Nec 314.28(a)(2)

[Mvillines]

After reading this thread and rereading 314.28 things seem to go together and make a lot more sense.

I am on the same page with Eric.

When the conductors are spliced the box dimensions are the same as un-spliced conductors, except the distance between conduits containing the spliced conductors is not required to be the six times distance. Example: If underground USE-2 conductors (USE-2 conductors are not listed to enter a building) enter a box that is located on an outside wall of a building and these conductors are spliced to THWN conductors to enter the building, I would consider these spliced conductors to be on the same circuit and phase but not consider them as the same conductor.

Its threads like this that keep my interest and keeps me hooked on this forum. Thanks everyone for great ideas and post. I?m amazed that I never thought of these NEC sections this way before.

 

[infinity]

Here's the code section:

314.28 Pull and Junction Boxes and Conduit Bodies.
Boxes and conduit bodies used as pull or junction boxes shall comply with 314.28(A) through (D).
(2) Angle or U Pulls, or Splices. Where splices or where angle or U pulls are made, the distance between each raceway entry inside the box and the opposite wall of the box shall not be less than six times the metric designator (trade size) of the largest raceway in a row. This distance shall be increased for additional entries by the amount of the sum of the diameters of all other raceway entries in the same row on the same wall of the box. Each row shall be calculated individually, and the single row that provides the maximum distance shall be used.
Exception: Where a raceway or cable entry is in the wall of a box or conduit body opposite a removable cover, the distance from that wall to the cover shall be permitted to comply with the distance required for one wire per terminal in Table 312.6(A).
The distance between raceway entries enclosing the same conductor shall not be less than six times the metric designator (trade size) of the larger raceway.
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.

If the conductors are spliced the 6X is still required or am I missing something?

 

[Pierre C Belarge]

I am not sure that I understand what the issue is????


Has anyone read the bold portion of the '08 in Section 314.28(A)(2)?

(A)(2) Angle or U Pulls or Splices.

 

[augie47]

Rob,
At best it's an alternate look at this sentance: "The distance between raceway entries enclosing the same conductor shall not be less than six times the metric designator (trade size) of the larger raceway."
The distance to the walls, etc. is 6X,8X etc., and if a conductor is pulled thru a box then, it being the "same condiuctor" the 6X between raceways applies. If the conductir is spliced, then its not the same conductor.
I'm not saying that interpretaion is right or wrong, just that it makes sense to me.

 

[erickench]

Infinity, that rule applies to the wall opposite the conduits entry. I'm talking about the other two walls. Here I updated my picture. See attachment. What is the distance of 'A'?

 

[Mvillines]

314.28(2) Angle or U Pulls, or Splices. Where splices or where angle or U pulls are made, the distance between each raceway entry inside the box and the opposite wall of the box shall not be less than six times the metric designator (trade size) of the largest raceway in a row.

Meaning where there are splices, U pulls, or angle pulls the distance between each raceway and the opposite wall is 6 times the conduit diameter. Not the distance between raceways. The distance between raceway entries is described in the paragraph below the exception enclosing the same conductors. When you splice conductors they are not the same conductors e.g. splicing copper to aluminum is splicing the same circuit but it does not make them the same conductor. Try telling the supply house they are the same conductor and buy copper conductors and pay aluminum prices.

Eric, my way of thinking is that if the wires are spliced dimension ?A? is not defined.

If I am wrong I going to blame all of you guy because I never though of this section this way until I read this post. (Just joking on blaming you guys, but you all do make one think)

 

[Pierre C Belarge]

I am assuming the conductors are 4 AWG or larger and the conduits are all 2 inches

6x2=12
+ 2
14
+ 2
16


A = 16 inches

 

[erickench]

Here's another update on the picture. Don't worry I'll get it right eventually.
The conduits are 3 inches diameter. Distance 'A' is between the two conduits.

 

[Mvillines]

I don't believe distance "A" is defined by the NEC.

 

[erickench]

No it is'nt. And the more I look at this the more I become convinced that it is'nt necessary to have a rule because it is a splice.

 

[infinity]

No it is'nt. And the more I look at this the more I become convinced that it is'nt necessary to have a rule because it is a splice.

So you're saying that a U pull would require the 6X distance between the raceways but a splice would not require the same 6X distance?

 

[don_resqcapt19]

So you're saying that a U pull would require the 6X distance between the raceways but a splice would not require the same 6X distance?

If you make a splice, is it still the same conductor? I don't think so. The space between raceways containing the same conductor are to help prevent pulling damage bending radius issues. Those are not issues when you splice the conductor.

However the code section is not really clear and many will contend that the splice makes one conductor out of 2 or more.

 

[erickench]

Yes it would appear so. Think of it this way. If the conduits are spaced at too large a distance, you might pull the splice apart.

 

[cowboyjwc]

deleated by poster

 

[mweaver]

? In regards to the Statement Don made in post #32 ??many will contend that the splice makes one conductor out of 2 or more ...?

?I find it interesting that this appears to be well defined in Section 314.16(B)(1), for smaller conductors,
but this appears to be undefined for insulated conductors of #4 & larger in Section 314.28(A)(2) ?

mweaver

 

[don_resqcapt19]

Yes it would appear so. Think of it this way. If the conduits are spaced at too large a distance, you might pull the splice apart.

"might pull the splice apart". I don't understand.

 

[erickench]

If you were to have two spliced conductors with the two conduits nearly touching each other this arrangement would not put a stress on the splice. If you have them too far apart you might cause separation if you were to use a cap.