# Max current carrying conductors



## NolaTigaBait (Oct 19, 2008)

There is no "max" so to speak, if you have too many, a #10 thhn may only be good for 15 amps etc....Check 310.15b2


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## Big City Electrician (Jul 5, 2010)

That's how I do my 20 amp receptacle circuits in commercial, I pull 20 #10's in a 1 1/4" EMT to a big, centrally located J-Box and from there take off with #12 MC's...


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## raider1 (Jan 22, 2007)

pesdfw said:


> What is the max number of current carrying conductors allowed in a wireway? I believe it's 30, but I can't find it in the code book to be sure.


That is the maximum you can have in a wireway without derating the conductors.

Check out 376.22(B) (2008 NEC)

If you install more than 30 at any cross sectional area of the wireway you must adjust the ampacity in accordance with 310.15(B)(2)(a).

Chris


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## Bkessler (Feb 14, 2007)

If you install more than nine current carrying conductors you must derate. Actually after 3 but it usually only effects raceways after nine.


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## NolaTigaBait (Oct 19, 2008)

Big City Electrician said:


> That's how I do my 20 amp receptacle circuits in commercial, I pull 20 #10's in a 1 1/4" EMT to a big, centrally located J-Box and from there take off with #12 MC's...


The guy I worked for did mostly resi...He did a commercial buildout,,,He ran a piece of 2'' and stuffed it with like 100 wires and hit a huge jbox and ran mc out of that...:laughing:


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## Big City Electrician (Jul 5, 2010)

NolaTigaBait said:


> The guy I worked for did mostly resi...He did a commercial buildout,,,He ran a piece of 2'' and stuffed it with like 100 wires and hit a huge jbox and ran mc out of that...:laughing:


LOL, at some point you have to wonder if a sub panel might be a better idea...


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## raider1 (Jan 22, 2007)

Bkessler said:


> If you install more than nine current carrying conductors you must derate. Actually after 3 but it usually only effects raceways after nine.


Did you read the code section I referenced?:001_huh:

For wireways you are permitted to install up to 30 CCC's before you are required to comply with 310.15(B)(2)(a).

Again take a look at 376.22(B) (2008 NEC)

Chris


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## Bkessler (Feb 14, 2007)

Were on 2005, and by book is in my truck but I suspect that I am right and your wrong. You should mention that to big city too, that we he doesn't have to keep stuffing 20 #10's in an 1-1/4".


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## jwjrw (Jan 14, 2010)

Bkessler said:


> Were on 2005, and by book is in my truck but I suspect that I am right and your wrong.
> 
> 
> 
> ...


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## Big City Electrician (Jul 5, 2010)

376 Does not apply to conduit. It applies to "Sheet metal troughs with hinged or removable covers".


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## jwjrw (Jan 14, 2010)

Big City Electrician said:


> 376 Does not apply to conduit. It applies to "Sheet metal troughs with hinged or removable covers".


 

We were talking about wireways....:whistling2:


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## raider1 (Jan 22, 2007)

Bkessler said:


> Were on 2005, and by book is in my truck but I suspect that I am right and your wrong.


Try again A-hole.:laughing:

Check out 2005 NEC 376.22.

"The derating factors in 310.15(B)(2)(a) shall be applied only where the number of current carrying conductors, including neutral conductors classified as current carrying under the provisions of 310.15(B)(4), exceeds 30."

Again the OPer is asking about wireways.

Chris


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## Bkessler (Feb 14, 2007)

Big City Electrician said:


> 376 Does not apply to conduit. It applies to "Sheet metal troughs with hinged or removable covers".


Gracias mi amigo, trying to put 30 ccc in one pipe would look like a monkey ****ing a football!

What movie Big City?


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## Bkessler (Feb 14, 2007)

raider1 said:


> Try again A-hole.:laughing:
> 
> Check out 2005 NEC 376.22.
> 
> ...


I see, were both right then.:laughing: cept I am an ahole.:laughing:


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## Big City Electrician (Jul 5, 2010)

I'm an A-hole too! The movie quote is from Stripes with Bill Murray.


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## raider1 (Jan 22, 2007)

Bkessler said:


> I see, were both right then.:laughing: cept I am an ahole.:laughing:


Yep we are both right you are an A-hole.:laughing:

Chris


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## raider1 (Jan 22, 2007)

Big City Electrician said:


> I'm an A-hole too! The movie quote is from Stripes with Bill Murray.


LOL:laughing::laughing::laughing:

Very funny movie.

Chris


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## jwjrw (Jan 14, 2010)

raider1 said:


> LOL:laughing::laughing::laughing:
> 
> Very funny movie.
> 
> Chris


 

Thats the FACT JACK!!


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## Bkessler (Feb 14, 2007)

it's true, I once got a fortune cookie that said "your a complete and total asshole", it was written in ink on the back side of the real fortune but I think it was spot on.

and the line was Herb Brooks, in Miracle. At least that's the one I was thinking.


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## NolaTigaBait (Oct 19, 2008)

I just realized we are talking about wireways:blink:...Damn, I'm an asshole.


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## Bkessler (Feb 14, 2007)

NolaTigaBait said:


> I just realized we are talking about wireways:blink:...Damn, I'm an asshole.


Dark Helmet: Careful you idiot! I said across her nose, not up it! 
Laser Gunner: Sorry sir! I'm doing my best! 
Dark Helmet: Who made that man a gunner? 
Major Asshole: I did sir. He's my cousin. 
Dark Helmet: Who is he? 
Colonel Sandurz: He's an asshole sir. 
Dark Helmet: I know that! What's his name? 
Colonel Sandurz: That is his name sir. Asshole, Major Asshole! 
Dark Helmet: And his cousin? 
Colonel Sandurz: He's an asshole too sir. Gunner's mate First Class Philip Asshole! 
Dark Helmet: How many asholes do we have on this ship, anyway? 
[Entire bridge crew stands up and raises a hand] 
Entire Bridge Crew: Yo! 
Dark Helmet: I knew it. I'm surrounded by assholes! 
[Dark Helmet pulls his face shield down] 
Dark Helmet: Keep firing, assholes!


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## NolaTigaBait (Oct 19, 2008)

Spaceballs... nice.


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## raider1 (Jan 22, 2007)

NolaTigaBait said:


> Spaceballs... nice.


:thumbsup:

Chris


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## Bob Badger (Apr 19, 2009)

Ya gotta do it right .........:thumbsup:


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## Mike in Canada (Jun 27, 2010)

Just as an interesting aside, I'm working on a project right now where I have pulled the conductors for 15 motors through a 2" EMT conduit. I had to derate down to 30% or so, as I recall, but the motors are only a couple of horsepower at 600V, so the 14 gage THHN has no problem supplying that.
That's 45 current carrying conductors through 140' of 2" EMT. No problem.

Mike


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## McClary’s Electrical (Feb 21, 2009)

Mike in Canada said:


> Just as an interesting aside, I'm working on a project right now where I have pulled the conductors for 15 motors through a 2" EMT conduit. I had to derate down to 30% or so, as I recall, but the motors are only a couple of horsepower at 600V, so the 14 gage THHN has no problem supplying that.
> That's 45 current carrying conductors through 140' of 2" EMT. No problem.
> 
> Mike


 

I saw a very large fan shed that had (32) 3 phase fan motors on each side of the building for drying lumber. They had (125) 14's in one conduit (some were spares but not many)


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## romexican (Jul 22, 2010)

Mike in Canada said:


> Just as an interesting aside, I'm working on a project right now where I have pulled the conductors for 15 motors through a 2" EMT conduit. I had to derate down to 30% or so, as I recall, but the motors are only a couple of horsepower at 600V, so the 14 gage THHN has no problem supplying that.
> That's 45 current carrying conductors through 140' of 2" EMT. No problem.
> 
> Mike


What type of OCPD are you using that will limit the conductors to 7.5 amps? Or does it not matter since you know exactly what the load connected to them is?


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## Mike in Canada (Jun 27, 2010)

romexican said:


> What type of OCPD are you using that will limit the conductors to 7.5 amps? Or does it not matter since you know exactly what the load connected to them is?


 They're all motors and all fused and running on motor starters (i.e. with overload packs). I'm not worried. The aux conduits are actually more worrisome. They have about 80 conductors each. They're small potatoes, power-wise, but the expected draw is immaterial if you get a dead short, eh?

Mike


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## pesdfw (Jun 23, 2010)

raider1 is right ... thanks for the feedback ... now it's time to go fix another electricians screw up!


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