I`m changing out a older service panel. I`m planning on installing a outdoor 200amp panel and droping from the bottom of the panel with 2- 2"LB`s for the wiring they will go through the brick work under the house at that point the pipe will be cut off and the wiring going to there circuits.Didn`t I read somewhere the wires must be connected to the box and this wasn`t allowed anymore? If this is the case someone please steer me in the right direction.Also where do I find the conduit fill for a sheathed cable vs regular fill?

This is a very very old house the inside walls aren`t 3 1/2 " deep or I`d be putting the panel indide they laid 2x4`s side ways and has boards on both sides.

With "fill" you are going to add up fast. You use the dimension of the cable as it's widest point as a diameter, then compute based on a circle that size. A 12/2 Romex "fills" about the same as a #1 or #2 THHN (9-13 in a 2" PVC)
The other problem is derating. Once you get over 4 Romex in that pipe you will start eating up your ampacity, beyond the hit from 240.4(D)

Check out Chapter 9, Table 1, Notes to Tables (9), on page 617, for conduit fill.
Check out 300.15(C) for sleeving.
334.30 requires NM to be stapled within 12 inches of every cabinet, box or fitting.

I asked for clarification from Jeff Sargent of NFPA at a seminar earlier this year. He stated we should either install a cable clamp at the end of the conduit, or to bush the end and extend the sheathing at least 1/4 inch into the enclosure (box). If we choose the bushed option, the staples need to be within 8 inches of the end of the conduit.

Would this be like a nipple as far as the fill? I really shouldn`t have lots of circuits but we all know how that goes. The LB`s will come directly out of the panel just enough pipe to glue the male adapter then the bricks are only brick thick not block veneered as new homes and the pipe will extend only 10" or so.

Thanks for the advice and artical numbers.Sometimes when you`re working its hard to take time to actually sit and read or find all the code issues.I really see where the continueing ed is important.

First I would attempt to install the panel interior, the outdoor enclosure has to be more expensive.

Second I assume you are routing the cables to the circuits once your in the building, rather than terminate the two sleeves at the old panel inside.

Third I would look at 312.5 (c) but that permissive language only applies to cables at the top of the panel

[This message has been edited by cpal (edited 07-27-2004).]

If you can establish it is less than 24" this is a nipple (65% fill, no derating).
Can you LB through the wall and directly into a gutter? Then you could punch holes and use Romex connectors from there.

Thats it 312.5c thats what has me worried? Now does this mean I can`t wire this the way I planned?Maybe I`ll see the AJH if possible before we start.It`s out of town so I don`t really know them at all.Matter of fact the home owner was picking up and paid for all the permits.The old panel is a mess and is In the kitchen cabinet it has 3 fuses and 1 220 pull out set whitch is wired to stove, h2o heater, and a a/c unit I wander why the 30 amp fuses keep blowing the guy ask.....I`m looking at 312.5c Man I see no way around it. Unless I turn the panel upside down and then I`ll be coming out of the top with the pipe....Just kidding.I really wish this could be changed.

If I were you I'd run!!!!

I still do not understand how you intend to pick up the existing branch circuits from the new loadcenter.

I also agree that what is good for the top of the panel should be good for the bottom, side, and back etc.

But I also agree that the language as written is not in your favor.

Realistically what you propose doing has been done for a long time without a history of failure.But that does not make a Code compliant installation. That permissive exception appeared in the 1999 NEC.

If you intend to use the existing load center as a junction box and if the enclosure satisfies the requirements of 314.16 thru 314.28 etc. then I would strongly consider a complete raceway (ridged or flexible) to the old load center and forget the cables.

I'll check later to see if you re-post

charlie p

No Sir I`m planning on totally rewiring the house everything must go including the existing load center and all branch circuits.I`ve put a call in to the Inspector but haven`t heard from him/Her. My co-worker says we should change the service wire the existing load center to 60 amp breaker in panel out side and once inspection complete go back and rewire the house as planned But thats not the proper thing to do.But I must admit its a thought.I`m hoping the inspector will come through can`t they make a waver or is this in ya`lls opinion something they wouldn`t let me do because of code rules.

You mentioned that you can't fit a flush panel inside because of the flat studs. Can you put a surface mounted board in there, or even inset a surface board partway between the studs? Then you wouldn't have to deal with trying to run everything though LBs.

There are panels available that are meant to have wire access on the inside of the structure with the breakers on the outside.

Alternatively you could nipple into a J Box in the crawl space, install barrier strips in the J box, and run your cable from there. Using the barrier strips makes it a neater job and avoids the rat's nest effect of using wire nuts.
--
Tom Horne

312.5(C) Exception(a)- says you can fasten the NM cable within 12 inches of the raceway.

Installations that are installed 'after' the inspection, so you can pass an inspection are in my opinion a crime, especially when you are aware of the violation.

Pierre

Reel-Break ---

The NEC does not address all issues. In particular, since NM cables are not usually run in conduit and then into boxes, the code is silent on correct methods of fastening cables in your instance.

I often run 4 6-3 subpanel cables into main panels. I put a 2-1/2" piece of conduit into the main. Then I run the 6-3s and whatever other large cables I have into the 3" conduit and on into the main panel. The cables are fastened together outside of the conduit with zip ties.

This is sufficient to meet the intent of the code: to protect the NM cable outside of a box by ensuring that the sheath terminates inside of a box.

Hey someone better read all of 312.5c it says in the exceptions that nm sheathed cables must meet all the following conditions a-g....and b states that the raceway extends above the encloseure..So I called NC state board and they contend that no way can you have a race way under a panel with the wires not secured to the cabinet,meter socket or cutout box.George I don`t see how it passes 312.5c I hate it but I have had to change my wiring practices.It makes no sense to me.

Reel-Break ---

The NEC does not address all issues.

Referring to the ICC electrical section:

"Maximum support distance from box" is the term used. Staples are not needed.

Work out something with your AHJ.

Reel-Break...I would have to agree with cpal and install the panel in the dwelling.If your rewiring the house then redesign the location of the panel in the building somewhere...maybe relocate the service to another side of the house or put the main in the meter outside and put a sub-panel IN the house somewhere...maybe in the utility room with the heating equipment.Also staples are not the only way to support romex.See 334.30 commentary in the hardback says that wires installed through bored holes are considered supported.

Yea I tried to work out something but he wouldn`t budge.So I changed the service put a 200a meter main outside left the old stuff in the kitchen cabinet and pulled the 240 loads out side ran a wire for the micro wave and added couple small appliance circuits so it kinda worked out.But the ajh maintains that 312.5c You cannot place a raceway under a panel and run NM cables and not have them secured to the box. So to do this you`d have to place a troff or big JB under house fasten all cables to it then you could run up to panel.But he say`s in no way can you stub up under a panel run nm cables and just staple them 12" from pipe openning.HE agrees it makes no sense to him but he has to uphold the law of the land. OK guess it`s time to move on Thanks for the feed back everyone.