Contradiction Yea or Nay

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Dennis Alwon

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Here is an interesting contradiction. Table 9 Note #2 states

2) Table 1 applies only to complete conduit or tubing systems and is not intended to apply to sections of conduit or tubing used to protect exposed wiring from physical damage.

Now go to 312.5(C)

(C) Cables. Where cable is used, each cable shall be secured to the cabinet, cutout box, or meter socket enclosure.
Exception: Cables with entirely nonmetallic sheaths shall be permitted to enter the top of a surface-mounted enclosure through one or more nonflexible raceways not less than 450 mm (18 in.) and not more than 3.0 m (10 ft) in length, provided all of the following conditions are met:

(G)Where installed as conduit or tubing, the allowable cable fill does not exceed that permitted for complete conduit or tubing systems by Table 1 of Chapter 9 of this Code and all applicable notes thereto.
FPN: See Table 1 in Chapter 9, including Note 9, for allowable cable fill in circular raceways. See 310.15(B)(2)(a) for required ampacity reductions for multiple cables installed in a common raceway.
This seems to contradict Note 2 or am I missing something here.
 

charlie b

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It's not a contradiction. 312.5(C) is merely taking advantage of an available table that is used for other purposes, and that applies in an set of circumstances that are unrelated to 312.5(C).

It is not unlike (I hope I get this right) table 250.66. It applies to a specific type of installation (GECs). But I believe that there are other places in the code (please don't ask me to name any of them) that say to size the wire per table 250.66. You are sizing a bonding jumper of some sort or other, and you are told to size it as though it were a GEC, which it is not.
 

charlie b

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Let me add (since I have somehow fallen behind you in post count ;) ) that when 312.5(C) sends you to table 1, it includes "all applicable notes thereto." In this case, note 2 would not be "applicable."
 

Dennis Alwon

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Let me add (since I have somehow fallen behind you in post count ;) ) that when 312.5(C) sends you to table 1, it includes "all applicable notes thereto." In this case, note 2 would not be "applicable."
That was exactly what I was referring to so what is the purpose of 312.5(G) --
 

al hildenbrand

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Here is an interesting contradiction. Table 9 Note #2 states
.
.
Now go to 312.5(C)
(C) Cables. Where cable is used, each cable shall be secured to the cabinet, cutout box, or meter socket enclosure.
Exception: Cables with entirely nonmetallic sheaths shall be permitted to enter the top of a surface-mounted enclosure through one or more nonflexible raceways not less than 450 mm (18 in.) and not more than 3.0 m (10 ft) in length, provided all of the following conditions are met:

(g)Where installed as conduit or tubing, the allowable cable fill does not exceed that permitted for complete conduit or tubing systems by Table 1 of Chapter 9 of this Code and all applicable notes thereto.
FPN: See Table 1 in Chapter 9, including Note 9, for allowable cable fill in circular raceways. See 310.15(B)(2)(a) for required ampacity reductions for multiple cables installed in a common raceway.
This seems to contradict Note 2 or am I missing something here.
Doesn't "and all applicable notes thereto" give the relief you are looking for? I mean, it seems to me that that phase provides the way to include the exception for short sections used for physical protection.

And I note that Charlie just added this, as well. :)
 

Dennis Alwon

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It's not a contradiction. 312.5(C) is merely taking advantage of an available table that is used for other purposes, and that applies in an set of circumstances that are unrelated to 312.5(C).

It is not unlike (I hope I get this right) table 250.66. It applies to a specific type of installation (GECs). But I believe that there are other places in the code (please don't ask me to name any of them) that say to size the wire per table 250.66. You are sizing a bonding jumper of some sort or other, and you are told to size it as though it were a GEC, which it is not.

I understand what you said in the second paragraph but I do not see what that has to do with the situation I presented. :)
 

al hildenbrand

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That was exactly what I was referring to so what is the purpose of 312.5(G) --
I would suggest making it harder for a DIYer to indulge in the disturbingly common practice of pulling NM into complete conduit systems.
 

Dennis Alwon

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I wasn't looking for relief I was just wondering what the purpose of 312.5(G) is if it is negated in Chapter 9. That is where I see the contradiction. One section says to use the table fill then the other part states no need to. :confused:

I am curious if (G) meant to say when installed as complete raceway see Chapter 9. I may submit yet another proposal. :)
 

al hildenbrand

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One section says to use the table fill then the other part states no need to. :confused:
I think one section says use the table fill if the notes require it, and then one of the notes says you don't need to use the table fill for short sections of raceway used for physical protection.

I honestly don't see the contradiction.
 
I wasn't looking for relief I was just wondering what the purpose of 312.5(G) is if it is negated in Chapter 9. That is where I see the contradiction. One section says to use the table fill then the other part states no need to. :confused:

I am curious if (G) meant to say when installed as complete raceway see Chapter 9. I may submit yet another proposal. :)

Dennis
I am not sure what this issue is you are having with the wording.

312 is referencing Chap 9 and the notes to the tables. Not all of the notes are applicable to all installations.
 

Dennis Alwon

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Dennis
I am not sure what this issue is you are having with the wording.

312 is referencing Chap 9 and the notes to the tables. Not all of the notes are applicable to all installations.

Pierre 312.5(C)(g) has to be met in order to use the except. (g) states that we must consider fill- I am assuming we are talking about fill on a 18" long piece of conduit used as a sleeve providing a-g is met.

Again (g) state consider fill but Table 1 doesn't apply to sleeves. Is that not a contradiction. Consider fill but don't consider it. I think (g) is meaning when conduit is used as a complete raceway but does not say it.
 

al hildenbrand

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Minnesota
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Pierre 312.5(C)(g) has to be met in order to use the except. (g) states that we must consider fill- I am assuming we are talking about fill on a 18" long piece of conduit used as a sleeve providing a-g is met.

Again (g) state consider fill but Table 1 doesn't apply to sleeves. Is that not a contradiction. Consider fill but don't consider it. I think (g) is meaning when conduit is used as a complete raceway but does not say it.
No, actually it DOES say "complete conduit or tubing systems".
(g)Where installed as conduit or tubing, the allowable cable fill does not exceed that permitted for complete conduit or tubing systems by Table 1 of Chapter 9 of this Code and all applicable notes thereto.
FPN: See Table 1 in Chapter 9, including Note 9, for allowable cable fill in circular raceways. See 310.15(B)(2)(a) for required ampacity reductions for multiple cables installed in a common raceway.
Note 2 to Table 1 says definitively that a physical protection use of conduit or tubing NOT a complete conduit or tubing system.

312.5(C)Exception(g) seems consistent. I don't find the conflict, or contradiction.

Basically, Ch. 9 Table 1 Note 2 reminds one that Table 1 applies to complete systems, not to sections used for a sleeve and/or physical protection.
 
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Dennis Alwon

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The entire section in 312.5 relates to a sleeve and wires entering a sleeve. They must meet the criteria. (g) should not be a criteria since a sleeve does not need to be considered for fill. It is basically saying use the table that is for complete raceways but the note to the table says not necessary to use the table for sleeves. It's ridiculous IMO.
 

mbeatty

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Illinois
The entire section in 312.5 relates to a sleeve and wires entering a sleeve. They must meet the criteria. (g) should not be a criteria since a sleeve does not need to be considered for fill. It is basically saying use the table that is for complete raceways but the note to the table says not necessary to use the table for sleeves. It's ridiculous IMO.

Based on how I read it, I agree with Dennis.
Regards,
Mark :)
 
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