?Bundling?

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JKinPA

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If there are several NM cables run on the top of a foundation next to the sill plate and they get cable tied (or large Romex staple) together and anchored to the sill plate is this considered bundling? They will be laying next to each other on top of the foundation but will not be closely tied together except for where the cable ties are. I know that to be considered bundling they have to be together for at least 24"...but how tightly do they have to be together for that 24"?
 
That is subject to interpretation by the AHJ. If you staple them or tie them every 4.5 feet as required by 334.30, I would consider them "bundled".
 
If you use stacker clips does this provide enough seperation to consider them not bundled.
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IMO, Yes. If you use romex stackers I would say you have just as much room between cables as if you stapled them right next to each other using separate staples.

I agree with haskindm, The AHJ has the final word on what they consider "bundled". I personally don't consider cables under the same staple to be "bundled" in regards to 310.15(B)(2). (Unless the staple is 2' long :D)

Chris
 
JKinPA said:
They will be laying next to each other on top of the foundation but will not be closely tied together except for where the cable ties are.
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If you can accomplish the above process then I would not considered it bundled. How would you keep them separate between ties? If you can keep them separated I do not see it as bundled. I just can't see how you could do keep them apart without stapling.
 
JKinPA said:
If there are several NM cables run on the top of a foundation next to the sill plate and they get cable tied (or large Romex staple) together and anchored to the sill plate is this considered bundling? They will be laying next to each other on top of the foundation but will not be closely tied together except for where the cable ties are. I know that to be considered bundling they have to be together for at least 24"...but how tightly do they have to be together for that 24"?
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I believe the key word is to "maintain" spacing. This is acheived by stack-its. :)
 
wbalsam1 said:
I believe the key word is to "maintain" spacing. This is acheived by stack-its. :)
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I agree with the maintain spacing but I am not sure you can keep that spacing with stackits. Stackits are design for vertical runs. If you use them horizontal they will sag and lay on top of each other. I am not sure they will work effectively.
 
Dennis Alwon said:
I agree with the maintain spacing but I am not sure you can keep that spacing with stackits. Stackits are design for vertical runs. If you use them horizontal they will sag and lay on top of each other. I am not sure they will work effectively.
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I agree. I have seen examples of this. I will amend my statement to this: This may be achieved by the use of stack-its where used in sufficient quantities and where used horizontally sagging of cables may be avoided through adequate spacing of stack-its. :cool:
 
I use stak-its for horizontal runs all the time, and your right they do sag, so I install them every 2' on center, I tried spacing them farther apart and use a tyrap here and there and the inspector made me cut them free and add more stak-its... go figure...:rolleyes:
 
Why is it you guys think stackers solve this?

310.15(2) Adjustment Factors.
(a) More Than Three Current-Carrying Conductors in a Raceway or Cable. Where the number of current-carrying conductors in a raceway or cable exceeds three, or where single conductors or multiconductor cables are stacked or bundled longer than 600 mm (24 in.) without maintaining spacing and are not installed in raceways, the allowable ampacity of each conductor shall be reduced as shown in Table 310.15(B)(2)(a).
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It's the 'Spacing' that is undefined and up to the AHJ - around here this equates to one cable diameter - depending on who you talk to. (I believe it was taken from cable tray spacing???) But if the code doesn't specify it, I think it is time they did...

Commentary from 334.80
Section 310.15(B)(2)(a) states in part: ?or where single conductors or multiconductor cables are stacked or bundled longer than 600 mm (24 in.) without maintaining spacing and are not installed in raceways, the allowable ampacity of each conductor shall be reduced as shown in Table 310.15(B)(2)(a).? Failure to comply with the appropriate adjustment ampacity derating called for by this table, where nonmetallic sheathed cables may be stacked or bundled, can lead to overheating of conductors.
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I have had the unfortunate circumstance to witness heating as described, and it was not too nice. Hot buttery sheath, and dried out insulation here and there.

Many of these products say they "address the spacing requirements" but how can they say that if the spacing requirements are not defined?
 
e57 said:
Why is it you guys think stackers solve this? ....
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I think the stack-its solve the problem because they "maintain" spacing when properly installed at proper intervals, etc. ......If bundled or stacked without maintaining....this would be the violation...:)
 
So proper "spacing" is 3/16" every 4'6"? Horizontally or vertically they do nothing to "maintain spacing" other than at the stacker itself, and as mentioned there is no defined "spacing" so how does 3M know what that is if we dont?

(Generally, I treat stacker runs as if they were conduit and stay below 9 CCC's per run)
 
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JKinPA said:
several NM cables run on the top of a foundation next to the sill plate
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I am not familiar with this type of construction. Why wouldn't this be in violation of 334.12(B)4.
 
chris kennedy said:
I am not familiar with this type of construction. Why wouldn't this be in violation of 334.12(B)4.
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I think the fact that it is in the crawl space or a basement says that it is not subject to excessive moisture. The sill plate is usually a 2x6 or 2x8 so the cables would be sitting on that. I don't see that as a violation. Bundling, yes, but not art 334. 12(B)(4)
 
e57 said:
So proper "spacing" is 3/16" every 4'6"? Horizontally or vertically they do nothing to "maintain spacing" other than at the stacker itself, and as mentioned there is no defined "spacing" so how does 3M know what that is if we dont?

(Generally, I treat stacker runs as if they were conduit and stay below 9 CCC's per run)
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All I can say is read the installation directions that come with them... if they don't require derating then so be it...
 
I believe that if you use a product like stack its or stakers you have achieved the intent of the code in this regard which is to use a "product". When you use such a product you are not bundling. If you do not spend the money and use a cheap product like a staple, then you are "bundling". Imho. Wish I could take the time to invent a product and get it listed. :roll:
 
I hate stack-its. They don't hold for spit.

If the AHJ were to call bundling on me for the installation described, I'd simply staple/zip tie 4 two-wire cables low, and 4 of them higher.
 
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