Box sizing

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Vertex

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What is the minimum size box required for splicing two #4/2 SE cables? Please cite NEC reference.
 
Vertex said:
What is the minimum size box required for splicing two #4/2 SE cables? Please cite NEC reference.
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Check the last paragraph of 314.28 (it is the one after the exception to 314.28(2)


When transposing cable size into raceway size in
314.28(A)(1) and (A)(2), the minimum metric designator
(trade size) raceway required for the number and size of
conductors in the cable shall be used.
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iwire said:
Check the last paragraph of 314.28 (it is the one after the exception to 314.28(2)
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Thank you, Bob. I've read through this sections several times before asking. I still need some clarification.

If I am interpreting this correctly, a calculation must be done to determine what size raceway would theoretically accommodate the conductors. If so, how would I find the area of the conductors? I don't think the area for SE cable is listed in the NEC. Also, no specific raceway is mentioned.

Is it just me or is this section a little bit ambiguous?
 
Truthfully I have never put much thought into it, I tend to oversize boxes but yeah it seems a bit hard to nail down if you where being tested on it.
 
As I read 314.28 it states for cables or raceways. Iguess you would use the connector size for the cable.

For straight pulls

ry%3D400


For U Pulls

ry%3D400


For angle pulls

ry%3D400
 
I'm thinking you would need a min of 1 1/4 pipe (you can only get 2 in 1") conduit so if the cables go in oposite ends of box it needes to be 8 times that or 10" long
 
S'mise said:
I assume the answer to his question is; one cable in and one out.

Next question to ask is; where is the cables entering the box?
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But you need to know what size conduit you need for the wires , in this case probable 1-1/4 or 1-1/2 then size your box based on the location of the cables (straight or angle pull).
 
Why would there be four #2 and one #8 in each raceway? The OP is trying to splice two 4/2 SE cables. Each cable would contain three #4 XHHW conductors or possibly two #4 and one #6 conductors. You use the equivalent raceway size for each cable not for all the conductors in all the cables. Three #4 XHHW conductors can easily fit into a 1" raceway.

All SE cable I have seen has contained XHHW conductors.
 
I don't like the idea of making assumptions, but let's assume the following for the sake of argument;

One cable in and one cable out (position in box irrelevant)
Both SE cables are 4/2 w/ #6 bare ground
Insulated conductors are type XHHW
Theoretical conduit to be considered is EMT

Based on my calculations, the minimum conduit size is 3/4".
Minimum box size is 4-1/2" square (A 4-11/16" square box would work)

Before making any condemnations, please understand that I have not advocated using the minimum standard for this application.
 
iwire said:
BTW, I like the signature.
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My quote is "tongue-in-cheek" expression regarding America. I believe it parallels the concept of "bread and circuses".


Here's a history lesson.
http://en.wikipedia.org/wiki/Bread_and_circuses

Here's a video of the song.
http://www.youtube.com/watch?v=dVGINIsLnqU&ob=av2e

Here's the lyrics.
We're victims of sedition on the open sea
No one ever said life was free
Sank, swam, go down with the ship
Just use your freedom of choice

I'll say it again in the land of the free
Use your freedom of choice
Freedom of choice

In ancient Rome there was a pawn
Who followed along and watched it fall
He cast a stone, he felt secure
He felt that he would never be heard

Freedom of choice
Is what you got
Freedom of choice

You're given a voice you don't want it
Seems to be the rule of thumb
Don't be tricked by what you see
You got two ways to go

I'll say it again in the land of the free
Use your freedom of choice
Freedom of choice

Freedom of choice
Is what you've got
Freedom of choice

In ancient Rome there was a pawn
Who followed along and watched it fall
He cast a stone, he felt secure
He felt that his voice would never be heard

Freedom of choice
Is what you've got
Freedom from choice
Is what you want

Freedom of choice
Is what you've got
Freedom from choice
Is what you want

Freedom from choice
Is what you want
Freedom from choice

~Devo
 
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