Long Simmering Box Fill Question - Opinions wanted?

[jwelectric]

Re: Long Simmering Box Fill Question - Opinions wanted?

When a device box for a receptacle is roughed in with two many wires the inspector will turn it down on rough not wait until the receptacle is installed. Do we expect the inspector to make notes of every box in a house?

In the area that I live in the inspector will turn them down even if there was no wire in them. Should you want to use a 3 ? inch pancake box you best be mounting a door chime.

314.16 (A)
(A) Box Volume Calculations. The volume of a wiring enclosure (box) shall be the total volume of the assembled sections and, where used, the space provided by plaster rings, domed covers, extension rings, and so forth, that are marked with their volume or are made from boxes the dimensions of which are listed in Table 314.16(A).

I have always thought that the canopy is part of the light fixture and plays no role with the box.
The canopy is designed for the joints that the fixture will contain at the box.

 

[jwelectric]

Re: Long Simmering Box Fill Question - Opinions wanted?

As to this exception that has been brought up;
314.16 (B) (1)
Exception: An equipment grounding conductor or conductors or not over four fixture wires smaller than 14 AWG, or both, shall be permitted to be omitted from the calculations where they enter a box from a domed luminaire (fixture) or similar canopy and terminate within that box.

This exception states that no more than 4 conductors and they must be smaller that 14 and have to come from the fixture. This is the purpose of the canopy is to cover these wires.

A ceiling fan is NOT a light fixture.
422.18 Support of Ceiling-Suspended (Paddle) Fans.
Ceiling-suspended (paddle) fans shall be supported independently of an outlet box or by listed outlet box or outlet box systems identified for the use and installed in accordance with 314.27(D).

A ceiling fan is an appliance.

 

[George Stolz]

Re: Long Simmering Box Fill Question - Opinions wanted?

Originally posted by curt swartz:
George, I?m not saying that the canopy can?t be included but it must be marked with its volume by the manufacture.

Now you're adding words. It doesn't say the manufacturer does the marking, it just says "marked." If you do the work yourself you can mark the canopy yourself, for the code, inspector, and future electricians curious about how big the canopy is.

Most electrical inspectors in my area will not accept 3/0 pancakes since the marked volume is not enough for even a single 14-2 NM cable.

So will they not accept gutter boxes either, if their volume is not marked from the factory?

JW wrote:
I have always thought that the canopy is part of the light fixture and plays no role with the box.

Once it was believed that the world was flat and monsters that swallowed ships whole swam at the edges.

 

[jwelectric]

Re: Long Simmering Box Fill Question - Opinions wanted?

(2) Other Boxes. Boxes 1650 cm3 (100 in.3) or less, other than those described in Table 314.16(A), and nonmetallic boxes shall be durably and legibly marked by the manufacturer with their volume. Boxes described in Table 314.16(A) that have a volume larger than is designated in the table shall be permitted to have their volume marked as required by this section.

 

[infinity]

Re: Long Simmering Box Fill Question - Opinions wanted?

I don't see how you could fail a rough-in inspection when the final installation uses the exception to 314.16(B)(1). The inspector would have to check after the fixture were installed to see if you complied with the exception.

 

[jwelectric]

Re: Long Simmering Box Fill Question - Opinions wanted?

Originally posted by infinity:
I don't see how you could fail a rough-in inspection when the final installation uses the exception to 314.16(B)(1). The inspector would have to check after the fixture were installed to see if you complied with the exception.

Exception: An equipment grounding conductor or conductors or not over four fixture wires smaller than 14 AWG, or both, shall be permitted to be omitted from the calculations where they enter a box from a domed luminaire (fixture) or similar canopy and terminate within that box.

How would this exception have any bearing on the box fill calculation?
It clearly states that four FIXTURE wires shall be omitted if the come from the fixture and terminate in the box.

There is no relief for the conductors that the electrician installs in the box.

 

[iwire]

Re: Long Simmering Box Fill Question - Opinions wanted?

Originally posted by jwelectric:
There is no relief for the conductors that the electrician installs in the box.

Sure there is, if the canopy is marked with the volume as directly allowed by 314.16(A).

Scott's post is IMO directly on point as far as failing the rough.

With your logic the job would not pass anyway because all of the boxes are not covered. I don't see why the wording to allow the fixture canopy to count in box fill calcs is even there if you are not allowed to use it.

By the way, I do not recall seeing a canopy marked with it's volume.

 

[busman]

Re: Long Simmering Box Fill Question - Opinions wanted?

I did a google search on pancake box fill and found out that Mike Holt has addressed this issue:

Mike Holt Box Sizing Article

Mark

 

[jwelectric]

Re: Long Simmering Box Fill Question - Opinions wanted?

Originally posted by electricmanscott:
I don't see why the wording to allow the fixture canopy to count in box fill calcs is even there if you are not allowed to use it.

If you don't mind please show me where the code allows the canopy to be included in the box fill calculation.

 

[iwire]

Re: Long Simmering Box Fill Question - Opinions wanted?

Originally posted by jwelectric:
If you don't mind please show me where the code allows the canopy to be included in the box fill calculation.

Right here in 314.16(A)

314.16 Number of Conductors in Outlet, Device, and Junction Boxes, and Conduit Bodies.
Boxes and conduit bodies shall be of sufficient size to provide free space for all enclosed conductors. In no case shall the volume of the box, as calculated in 314.16(A), be less than the fill calculation as calculated in 314.16(B). The minimum volume for conduit bodies shall be as calculated in 314.16(C).

The provisions of this section shall not apply to terminal housings supplied with motors.

FPN:For volume requirements of motor terminal housings, see 430.12.
Boxes and conduit bodies enclosing conductors 4 AWG or larger shall also comply with the provisions of 314.28.


(A) Box Volume Calculations. The volume of a wiring enclosure (box) shall be the total volume of the assembled sections, and, where used, the space provided by plaster rings, domed covers, extension rings, and so forth, that are marked with their volume or are made from boxes the dimensions of which are listed in Table 314.16(A).

IMO a canopy could be 'so forth' if marked with it's volume but that is a call better left to the AHJ than us here.

That is unless you have an NEC definition of "so forth".

We can count a domed cover even though it would not be in place during the rough inspection.

 

[busman]

Re: Long Simmering Box Fill Question - Opinions wanted?

I thought in this case "domed cover" was referring to an RS cover.

Mark

 

[jwelectric]

Re: Long Simmering Box Fill Question - Opinions wanted?

I agree with what you have posted but not with the explanation.

At the point in time that I have roughed in the box and my box fill exceeds that marked on that box I am in violation of the NEC.

In order for me to comply with the box fill requirements at the rough-in stage the canopy would be required to be installed at that time.

To base the statement on, ?well I am going to put a dome cover on this box that is listed and marked with the Cu. In.?, would require an assumption on the part of the inspector. This is not allowed when it is clear that this box is over filled at the time of rough-in.

 

[iwire]

Re: Long Simmering Box Fill Question - Opinions wanted?

Originally posted by jwelectric:
At the point in time that I have roughed in the box and my box fill exceeds that marked on that box I am in violation of the NEC.

Thats hogwash

Originally posted by jwelectric:
To base the statement on, ?well I am going to put a dome cover on this box that is listed and marked with the Cu. In.?, would require an assumption on the part of the inspector. This is not allowed when it is clear that this box is over filled at the time of rough-in.

An inspector has to make a lot of assumptions, like that box in the ceiling will indeed become a lighting outlet not a smoke detector etc.

I am required to provide GFCI protected receptacle outlet in the bathroom, if it's not there during rough will you fail me?

 

[electricmanscott]

Re: Long Simmering Box Fill Question - Opinions wanted?

I'll thank Bob for backing up my point better than I could have. This is one of those times (and there are many) that common sense in applying the code would be of more use than trying to interpret every nuance word by word. What I mean in plain english is we all know that the canopy of the light will most times provide more than adequate space for the wiring and there is no hazard that will be present.

[ August 08, 2005, 09:56 AM: Message edited by: electricmanscott ]

 

[busman]

Re: Long Simmering Box Fill Question - Opinions wanted?

How did we conclude that domed covers and canopies are the same thing. Article 314 talks about domed covers and Article 410 canopies. I don't think they are the same thing.

Respectfully,

Mark

 

[electricmanscott]

Re: Long Simmering Box Fill Question - Opinions wanted?

Mark I would say that the canopy can be legitimately classified under the " and so forth" wording. Looking for the NEC definition of that right now. :roll:

 

[jwelectric]

Re: Long Simmering Box Fill Question - Opinions wanted?

Thats hogwash , at that point it is no more a violation than the cover being missing. A rough inspection is not a final inspection.

So then when an inspector fails a rough-in then all I have to say is this is not the final and I am not finished.
Come on Bob we both know better than this type of thinking.

If the box is over filled at the rough-in then at this point in time it is in violation no matter what. If I don?t want it to be in violation at time of rough then add an extension.

There is also the point that there is no canopy that I have ever seen that has the cu. in. marked on it by the manufacture.


[ August 08, 2005, 10:32 AM: Message edited by: jwelectric ]

 

[jwelectric]

Re: Long Simmering Box Fill Question - Opinions wanted?

Originally posted by iwire:

By the way, I do not recall seeing a canopy marked with it's volume.

 

[marinesgt0411]

Re: Long Simmering Box Fill Question - Opinions wanted?

Originally posted by busman:
George,

I mentioned the question about lighting fixtures because that is the first words in the title of article 410 "Lighting Fixtures, Lampholders, Lamps, and Receptacles". Probably should use luminaire.

I started thinking about this because I have a job to install a ceiling fan in a business with a drop ceiling with wooden framing about 2 feet above the ceiling. I began with the best solution being a 2x8 attached to the framing with a fan box at the bottom. I went looking for a saddle type fan box (it has to be metal since the existing method is MC cable). The only metal box I could find with a suitable bracket (one that would attach to the bottom of the 2x8 was a pancake box. Hence the question. Any better ideas? I do much more residential than commercial so I don't do many drop ceilings.

Thanks,

Mark

I have solved this problem two differant ways

1) install the fan box up in the rafters and change the down rod to the length needed just drill a hole in the cieling tile and pass the down rod through. canopy and box above above ceiling tile.

2) mount fan box on T-bar bracket (Caddy makes them) clipped to cieling grid, run 3/8 all thread from box to support in rafters or red iron, mount fan to fan box. conopy is against cieling tile