Code Compliant Cable Tray?

[roger]

And again, if the part has been field modified to the extent where the label is completely incorrect (ie claiming .20 square inches cross section when only .10 remains) you believe that's okay?

If the manufacturer knows and feels this to be an issue it should be included in the instructions so, I would say yes, it's OK. If the manufacturer does not see it being an issue, the instructions would be all that is needed for approval.

Roger

 

[CAM]

If the manufacturer knows and feels this to be an issue it should be included in the instructions so, I would say yes, it's OK. If the manufacturer does not see it being an issue, the instructions would be all that is needed for approval.

Roger

So in your view if the manufacturer says "do it" then it's okay. A foreign manufacturer can come here with product designed for foreign regulations, simply claim it meets NEC requirements, and everything is great? Because that is exactly what happened with wire mesh basket tray. The French brought it here without making a single change or concession to the NEC. UL looked only at the cross-section of the factory tray piece (inspecting the splice if and only if it was supplied) and nothing more.

But all that sounds perfectly safe? No worries if there is no longer enough metal to carry 400A 600V safely back to the source winding? A steel cable tray can only take 600A anyway..

 

[roger]

So in your view if the manufacturer says "do it" then it's okay.

Pretty much

A foreign manufacturer can come here with product designed for foreign regulations, simply claim it meets NEC requirements, and everything is great?

Never said that, do you know the difference between "listed" and "approved"?

Because that is exactly what happened with wire mesh basket tray. The French brought it here without making a single change or concession to the NEC. UL looked only at the cross-section of the factory tray piece (inspecting the splice if and only if it was supplied) and nothing more.

I never said UL was perfect either but, NEC 110.3 includes the word "shall" and 90.7 would be of interest too.

But all that sounds perfectly safe? No worries if there is no longer enough metal to carry 400A 600V safely back to the source winding? A steel cable tray can only take 600A anyway.

I'm not real sure what you are asking, but the reality is, if a NRTL has tested and listed a piece of equipment (NRTL's including UL don't approve anything) it is accepted by the NEC.

If at sometime some reason comes forth that there are new requirments (read about raintight EMT fittings) then the listings can be removed and the new requirements can be out into play, this may be the avenue you need to take your concerns.

Roger

 

[jim dungar]

No worries if there is no longer enough metal to carry 400A 600V safely back to the source winding? A steel cable tray can only take 600A anyway..

This is only a concern if the tray is being used as the EGC. If it is not an EGC the cross sectional area is of no concern. Judgement can not be passed until the installation is completed.

 

[don_resqcapt19]

...Again, UL does NOT look at installation instructions for wire mesh basket tray. They look at cross-sectional area and splice hardware (if supplied - if not supplied UL assumes it will be done correctly). UL has not tested or approved anything like the modifications made in the photos I attached to my original post. Nothing like that is or can be listed or approved. There are no instructions included in the listing or labeling!

UL is on record as saying that they do look at all manufacturer's instructions and that all such instructions are 110.3(B) instructions. (this is a position that I don't agree with, but it is the official position of UL)

 

[rbalex]

Let?s begin by recognizing that cable tray is ?[a] unit or assembly of units or sections and associated fittings forming a structural system used to securely fasten or support cables and raceways.? [Underline mine] [See 392.2] As such, it is NOT a raceway nor is it required to be listed by the NEC although local jurisdictions may require it.

Suitability as an EGC is a permitted use, not a mandatory requirement.

If perchance it happens to be listed, field modification may indeed void the listing; nevertheless, it may still be reasonably identified and approved. (All italicized terms are defined in Article 100.)

I would not use wire-mesh systems as EGCs. Then again, in my dominant industry, which uses tons of cable tray, we don?t use any form of cable tray as EGCs either ? even aluminum ones with a 2 square inch cross section.

 

[CAM]

Wire Basket Fittings

Wire Basket Fittings

I am not sure this is clear and understood by all here - it is not my intention to bash wire mesh basket tray. The product concept is a good one (when adapted to US regulatory environment) and affords significant advantages versus ladder, center spine, or trough cable trays for many applications.

The problem, again, is that when the concept was imported from France it came with zero change or accommodation to the NEC. It was introduced to the low voltage installers because that was viewed as the least problematic market. Over a decade later and now we're seeing it on many electrical jobs where the issues with field modification of listed or labeled products as well as the current carrying capacity are critical.

There are at least five manufacturers of fittings - NEC 392.5(E) - for wire mesh basket tray as illustrated above. The fittings are UL classified as Equipment Ground Conductors and require no field removal of cross section during installation.

The consensus here seems to be that, at a minimum, the cutting/bending practice imported from the French is questionable depending on the location and what will be installed in the tray. And since most here are contractors or engineers rather than inspectors (from whom I have separately solicited opinion weighing 90%+ against cutting/bending), my question evolves into "Why cut/bend and take any chances when UL fittings are readily available?" We know there has been little adverse Code enforcement historically, but as more basket tray is used for electrical power and knowing most polled inspectors opinions against such severe field modification, we can probably expect more adverse enforcement in the future.

 

[jim dungar]

"Why cut/bend and take any chances when UL fittings are readily available?"

It comes down to the absolute fact that:
If the tray is not being used as an EGC, there is no violation of anything.

 

[CAM]

It comes down to the absolute fact that:
If the tray is not being used as an EGC, there is no violation of anything.

Really? Are you the AHJ there? In what jurisdiction? I can give you dozens of the largest metropolitan markets (and several States) in the US where the chief inspectors have unequivocally stated the opposite. Not once has an inspector ever even brought it up. They have stated that cutting/bending IS a violation of:
392.5(A), (B), (C), (D). They have also said they will not accept the modification of the UL labeled products as depicted in the photos provided in my original post.

 

[roger]

Really? Are you the AHJ there? In what jurisdiction? I can give you dozens of the largest metropolitan markets (and several States) in the US where the chief inspectors have unequivocally stated the opposite. Not once has an inspector ever even brought it up. They have stated that cutting/bending IS a violation of:
392.5(A), (B), (C), (D). They have also said they will not accept the modification of the UL labeled products as depicted in the photos provided in my original post.

And once again, no matter how much you dislike it, Hoffman allows it and includes it in their instructions, which means an inspector would have to allow it as well.

What is your real issue here?

Roger

 

[iwire]

Here in MA the inspector is actually specifically mandated by changes to 90.4 to accept listed products when used per the listing.

 

[qcroanoke]

my question evolves into "Why cut/bend and take any chances when UL fittings are readily available?"


$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

 

[jim dungar]

Really? Are you the AHJ there? In what jurisdiction? I can give you dozens of the largest metropolitan markets (and several States) in the US where the chief inspectors have unequivocally stated the opposite. Not once has an inspector ever even brought it up. They have stated that cutting/bending IS a violation of:
392.5(A), (B), (C), (D). They have also said they will not accept the modification of the UL labeled products as depicted in the photos provided in my original post.

Can you provide any written local code that prohibits these types of modifications? If not a written code, how about an official general ruling in writing, maybe something from a plan review, or is an automatic rejection of a UL classified item a surprise the chief inspectors spring after installation?

I have previously quoted how your simply picture can easily not in be in violation of any part of 392.5. potential violations depend only on how it is actually installed, just as it does with any other field modified product

Cable tray is not a UL Listed item, it is only UL classified. As such it is not a standard alone product and must be used with other UL devices. At least one manufacturer (Cooper B-Line) shows how many splice kits are required for their UL classification.
http://www.cooperbline.com/pdf/Flyers/UL-Classified-Splices.pdf
pages 2 and 3.

 

[CAM]

Cable tray is not a UL Listed item, it is only UL classified. As such it is not a standard alone product and must be used with other UL devices. At least one manufacturer (Cooper B-Line) shows how many splice kits are required for their UL classification.
http://www.cooperbline.com/pdf/Flyers/UL-Classified-Splices.pdf
pages 2 and 3.

And you will note that their last entry, the one for the 90 degree kit, which requires cutting the tray IS NOT UL Classified!

 

[CAM]

And once again, no matter how much you dislike it, Hoffman allows it and includes it in their instructions, which means an inspector would have to allow it as well.

Roger

Speechless. Completely speechless. Does that argument work on AHJ's in your market???

 

[roger]

Speechless. Completely speechless. Does that argument work on AHJ's in your market???

Absolutely, and even in FL. If an AHJ was to refuse to accept it they would have to make a formal amendment to 110.3(B). Are you use to AHJ's making up their own rules?

Once again, what is your real issue with this? Can you provide some documentation that shows catastrophic events, personal injury, property damage, or death that can be contributed to this practice?

Roger

 

[CAM]

Absolutely, and even in FL. If an AHJ was to refuse to accept it they would have to make a formal amendment to 110.3(B). Are you use to AHJ's making up their own rules?

Roger

I have statements from AHJ's in *major* metropolitan markets in FL, GA, DC, TX, AZ, CA, WA, NY, MD, NV, CO, NE, etc, all saying that this (cutting/bending basket tray) is a Code violation. I am not here to ask whether installers agree since it doesn't seem to matter. When I was a contractor, I never won an argument with an inspector and furthermore found the attempt extremely counter-productive.

Ironically, the best argument you posted was a manufacturer who does not have UL labeling on their product requiring cutting/bending. If you look to other top tier manufacturers (B-Line is a very good company) you'll find the same thing although sometimes hidden in fine print in the back where you see installation instructions.

You can try to argue the point and there's no penalty to arguing it with me because I do this for a living and don't mind at all. But the suggestion that one should ignore what the AHJ's have said and then argue with them is going to cost somebody a whole lot of money.

If you'd like I can post some of the AHJ's specific statements on the practice in question. Then again, if you don't work in major markets and have a local AHJ who you can push around then it's irrelevant to you and I don't understand what your interest is.

 

[CAM]

Fittings cost less

Fittings cost less

my question evolves into "Why cut/bend and take any chances when UL fittings are readily available?"


$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

I take this to mean you think the fittings cost more? Except that they do not. In fact, for all the manufacturers of which I am aware, it costs substantially less to buy a fitting than to send a couple guys with a bolt cutter to the jobsite for a day (at $75/hr or more loaded cost) where they butcher three sticks of tray to scrap before they get one that looks good enough to install. Add the benefit of never having lost time or injury claims for the constant cuts the guys will get from the razor sharp points of the cut wires and it's really not even a contest from a cost standpoint.

 

[roger]

I have statements from AHJ's in *major* metropolitan markets in FL, GA, DC, TX, AZ, CA, WA, NY, MD, NV, CO, NE, etc, all saying that this (cutting/bending basket tray) is a Code violation. I am not here to ask whether installers agree since it doesn't seem to matter. When I was a contractor, I never won an argument with an inspector and furthermore found the attempt extremely counter-productive.

Not meaning to sound cocky but, all I can say is I'm sorry. I have won a good number of challenges and even in FL.

Ironically, the best argument you posted was a manufacturer who does not have UL labeling on their product requiring cutting/bending. If you look to other top tier manufacturers (B-Line is a very good company) you'll find the same thing although sometimes hidden in fine print in the back where you see installation instructions.

You can try to argue the point and there's no penalty to arguing it with me because I do this for a living and don't mind at all. But the suggestion that one should ignore what the AHJ's have said and then argue with them is going to cost somebody a whole lot of money.

I'll let them challenge NEMA then. Let me direct you to (and maybe you should show this to the AHJ's you say agree with you) page 32 and 33 of this NEMA document so regardless of the NEC allowing it so does NEMA

You will have to set up an account at the NEMA site, it's easy and free.

If you'd like I can post some of the AHJ's specific statements on the practice in question. Then again, if you don't work in major markets and have a local AHJ who you can push around then it's irrelevant to you and I don't understand what your interest is.

I work in mostly large markets with very thorough and tough inspectors but, most know the NEC and will accept it when they make mistakes.

Before you post the AHJ's comments, please direct them to the NEMA link so they can tell us how they know more than NEMA.

In short, you don't have to ask installers anything, you're real battle is going to be with NEMA and the NEC 110.3(B)



Roger

 

[CAM]

Back to the point

Back to the point

Having taken the weekend off and given this a little thought, I'd like to get my question back on track. I'm here for market research purposes primarily. And the market for wire mesh basket tray is 100% commercial and predominantly in big cities. The "commercial" electrical guys in the small town where I lived for the last 20 years wouldn't know a basket tray from a shelf.

And I've been around the block a time or two and know how unnecessarily and pointlessly argumentative most online forums are. This one seems a little better than most, but I still see some argument only for the sake of argument.

Is there anybody here who is an active engineer or commercial contractor (and here I am looking for PM's not inside wiremen - we all know the inside wiremen get stuck with whatever the PM chooses most of the time regardless of whether it's right or wrong) who uses or has used basket tray on a large job?

And for the sake of full disclosure, for those who didn't look at my profile to see where my interests are, I am on the sales side of the business for a manufacturer. I have a deep understanding of what it takes to develop a product, get it through UL, and get it to market successfully. I also have around 10 years experience on the commercial side of electrical contracting in business development roles.

I'm interested in all constructive opinion, but if you're a residential electrician in farm country please don't argue about the Code applicability or how UL evaluates products - it's not helping anybody.