Does screwing onto the front cover of a panel board/ control panel prevent UL listing?

[jim dungar]

According to UL:

"It is the responsibility of the authority having jurisdiction (AHJ) to determine whether any modifications are significant enough to require a UL staff member to evaluate the modified product. UL can assist the AHJ in making that determination"

From this I infer that not all field modifications automatically void a UL Listing.

 

[jap]

Yeah this seems like a no brainer. How would drill two small holes in the cover change anything? I've seen many panelboard covers with field installed hasps and locks too.

Me too,,,, and makes me throw up in my mouth just a little bit every time I see it.

JAP>

 

[electrofelon]

According to UL:

"It is the responsibility of the authority having jurisdiction (AHJ) to determine whether any modifications are significant enough to require a UL staff member to evaluate the modified product. UL can assist the AHJ in making that determination"

From this I infer that not all field modifications automatically void a UL Listing.

Perhaps it is semantics, but I would take it further and say there isn't such thing as "voiding a listing". The NEC requires components to be acceptable and approved by the AHJ. Listing is one way an AHJ may approve products.

 

[electrofelon]

Me too,,,, and makes me throw up in my mouth just a little bit every time I see it.

JAP>

Try having a little more faith in yourself and your fellow electricians. We are licensed professionals, and IMO , should a fair amount of free reign to do what we need to do in the field even if that involves "modifying" equipment. We are not talking about rearranging the bus bars in a switchboard here.

 

[jap]

To me it's about the look.

I can generally look at any label,hasp,lock, hinge etc that's been bolted on to an enclosure in the field by someone and immediately tell it's not from the factory.

Not that it would be a violation as much as they just never seem to look quite right in my opinion.

JAP>

 

[infinity]

Try having a little more faith in yourself and your fellow electricians. We are licensed professionals, and IMO , should a fair amount of free reign to do what we need to do in the field even if that involves "modifying" equipment. We are not talking about rearranging the bus bars in a switchboard here.

I agree, think about the final product and what you've done because screwing something onto the cover isn't modifying anything.

 

[jap]

Try having a little more faith in yourself and your fellow electricians. We are licensed professionals, and IMO , should a fair amount of free reign to do what we need to do in the field even if that involves "modifying" equipment. We are not talking about rearranging the bus bars in a switchboard here.

Oddly enough I've field bent parallel runs of 1/4 x 4" copper buss bar to revamp 4000 amp bussways into existing switchboards and made it look more factory than most can make a hinge, hasp or label look on the front of a loadcenter.

Just sayin.

JAP>

 

[kwired]

To me it's about the look.

I can generally look at any label,hasp,lock, hinge etc that's been bolted on to an enclosure in the field by someone and immediately tell it's not from the factory.

Not that it would be a violation as much as they just never seem to look quite right in my opinion.

JAP>

Even an adhesive label with some other electrician's contact information on it never seems to look right though

Worse yet is when other service people (non electricians) put their contact information labels on it.

 

[electrofelon]

Oddly enough I've field bent parallel runs of 1/4 x 4" copper buss bar to revamp 4000 amp bussways into existing switchboards and made it look more factory than most can make a hinge, hasp or label look on the front of a loadcenter.

Just sayin.

JAP>

And even that I don't have a problem with in certain situations.

I am quite libertarian on lugs. I have removed bolts from bus bar joints in switchboards to add lugs.

 

[jap]

And even that I don't have a problem with in certain situations.

I am quite libertarian on lugs. I have removed bolts from bus bar joints in switchboards to add lugs.

Some Industrial plants don't have much choice.
Old gear, new bussway.
I've done a ton of transitions.

 

[jaggedben]

Perhaps it is semantics, but I would take it further and say there isn't such thing as "voiding a listing". The NEC requires components to be acceptable and approved by the AHJ. Listing is one way an AHJ may approve products.

All we mean by void the listing is if you make a modification to where the equipment would no longer pass the UL requirements. The problem is if you aren't intimately familiar with those requirements you don't necessarily know which modifications would do that.

And if the code requires something to be listed, then it's certainly the AHJ's prerogative to quiz you about whether the manufacturer approves of your modifications and demand field listing if the manufacturer doesn't back you up. And in my experience the manufacturer rarely gives us the benefit of the doubt because why should they accept the liability instead of putting it on us.

 

[wwhitney]

All we mean by void the listing is if you make a modification to where the equipment would no longer pass the UL requirements.

So if the enclosure is a NEMA 1 enclosure, I don't see how using screws or rivets to attach a label to the front cover would meet the above threshold.

Now if it's a NEMA 3R enclosure, I could see a potential issue as far as water ingress. Which is probably why you are used to using adhesive labels.

Cheers, Wayne

 

[infinity]

And even that I don't have a problem with in certain situations.

I am quite libertarian on lugs. I have removed bolts from bus bar joints in switchboards to add lugs.

For large sectional switchgear the bus comes as separate pieces that get installed in the field to put the sections together. Large CT's require that the bus be completely removed so that the POCO CT's can be installed. Removing and reinstalling bus, support brackets, insulators, etc. is all part of installing larger equipment. Certainly if the listing is okay with that a few screws in the cover won't change a thing.

 

[jap]

All we mean by void the listing is if you make a modification to where the equipment would no longer pass the UL requirements. The problem is if you aren't intimately familiar with those requirements you don't necessarily know which modifications would do that.

And if the code requires something to be listed, then it's certainly the AHJ's prerogative to quiz you about whether the manufacturer approves of your modifications and demand field listing if the manufacturer doesn't back you up. And in my experience the manufacturer rarely gives us the benefit of the doubt because why should they accept the liability instead of putting it on us.

Finally,,,,, an explanation of the conversation my parents had with me after I cut the muffler off their car when I was 15....

JAP>

 

[roger]

I guess we shouldn't have installed THESE in the numerous pieces of gear we installed them in if a screw or pop rivet ruins it.

 

[jap]

I guess we shouldn't have installed THESE in the numerous pieces of gear we installed them in if a screw or pop rivet ruins it.

Fluke's got it figured out.

 

[jaggedben]

So if the enclosure is a NEMA 1 enclosure, I don't see how using screws or rivets to attach a label to the front cover would meet the above threshold.

Now if it's a NEMA 3R enclosure, I could see a potential issue as far as water ingress. Which is probably why you are used to using adhesive labels.

Cheers, Wayne

Rivets probably fine. Screws ... depends how long and pointy they are.

In all serious I've seen as many accidental shorts in residential from people replacing panel cover screws with longer and pointier ones as from anything else.

 

[wwhitney]

Screws ... depends how long and pointy they are.

312.11(A)(2) requires a 1" air space between the door of a cabinet and any live metal parts. So screw length for a sign on the door of an enclosure like shown in the OP is regulated, if opening it reveals live metal parts.

Cheers, Wayne

 

[paulengr]

According to UL:

"It is the responsibility of the authority having jurisdiction (AHJ) to determine whether any modifications are significant enough to require a UL staff member to evaluate the modified product. UL can assist the AHJ in making that determination"

From this I infer that not all field modifications automatically void a UL Listing.

It’s a big argument against UL 508A. The traceability requirements mean panel builders must record every single serial number of every component. This includes marking the serial number of the spool of wire on the wire list for every wire. Now reading this “backwards” changing any component or removing so much as a jumper in a 508A panel is a modification that exceeds its Listing. This is as opposed to NEC panels where the components and wiring carry their own Listing. Any sane AHJ though won’t read that far into it.

That logic also applies though to leaving space and adding extra IO or any similar and typical additions.

 

[paulengr]

Perhaps it is semantics, but I would take it further and say there isn't such thing as "voiding a listing". The NEC requires components to be acceptable and approved by the AHJ. Listing is one way an AHJ may approve products.

Yes there is. UL delisted Federal Pacific on certain breakers. And NEC and UL now both require physical removal of a Listing sticker if equipment is “modified” or refurbished. Again no exact definition of what that means. Since it is no longer Listed you’d have to pay for field inspection. There is an NFPA standard for what those entail. The documentation is over the top.