Bundling ?
- Thread starter augie47
- Start date
- Status
levjo
Member
- Location
- massachusetts
yes yes yeeees....
yes yes yeeees....
Yes it is. General rule of thumb is no more than 8 ... Also communications wires in long runs next to current carrying wires could cause interference...
yes yes yeeees....
Yes it is. General rule of thumb is no more than 8 ... Also communications wires in long runs next to current carrying wires could cause interference...
north star
Senior Member
- Location
- inside Area 51
= = ( | ) = =
Yes !.....Refer to Section E3605.3, in the `06 IRC. :happyyes:
= = ( | ) = =
Yes !.....Refer to Section E3605.3, in the `06 IRC. :happyyes:
= = ( | ) = =
- Occupation
- Licensed Electrician
You could have a very similar pic if you had been at my house when I remodelled it. 2001 was when I roughed in. Everything is still working. Nothing to worry about. I don't even think about it except when discussions about bundling come up.
hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
Per the words written in the NEC yes, but as installed per the intent of the code NO, the problem is no one has ever done any real world test to show any danger in a run like that in the photos, the diversity of the usage of those conductors in a dwelling would never cause enough heat to ever damage the insulation of those conductors as long as they are not in an insulated cavity or outside wall or roof or attic space where they would be subject to higher temps.
Back in 2004 I made a proposal that Charlie Eldridge also helped me with who was also on CMP 10, while it didn't make it because I didn't run thousands of dollars in test to prove my point, many agreed with me.
Here is the old thread I started for that proposal which explains my feelings on this:
310.15(B)(2) add Exception 6.
This was for the changes to the 2002 for the 2005 code cycle.
Back in 2004 I made a proposal that Charlie Eldridge also helped me with who was also on CMP 10, while it didn't make it because I didn't run thousands of dollars in test to prove my point, many agreed with me.
Here is the old thread I started for that proposal which explains my feelings on this:
310.15(B)(2) add Exception 6.
This was for the changes to the 2002 for the 2005 code cycle.
Last edited:
grizwald
Member
- Location
- California
So, how do you feel about spray in insulation? That is a little different; it creates a situation similar to conduit...or conductors bundled for +24"...
- Location
- Massachusetts
To the AHJs around me that is bundling.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Well, spacing is being maintained. It is just close to zero spacing.
Tapatalk!
Tapatalk!
fmtjfw
Senior Member
- Location
- Fairmont, WV, USA
310.15(B)(3)(a) [2014]
310.15(B)(3)(a) [2014]
310.15(B)(3)(a) More Than Three Current-Carrying Conductors.
Where the number of current-carrying conductors in a raceway
or cable exceeds three, or where single conductors or
multiconductor cables are installed without maintaining spacing
for a continuous length longer than 600 mm (24 in.) and
are not installed in raceways, the allowable ampacity of each
conductor shall be reduced as shown in Table 310.15(B)(3)(a).
Each current-carrying conductor of a paralleled set of conductors
shall be counted as a current-carrying conductor.
310.15(B)(3)(a) [2014]
310.15(B)(3)(a) More Than Three Current-Carrying Conductors.
Where the number of current-carrying conductors in a raceway
or cable exceeds three, or where single conductors or
multiconductor cables are installed without maintaining spacing
for a continuous length longer than 600 mm (24 in.) and
are not installed in raceways, the allowable ampacity of each
conductor shall be reduced as shown in Table 310.15(B)(3)(a).
Each current-carrying conductor of a paralleled set of conductors
shall be counted as a current-carrying conductor.
mjf
Senior Member
About two or three years ago we had a seminar at out IAEI meeting regarding cable bundling. There was a gentleman from Vegas (I can't think of his name), but his company did the testing on bundling ... and the outcome was very high temperatures especially in the middle of the bundle.
But it all depends to what amperage and for how long do the cables carry the load. Usually in a residential setting the cables don't see the full current carrying capacity for very long. Even though it is a bundling violation but in real world it won't be a problem.
But it all depends to what amperage and for how long do the cables carry the load. Usually in a residential setting the cables don't see the full current carrying capacity for very long. Even though it is a bundling violation but in real world it won't be a problem.
hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
Temperature rise created in wire from current flow is an additive to the ambient temp, so conductors will rise in addition to any ambient heat as well, if the insulation does not allow the heat from current to transfer to the air surrounding the conductors you could have heat build up depending upon how much and how many of the cables are loaded, this is very similar to the problem with motors and transformers, lets say a motor has a 45?c rise in temp when running close to its FLA, if the ambient is around 30?c this would not be a problem but put the motor in a 75?c environment and you can see you now have a problem of the motor running at a temp of 120?c unless it is design for it.
Now for your question, most of these types of installations are in cool basements, if a little over spray were to get on the NM I would not have any worries as the conductors would not be loaded that would cause much heat to start with, but again in areas such as attics and outside walls where the conductors would also most likely be embedded in insulation and with the sun bearing down on the roof or wall the ambient temp surrounding the wire could be high enough to cause insulation failure of the wire, common sense would be a very important tool here in jugging this type of installation, my proposal didn't get in to the NEC but Charlie did submit it to the state of Indiana where it did pass, so at least for our state we have some relief.
In my experience of 40 years, I have not seen damaged NM in a dwelling where conductors were bundled as shown in the above photos, where I have seen a problem is in attics or commercial jobs where the conductors are more likely to have more load on more conductors, or where the ambient temp is much higher in the area around the wire, and or it is embedded in insulation.
Last edited:
stew
Senior Member
- Location
- federal way,washington
3 in a hole here in Wa or it wont fly.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Is that an amendment? You can actually have 4 - 2 wire nm cables without derating changing the ampacity.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
I did a job years ago where I laid the nm cables in the attic near the roof line. Every 4 feet or so I used a tie wrap to tie the cables together and stapled one of the cables. The entire run the wires were separated except where they were tied-- inspector called it bundling. I asked him about the exact situation that Gus presented in this thread and he said- I never thought about it like that. They never considered it bundling till then.
If you run threw all the code sections and apply the neural on a MWBC not counting, or that one conductor in a 3way is always off, you can always run 4 NMs together.
ptonsparky
Tom
- Occupation
- EC - retired
- Occupation
- Licensed Electrician
- Location
- New Jersey
- Occupation
- Journeyman Electrician
In many cases 4-3 wire cables (H-H-N), 12 conductors (not counting EGC's) would still only count as 8 CCC's.
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
The catch with that method is that you can only do it ten times and then typing becomes a real chore. Not to mention the mess and the inevitable complaints from homeowners. I would substitute pieces of lath or something.
- Status