Wire bundling

[ironphill]

I've never actually gotten tagged on this from a city inspector, but private inspectors site it on existing houses all the time. When all the romex comes into a panel through a single 2 1/2" hole, they call it bundling and then tell the home owner that you can't do that. They've also said it needs romex connectors instead of pop in bushings, but that's beside the point. I've look the code up and down, and the only thing I can find about bundling (that's relevant) is that if you do it for more than 24", you have to derate the wire. So regardless of whether it's "bundled" coming into the panel, it's only "bundled" for a half inch tops. Where in the codebook does it say you can't do that? On a side note, the city inspectors won't let you use mc cable... at all,... anywhere. You have to sleeve you're own stranded with flex. Anybody ever heard of that?

 

[tryinghard]

Your right about the bundling 310.15(B)(2) but I believe the connector specifies up to 2 cables each.

 

[jimport]

Have you asked what their objection is to the MC cable?

 

[raider1]

Check out section 334.80 in the 2005 NEC. The last paragraph of that section states:

"Where more than two NM cables containing two or more current-carrying conductors are bundled together and pass through wood framing that is to be fire- or draft-stopped using thermal insulation or sealing foam, the allowable ampacity of each conductor shall be adjusted in accordance with Table 310.15(B)(2)(a)."

Also the 2008 NEC clarifys that the exception to 310.15(A)(2) does not apply to this section.

So if you run more than 2 NM cable through wood framing that is to be draft stoped you must derate them in accordance with 310.15(B)(2)(a).

As for not allowing you to use MC cable what is their justification?

Chris

 

[don_resqcapt19]

It may not be bundling, but it is a code violation. You can't bring multiple NMs through a single 2.5" hole. Take a look at 312.5(C). There is one exception, but it is very restrictive.

 

[220/221]

You can't bring multiple NMs through a single 2.5" hole. Take a look at 312.5(C). There is one exception, but it is very restrictive.

You can't LEGALLY do it.

I miilion homes in my home town are done that way :roll:

I have changed out a LOT of services in my time and haven't seen one single issue from this type of installation. I have however seen COUNTLESS failures at connectors which tend to damage the sheath by pinching it.

This is a case of the code being flat out wrong.

BTW, I am talking about exterior service panels with the cables run thru the back, into the wall.

 

[don_resqcapt19]

You can't LEGALLY do it.

I miilion homes in my home town are done that way :roll:

I have changed out a LOT of services in my time and haven't seen one single issue from this type of installation. I have however seen COUNTLESS failures at connectors which tend to damage the sheath by pinching it.

This is a case of the code being flat out wrong.

BTW, I am talking about exterior service panels with the cables run thru the back, into the wall.

You do it here and you get to come back and change it becuase you will get a red tag. As far as damage at connectors that comes from either unqualified installers or a qualified installer that was not paying attention to his work.

 

[charlie b]

It may not be bundling, but it is a code violation. You can't bring multiple NMs through a single 2.5" hole. Take a look at 312.5(C).

I am not sure I understand this one. First of all, it is not clear to me that a panelboard is included in the scope of 312. I read the definition of "cabinet' in article 100, but I am still not sure.

Secondly, I don't think 312.5(C) says you can't have more than one cable in a conduit that connects to a cabinet. It says that each cable entering the cabinet must be secured to the cabinet. So it seems to me that anything you do that would secure one cable can also be used to secure two or more cables.

 

[220/221]

You do it here and you get to come back and change it becuase you will get a red tag.

How do you enter the back of a panel thru the wall with 20 cables?

As far as damage at connectors that comes from either unqualified installers or a qualified installer that was not paying attention to his work

That is debatable. Like I said, I have done a LOT of remodel/rework over the years and the romex at the connector is commonly a vulnerable spot just like the old BX at connectors. The wire inside the cable is in good shape but right at the connector it somehow shows signs of damage. Just an observation.

Typical install here: I'm not seeing how (or WHY) to get those cables into individual connectors.

I know we are talking about romex but here is typical damage to BX at the connector.

 

[C3PO]

I am not sure I understand this one. First of all, it is not clear to me that a panelboard is included in the scope of 312. I read the definition of "cabinet' in article 100, but I am still not sure.

[SIZE=3 [/SIZE]

Charlie the definition of panelboard says that it is designed to be placed in a cabinet or cutout box so wouldn't 312.5 apply to this?

 

[charlie b]

Charlie the definition of panelboard says that it is designed to be placed in a cabinet or cutout box so wouldn't 312.5 apply to this?

OK. I'll buy that.

 

[acrwc10]

How do you enter the back of a panel thru the wall with 20 cables?




That is debatable. Like I said, I have done a LOT of remodel/rework over the years and the romex at the connector is commonly a vulnerable spot just like the old BX at connectors. The wire inside the cable is in good shape but right at the connector it somehow shows signs of damage. Just an observation.

Typical install here: I'm not seeing how (or WHY) to get those cables into individual connectors.

I see two violations 1) to many cables through one fitting 2) you have an exterior box ( weather tight ) that you have cut a hole in above the live parts, There is a reason the factory doesn't put K.O's above the bussing.

 

[peter d]

you have an exterior box ( weather tight ) that you have cut a hole in above the live parts, There is a reason the factory doesn't put K.O's above the bussing.

It's under an overhang, and it's in Phoenix. I don't see the issue.

 

[acrwc10]

It's under an overhang, and it's in Phoenix. I don't see the issue.

So let me see if I understand what you are saying "it doesn't rain in Phoenix"?????????????? that over hang does not make that panel in a dry location. Wind and rain happen in Phoenix, or so I've heard. :grin:

 

[480sparky]

It's under an overhang, and it's in Phoenix. I don't see the issue.

So what if the overhang is three stories up?

 

[don_resqcapt19]

Charlie,
The only device that I am aware of that is suitable for securing the NM cables is a NM connector. There are none that are suitable for more than 3 cables.

 

[peter d]

So what if the overhang is three stories up?

In this particular installation, I don't see the problem with what 220 did. I didn't say it would be acceptable in all circumstances.

Although 220 will tell you that just about every outdoor panel is done in Arizona that way, and many of them are not protected by overhangs either.

 

[220/221]

So what if the overhang is three stories up?

That's why the make caulk!


Don't worry. I put drip loops on all the conductors

 

[acrwc10]

In this particular installation, I don't see the problem with what 220 did. I didn't say it would be acceptable in all circumstances.

Although 220 will tell you that just about every outdoor panel is done in Arizona that way, and many of them are not protected by overhangs either.

I don't want to offend you but, that is the most over used excuse in the book for installing with code violations.

 

[benaround]

Charlie,
The only device that I am aware of that is suitable for securing the NM cables is a NM connector. There are none that are suitable for more than 3 cables.

Don, Bob (iwire) got me on this one a few weeks back 334.30, example: 2"

PVC conduit with nm cables giong to a panel.