Wireway or axzilary gutter

[Scott Smith Walker]

How do I size a wire way that will be utilized to feed seven 100A sub panels in an electrical room with the distribution panel in the same room. I have limited overhead ceiling space and think a wire way will look better in the end.

The wire way will run under the panels four on one wall and three on an adjoining wall. Each panel will have one 1 1/4" conduit out of the bottom and into the top of the wire way. Conductors will pull strait through to the distribution panel with no splices and I will have less than 30 current carrying conductors in it.

Is this considered a wire way or an auxiliary gutter.

My initial thought would be 6x1.5+1.5+1.5+1.5=13.5" tall. But this seams to large.

 

[augie47]

Regardless of it's classification as a wireway or auxiliary gutter, you are allows 20% of the interior cross section area.
a 4 x 4 wireway would allow a fill of 3.2 in which would allow 33 #3s. At first look that seems it would suffice for your needs.

 

[Dennis Alwon]

An auxiliary gutter is used for service equipment-- I believe-- and has a hinged cover. A metal wireway may have either a hinged cover or removeable cover. It seems like you have a metal wireway

 

[Dennis Alwon]

376.23(B) talks about wireways used as a pull box. If this is what you have then sizing is done using314.28(A)(1) is used for straight pulls and 314.28(A)(2) is for angle pulls

 

[jim dungar]

An auxiliary gutter is used for service equipment-- I believe-- and has a hinged cover. A metal wireway may have either a hinged cover or removeable cover. It seems like you have a metal wireway

Simple analogies.
An aux gutter adds to the amount of space in a piece of equipment. A wireway runs between pieces of equipment.

 

[Dennis Alwon]

Simple analogies.
An aux gutter adds to the amount of space in a piece of equipment. A wireway runs between pieces of equipment.

How does it do that. Physically what is the difference between the two?

 

[Dennis Alwon]

I found this that says they are basically the same except for the listing. I got it from here

Since Article 366 Auxiliary Gutters, Article 376 Metal Wireways, and 378 Nonmetallic Wireways are very similar, we will discuss them as a group. They are listed to UL Standard 870. All of these items serve as an enclosure for conductors, they look the same and perform essentially the same function; the difference is how they are marked and identified. If the label on one of these products states Gutter, then it must be used in accordance with Article 366. The unique feature of a gutter is found in 366.2, where we find the definition of a gutter. It states that it is to be used as a supplemental wiring space for other equipment. So, from this language, we know that if an enclosure is listed as a gutter, then it must be installed in combination with meter centers, distribution centers, switchboards, etc.; it can?t be used as a stand-alone wireway or raceway.

 

[jim dungar]

I found this that says they are basically the same except for the listing. I got it from here

Notice this in your quote "... It states that it [a gutter] is to be used as a supplemental wiring space....it can?t be used as a stand-alone wireway or raceway."

It is kind of like being a UL Listed stand alone item, or a UL Recognized component, that must be used with something else.