8 you'll see that their is a different resistance value for solid and stranded. Stranded wire when calculating voltage drop has a slightly higher resistance per 1000'.I know that voltage drop is not a code requirement and only a informational note, but if you have a specific peice of electronic equipment voltage drop could be important. The skin effect on these smaller wires is usually not a factor.


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## Shockdoc

I grew up with solid, and exclusively use solid. Stranded does not make as good of a termination as solid in my opinion.

Although I have used stranded in row lighting with 567 connectors.


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## DoCJohnny

Shockdoc said:


> I grew up with solid, and exclusively use solid. Stranded does not make as good of a termination as solid in my opinion.


That's funny, I have always felt that stranded makes a much better termination because it splays out under the lug or screw. More surface area, less resistance.


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## Shockdoc

DoCJohnny said:


> That's funny, I have always felt that stranded makes a much better termination because it splays out under the lug or screw. More surface area, less resistance.


I've seen solid sleeves for stranded as we used at CA as per the engineer spec when we terminated stranded, but I've also encountered numerous loose wirenut splices with stranded. In the rare time I've worked with stranded I used B crimps and nylon caps. I did'nt trust the wirenut.


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## desar

It's amazing how one question can spark such emotions and opinion.Is the use of stranded okay with everyone who opposes stranded wire with larger conductors but not smaller. Is it the way smaller conductors are terminated and spliced?


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## Wirenuting

Stranded or solid,,, they both have their uses and places. No one is better then the other for everything.


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## kaboler

I've only ever seen stranded coming into panels and such. The problem with stranded there is that if the guy 10 years ago knicked the conductor, those strands can snap off. I've seen it, and it is probably a reason why panels melt down.

I think it'd be cool to have 3/0 solid and instead of having it go into a panel with a lug, it could go into a panel with some kind of constricting jacket so it can form a solid connection. Hard to bend.

Maybe the real reason for stranded above a certain level is stiffness of pulling. If you've had to pull 8 solid through an EMT box, it'd probably not bend good at all, and peel a lot of the insulator off.

As for stranded in say, 12awg, I think it's better, except (like that dude at the school said) if you ever have to take the strand apart, and add a circuit, it sucks.


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## Wirenuting

kaboler said:


> .
> 
> I think it'd be cool to have 3/0 solid and instead of having it go into a panel with a lug, it could go into a panel with some kind of constricting jacket so it can form a solid connection. Hard to bend.


Man I've worked with old, WW2 era large Gage solid. It sucks 100%. It was a steel/copper hybrid wire. Lasts forever but not worth the man power to install or maintain.


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## Rockyd

kaboler said:


> I've only ever seen stranded coming into panels and such. The problem with stranded there is that if the guy 10 years ago knicked the conductor, those strands can snap off. I've seen it, and it is probably a reason why panels melt down.


Guess again. Panel melt downs are not hat common, and they melt down for a variety of reasons. Loose bus work, improperly installed conductors, etc. I don't think wires with a "haircut" cause many "meltdowns".



> I think it'd be cool to have 3/0 solid and instead of having it go into a panel with a lug, it could go into a panel with some kind of constricting jacket so it can form a solid connection. Hard to bend.


You need to smacked with a 3/4" hickey for entertiaining such an evil thought .....



> Maybe the real reason for stranded above a certain level is stiffness of pulling. If you've had to pull 8 solid through an EMT box, it'd probably not bend good at all, and peel a lot of the insulator off.


Try considering stress relief of the insulation and condutor after it's installed....



> As for stranded in say, 12awg, I think it's better, except (like that dude at the school said) if you ever have to take the strand apart, and add a circuit, it sucks.


The "dude" is another apprentice. Be still and pay attention to your JW, you'll learn a lot more from him, than your school mate. There's a reason JW's make more than App's...


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## BBQ

kaboler said:


> I've only ever seen stranded coming into panels and such.* The problem with stranded there is that if the guy 10 years ago knicked the conductor, those strands can snap off.*


Really? 




> I've seen it, and it is probably a reason why panels melt down.


I know I am just another annoying J-man but I am 46 now and have had a paying job in this trade since I was 17. So _maybe_ I have seen one or two more panels than you have.

Of the panels I have seen that have 'melted down' few of them had anything at all to do with the conductors.




> I think it'd be cool to have 3/0 solid


Which proves you have no freaking clue at all. 






> Maybe the real reason for stranded above a certain level is stiffness of pulling.


You figured that out on your own? :laughing:

I work with 500, 600, sometimes 750 kcmil, I am glad they are stranded.




> As for stranded in say, 12awg, I think it's better, except (like that dude at the school said) if you ever have to take the strand apart, and add a circuit, it sucks.


Your lack of knowledge and abilities is outstanding. :laughing:


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## kaboler

Hey BBQ, whatever.


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## The_Modifier

kaboler said:


> Hey BBQ, whatever.


Hahahaha you're so funny. Well at least your assumptions are. :thumbsup:


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## cultch

Searched stranded and this came up. I didn't think there was a code prohibiting stranded on devices. I am correct on that yes? It comes down to the device...does it accept stranded or no...correct?

We are doing a renovation and stranded is there at the receptacles. They are telling me no stranded on devices so pig tail or crimp. No problem I'll do whatever but I hate being told something is against code when it is not.

btw I didn't chirp too loud...sorta said...huh....came home to read up.

So if your renovating a job and nothing is in the specs about stranded/solid...and stranded is there....woudn't you just land the stranded on the new devices?


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## BBQ

As far as I know all 15, 20 and 30 amp devices for use in standard boxes are listed for use with either solid or stranded.


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## user4818

BBQ said:


> As far as I know all 15, 20 and 30 amp devices for use in standard boxes are listed for use with either solid or stranded.


P&S residential grade devices have "Solid copper wire only" stamped on them, though this might be referring to the push-in connectors only, not the screw terminals.


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## cultch

Shunk said something in the 2nd post of this thread about certain screw terminal not accepting stranded...Something for the office to get straight.

I just think the m/o is a little waste of time here. The panel is labled nicely and it's close. (dorms) Find breaker kill circuit. Demo receptacle (cutting the wire saving the crimp that's already on the ground). At that point I would walk away but they have the guys splicing the wires back together/wrienutting and later on we have to pigtail or crimp when trimming out. I wanted to take one wire off the breaker and wirenut it instead of all the wirenuts at the receptacle for safety but they like wasted effort and I am paid by the hour but I could probably be paid MORE by the hour if they thought this stuff through.

Anyway I knew I'd find something on et about it...thanks et...


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## wendon

We use stranded with crimps all the time. Much easier to pull. Much easier to fit in the box with the device.


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## Timofee

Here in Oz, all we ever use is stranded. A few domestic blokes use solid 1mm for lighting, but these days, it's pretty much stranded everywhere


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