Wireway conduit penetrations

[cdennison]

The town electrical inspector rejected a high voltage pre-fab electrical equipment enclosure which has a wireway around the top interior of the enclosure picking up lights, smoke heads and receptacles, because the conduits from the ceiling mounted components entered the wireway through cutouts in the top part of the bolt-on wireway cover (it is against the ceiling and has the cover facing horizontally). The cover could be removed with the conduits being attached to an extension of the wireway enclosure.

We complained that the conduits were held in place firmly but the inspector said that the conduits could only enter the wireway through the provided knockouts at the bottom of the wireway and not through the cutouts at the top of the horizontal cover. This would mean we would have to take the conduits down in front of the wireway covers and bring them up into the bottom of the wireway.

I can find nothing in the NEC code that addresses the entrance of conduits into wireways. Am I missing something? Thanks

[Jerry Peck - Codeman]

I can think of several reasons the inspector turned that down.

For example:
- The raceways are required to be installed completely before the conductors are run in the conduits, and from your description I am envisioning that the conduits are mounted to the removable cover. You would need to clarify this.
- With the raceways mounted to, or cut through and not mounted to, the removable cover, the raceways would not be properly terminated.
- The conduits would restrict the proper removal of the cover.

I will e-mail my NEC Codeman to make sure he sees your question and have him reply too.

In the meantime, do you have a photo, drawing, or additional descriptions you could provide?

Thank you,

[Jerry Peck - Codeman]

I've re-read your question a few times and I keep coming up with these questions:

high voltage pre-fab electrical equipment enclosure which has a wireway around the top interior of the enclosure

The wireway is running "around the top of the interior of the enclosure", indicating that the wireway is inside, and part of, the listed and labeled equipment.

the conduits from the ceiling mounted components entered the wireway through cutouts in the top part of the bolt-on wireway cover (it is against the ceiling and has the cover facing horizontally).

There is a cover over the built-in wireway which faces up, i.e., serves as part of the top of the equipment, and that cover is screwed on to the listed equipment, with the conduits running vertically down through cut outs in the cover.

The cover could be removed with the conduits being attached to an extension of the wireway enclosure.

This part I am not sure of. The conduits are, or are not, running vertically down through the cover? You are saying that you notched the cover around the conduits? I'm not envisioning what you are describing in this part.

I can find nothing in the NEC code that addresses the entrance of conduits into wireways.

This is what I am referring to regarding installing the conduits in complete runs. (underlining and bold are mine)
- From the 2008 NEC.
- - 300.18 Raceway Installations.
- - - (A) Complete Runs. Raceways, other than busways or exposed raceways having hinged or removable covers, shall be installed complete between outlet, junction, or splicing points prior to the installation of conductors. Where required to facilitate the installation of utilization equipment, the raceway shall be permitted to be initially installed without a terminating connection at the equipment. Prewired raceway assemblies shall be permitted only where specifically permitted in this Code for the applicable wiring method.
- - - - Exception: Short sections of raceways used to contain conductors or cable assemblies for protection from physical damage shall not be required to be installed complete between outlet, junction, or splicing points.
- - - (B) Welding. Metal raceways shall not be supported, terminated, or connected by welding to the raceway unless specifically designed to be or otherwise specifically permitted to be in this Code.

Then, being as you are entering the wireway from the top where the access cover is and not the bottom where intended, in addition to the question regarding the conduits entering through the removable cover are these questions: Do you still have the required wire bending space? Are the conduits properly terminated in proper fittings? Are the conduits properly secured and supported at the termination points?

[Jerry Peck - Codeman]

Attaching photos e-mailed to me.

The pictures show the cutouts on the wireway cover where the conduits were brought in and attached. The conduits ends were attached to the wireway where the body is bent around (see attached picture with the cover off) or an additional steel piece is added so that the conduit can be attached.

wireway penetrations_resize.jpg

Wireway 2_resize.JPG

[Jerry Peck - Codeman]

Thank you for the photos, that is not at all what I was envisioning.

Also, being as you stated the wireway was running around the top of high-voltage prefab equipment, that would indicate the equipment is operating at 600 volts or more.
- ARTICLE 490 Equipment, Over 600 Volts, Nominal
- - 490.2 Definition.
- - - High Voltage. For the purposes of this article, more than 600 volts, nominal.

I have e-mailed my NEC Codeman for his input, he was waiting for photos or additional description of the installation.

In the mean time, though, yes, notching the cover as shown has a detrimental effect on the original and intended design and use of the cover, which is to provide a complete enclosure for the contents within the wireway.
- III. Construction Specifications
- - 376.100 Construction.
- - - (A) Electrical and Mechanical Continuity. Wireways shall be constructed and installed so that adequate electrical and mechanical continuity of the complete system is secured.
- - - (B) Substantial Construction. Wireways shall be of substantial construction and shall provide a complete enclosure for the contained conductors. All surfaces, both interior and exterior, shall be suitably protected from corrosion. Corner joints shall be made tight, and where the assembly is held together by rivets, bolts, or screws, such fasteners shall be spaced not more than 300 mm (12 in.) apart.
- - - (C) Smooth Rounded Edges. Suitable bushings, shields, or fittings having smooth, rounded edges shall be provided where conductors pass between wireways, through partitions, around bends, between wireways and cabinets or junction boxes, and at other locations where necessary to prevent abrasion of the insulation of the conductors.
- - - (D) Covers. Covers shall be securely fastened to the wireway.

I also have concerns regarding the wireway which is shown as being notched out on the back, presumably for a structural support which creates a through-penetration - the second photo, is that a structural item which penetrates through the wireway?

If so, the manufacturer of the wireway would need to provide an approved drawing showing the proper and approved method of repairing the wireway so the enclosure created by the wireway is keep intact and separate from the structural item which runs through it. First, one would not want to energize that item, secondly, one would want to contain any fire within the wireway to remain within the wireway.

My NEC Codeman should be able to add additional comments and information.

[Joe Tedesco]

The UL Standard for Safety for Wireways, Auxiliary Gutters, and Associated Fittings, UL 870 Eighth Edition, Dated June 6, 2008 and Section 110.3(B) in the 2008 NEC support the interpretations given here and the citation.

We cannot agree with this installation. Please contact a UL Engineer for any further assistance. See UL (place mouse over cursor, right click, select 'Open in New Window', then click - http://www.ul.com )