Field made conduit entry into load center

wwhitney said:
I though the listing doesn't include the enclosure and just covers the guts.

Cheers, Wayne
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For a one piece panelboard (loadcenter) I think you could have different UL listings for different components. Although the cabinet isnt required to be listed per the NEC, usually they are. Unless the product standard for panel boards has a provision to list the cabinet with the guts as an assembly?
 
A UL Listing is about how a device was built by the factory. The stuff we do in the field, such as punching holes, is a modification to a Listed device. UL says it is up to the AHJ to decide if a field modification results in a situation that renders the device unsuitable.
UL says it can provide guidance to the AHJ if requested, like the letter mentioned by jraef.
 
electrofelon said:
For a one piece panelboard (loadcenter) I think you could have different UL listings for different components.
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I took a look at UL 67 on Panelboards. The standard defines panelboard the same as the NEC (almost, it appends "or placed in an enclosure" to the NEC definition), the term excludes the enclosure. The term "panelboard interior" is offered as a synonym. An "enclosed panelboard" is a panelboard plus its enclosure (actually its definition repeats part of the "panelboard" definition and then appends "installed in a suitable cabinet, cutout box, or enclosure suitable for a panelboard application.")

UL 67 7.1.1 says "A panelboard shall be constructed for use in a switchboard, cabinet or cutout box. An enclosed panelboard shall be provided with an enclosure complying with" UL 50. I didn't read all of UL 67, but the standard has a few other requirements for enclosed panelboards, such as when gutter space is required and how large it needs to be. I didn't see anything saying that the panelboard portion of an enclosed panelboard must be used in the provided enclosure.

So I believe that it's true that the panelboard's listing does not depend on the enclosure that it is usually provided with it. You can swap out the enclosure, although there are certainly clearances you are required to maintain.

Cheers, Wayne

P.S. As an aside, I was interested to note that UL 67 11.3.2 provides a way to compute the ampacity of panelboard rated for up to 400A aluminum busbars, 1600A for copper busbars, and forego the UL 67 Section 21 Temperature Test. It specifies an allowable current density of 1000A/in^2 for solid copper, 750A/in^2 for solid aluminum of specified minimum conductivity, and 200A/in^2 at bolted connections, with some exceptions.
 
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jim dungar said:
A UL Listing is about how a device was built by the factory. The stuff we do in the field, such as punching holes, is a modification to a Listed device. UL says it is up to the AHJ to decide if a field modification results in a situation that renders the device unsuitable.
UL says it can provide guidance to the AHJ if requested, like the letter mentioned by jraef.
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Right, and perhaps its a nitpick and a pet peeve, but there is no such thing as a "listing violation". There is 110.2 per the NEC. If you specifically do something contrary to the instructions, that is 110.3.
 
wwhitney said:
It specifies an allowable current density of 1000A/in^2 for solid copper, 750A/in^2 for solid aluminum of specified minimum conductivity, and 200A/in^2 at bolted connections, with some exceptions.
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I don't know of any major manufacturer that has used this method for commercially available panelboards since the early 60's. It uses more bus material, so now it is primarily only used by specialty manufacturers and one-off products.
 
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voltairzap said:
The field cut overlaps the factory KOs. The factory KOs are always the wrong size and in the wrong place.
I understand his concern with the locknuts might not seat against the lower side of the can.
Both locknuts are hard tightened.
there is a hub on one end of the nipple and a grounding bushing on the other with a ground wire connecting both enclosures.
We contacted General Electric (now ABB). They only have approval for the factory KOs, with no mention of field penetrations.
His suggestion is a UL approved third party inspection.
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Can you post a photo of the install?
 
Depending on what you have done the issue may not be the fact you made a hole rather where and for what and done correctly.

I found this on eatons web site. It supports the fact you can make your own hole etc.
What is important is, as long as it does not violate another part of the NEC.


So a picture would defently help. As far as the adding a hole, yes.

Send him the link and see if it helps.

On the flip side I googled can you do it and AI said it's a violation. Maybe he goggled it?

Wish you the best of luck.

Try a cup of coffee with a donut and have a conversation educating this insp. Discussion point would be the hole. How made and the effect area. Then location of the hole related to other parts of the code. Like bending space for feeder or service conductors within the gutter portion of the load center etc. This might help come to a mutual understanding of what is and is not allowed. Bring you book have sections marked as key point. Don't forget the workman like manner as it's usually a fall back from the inspector.
Happy Thanksgiving
 

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Edit. Add this link as an example.

Table 312.6(A) Minimum Wire-Bending Space at Terminals and Minimum Width of Wiring Gutters.

If this panel was fed with 1 AWG aluminum conductors, 2 inches of wire bending space would be required for deflection.
www.electricallicenserenewal.com

Here is another one paying attention to X.

408.55(C) Back Wire-Bending Space.

Use NEC Tables 312.6(A) or 312.6(B) to determine minimum dimensions when raceways and cables enter the back of a panelboard enclosure. On a different note: Based on the wiring configuration of the panelboard, is this a service or a subpanel?
www.electricallicenserenewal.com

These are just examples for conversation be sure you discussion applies to your code year.
 
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Only times I've seen or experienced an issue with field made openings, would be with a NEMA 3 or higher in certain locations on panel or if the field cut opening transected other factory KO's. The later I seen the KO's failing and having inadequate support for the conduit or connector. This was where the contractor indicated the pipe didn't line up with the factory KO's. where they wanted it so they cut a new one that transected 2 large factory KO's and the KO's began separating and breaking out.
Another I saw where someone field cut too close to an edge and it compromised the enclosure integrity, welded seam failed. Another too close to back wall and couldn't get a locknut onto the connector.
 
Here is an example how a field cut could be a violation

I received this picture a while back and ask my option.

It's applicable in way of bending space at terminals.

Lot more going on so ignore the rest.

You can also see the lug twisted as result.
 

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