Ok, I always seem to get these, spend countless hours researching, come up with nothing and then bug you guys on these forums - I guesss I am trying to say Thank you! Anyway, I have a 3 phase rotary phase converter, manufactured by American Rotary. The unit is installed and everything looks good, inspector has no problem there. But as he was walking away, he asked about the UL listing, there is not one on the control panel. I called the manufacturer and they said the components are all UL listed, TRUE, including the hoffman enclosure... But the assembly is not. And that it is usually (???) not a problem. Now I have to have an answer for my inspector - Any suggestions short of throwing this $1000 bucks in the trash and buying one from someone else?
UL listed components vs UL listed assembly
- Thread starter Horst1
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IMO, if the components are all individually listed you are good to go.
After we have wired a house with listed components, do we have to call a third party testing lab to come list the wiring and fixtures in said house as an assembly before we can get an electrical final?
Roger
After we have wired a house with listed components, do we have to call a third party testing lab to come list the wiring and fixtures in said house as an assembly before we can get an electrical final?
Roger
davidr43229
Senior Member
- Location
- Columbus, Oh
I suspect this was an industrial site? If so, what state?
While the manufacturer gave your a "lame" answer, I don't know that your Inspector will accept your response. I hope he does. The Manufacturer is not required to List a panel, however most are, due to this very scenario you have just painted.
Residential is far different than Industrial. The Inspector was probably referring to UL508A and NEC 409, would be my guess. I am sorry I don't have a good answer to give to you.
Just my $.02
davidr43229 said:
David, the good answer is, if the components are listed individually all is fine, we are not talking about a system (as in series rated) here.
If you didn't like the house as an example, tell me how many commercial building installations are listed as assemblies?
This is where it seems as though inspectors are relying on a crutch to approve something instead of their knowledge.
Roger
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davidr43229
Senior Member
- Location
- Columbus, Oh
Roger we are talking about an assembly (Industrial Controller) , not a building.
Just because you use UL Listed parts, does not make the Industrial Controller ok...
I think that is what the Inspector is driving at, perhaps not....
Just because you use UL Listed parts, does not make the Industrial Controller ok...
I think that is what the Inspector is driving at, perhaps not....
tony_psuee
Senior Member
- Location
- PA/MD
"...before we can get an electrical final?"
Roger,
IMO the part of your response I quoted is the key. The house is still undergoing a third party inspection. That inspection is of the wiring methods to ensure they comply with the safety standard in place in that area, NEC. I will go out on a limb and say that UL tests the listed components used in a house or commercial building based on them being installed to the NEC requirements. So, if the wiring passes the final everything is good. For this situation, without having a UL or other NRTL listing there is no 3rd party of the wiring methods and total assembly safety. My suggestion would be to contact UL and get a price for a field inspection of the device. If it passes they will apply a UL label.
tony
Roger,
IMO the part of your response I quoted is the key. The house is still undergoing a third party inspection. That inspection is of the wiring methods to ensure they comply with the safety standard in place in that area, NEC. I will go out on a limb and say that UL tests the listed components used in a house or commercial building based on them being installed to the NEC requirements. So, if the wiring passes the final everything is good. For this situation, without having a UL or other NRTL listing there is no 3rd party of the wiring methods and total assembly safety. My suggestion would be to contact UL and get a price for a field inspection of the device. If it passes they will apply a UL label.
tony
tony_psuee said:
Tony, if I am using a listed control transformer, a listed relay and base, a listed enclosure, and listed conductors to provide switching for say an Xray in use light, why would it need to be listed as an assembly?
This would simply be a money maker for a testing lab, nothing more as far as safety is concerned.
Roger
tony_psuee
Senior Member
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- PA/MD
Yes and no
Yes and no
"This would simply be a money maker for a testing lab, nothing more as far as safety is concerned."
Roger,
I agree with the first part of the sentence and not the second. We could both design the circuit you used as an example with the difference that I used a smaller enclosure. Because we are flush with cash, submit for listing. Yours passes and mine fails. My smaller enclosure results in heat issues that looking at the individual component info is not apparent. We both used all listed components and mine has safety issues because I tried to cut corners with component cost or wanted a smaller installation footprint.
tony
Yes and no
"This would simply be a money maker for a testing lab, nothing more as far as safety is concerned."
Roger,
I agree with the first part of the sentence and not the second. We could both design the circuit you used as an example with the difference that I used a smaller enclosure. Because we are flush with cash, submit for listing. Yours passes and mine fails. My smaller enclosure results in heat issues that looking at the individual component info is not apparent. We both used all listed components and mine has safety issues because I tried to cut corners with component cost or wanted a smaller installation footprint.
tony
- Location
- Simi Valley, CA
Wow this is an interesting discussion.
If we take a look at 110-3(A)(1-8) these are several of the things that UL would be looking at and taking into consideration. If you want the inspector to make the determination that you have a "control panel" then you would have to supply him with a lot more information than a UL label on the different components.
Now the catch to this. If it were a UL listed "control panel" then the parts installed would only have to be labeled UR.
While my thought would be to approve it because you did use all UL listed parts, I'm not disinclined to agree with Tony.
Also remeber there are other third party testing labs besides UL that are a lot cheaper and quicker that can field test your equipment.
If we take a look at 110-3(A)(1-8) these are several of the things that UL would be looking at and taking into consideration. If you want the inspector to make the determination that you have a "control panel" then you would have to supply him with a lot more information than a UL label on the different components.
Now the catch to this. If it were a UL listed "control panel" then the parts installed would only have to be labeled UR.
While my thought would be to approve it because you did use all UL listed parts, I'm not disinclined to agree with Tony.
Also remeber there are other third party testing labs besides UL that are a lot cheaper and quicker that can field test your equipment.
tony_psuee said:
Tony, I agree, a listing doesn't allow us to use the product incorrectly, if the enclosure is to small, it is to small, and an inspector would have legitimate reason to tag the installation.
OTOH, have you seen how much room is in some manufacturers relay/contactor enclosures? I wouldn't ever design an enclosure this tight simply for the reason I would want more room for working and landing the conductors.
Roger
RayS
Senior Member
- Location
- Cincinnati
Horst1 said:
I have run into the inspector requiring a label on the control panel- we can usually get a third party agency to review and label it locally.
tony_psuee
Senior Member
- Location
- PA/MD
Roger,
I have seen and worked in enclosures that although listed were extremely difficult to work in. As you know, UL or other NRTL isn't a confirmation of a good design, only it meets a minimum safety standard. I think some manufacture's must hate the folks that wire their products.:smile:
tony
I have seen and worked in enclosures that although listed were extremely difficult to work in. As you know, UL or other NRTL isn't a confirmation of a good design, only it meets a minimum safety standard. I think some manufacture's must hate the folks that wire their products.:smile:
tony
dbuckley
Senior Member
- Location
- Canterbury, New Zealand
roger said:
The problem is, the listing does allow you to use the product incorrectly.
Back to an enclosure that is too small; if you have a number of listed items that produce heat, someone needs to work out what heat removal arrangements are appropriate. The manufacturer of (eg) the relay can't, as he doesn't know what other heat producing stuff will be in the same box. He can only give the specs of his individual item. So the designer / builder of the panel needs top work these issues through, preferably leaving a documentation trail behind.
It's no different for the inspector; how is he supposed to work out that the half a dozen listed bits in a box are compatible with each other and the box they are in?
All these problems go away if you have a listed "thing", as then someone has certified it works as a unit.
The underlying problem is regulatory mechanisms can't accommodate variations in complexity. The xray sign mentioned earlier; any competent person can design and build such a thing, and come up with a sign that is "safe", within reasonable definitions of the word. But howzabout a panel with a bunch of relays, contactors, a PLC, a UPS, and a single board computer, not to mention annunciator lights, breakers etc. How many of us are competent to design such an arrangement and certify to an acceptable standard that the complete assembly is a goodun? Thats why insurance companies and regulators like listing organizations.
dbuckley said:
Yeah right.
I (the company I work for) have been involved in some legal issues over listed equipment and the testing lab (very well known one at that) that listed them, so don't bank on it.
I will continue to live by the fact that if the components are "listed for the use" all is fine.
If I purchase, or a manufacturer sends me a manufactured assembly, I will agree that the assembly needs to be listed as an assembly, but a field made item only needs listed parts, and in some cases I would say listed parts aren't even necessary
Roger
dbuckley
Senior Member
- Location
- Canterbury, New Zealand
roger said:
I agree there fully. But will the insurance company? Ultimately, in business, most of the time, they are the only jurisdiction that matters.
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
Go back to the issue raised early on; it depends upon what state you are in. First off though, the NEC stops short of requiring UL labels on assemblies. But article 409 does require an SCCR label (Short Circuit Current Rating). If there is a label from an NRTL (the technical term for agencies like UL and ETL), the SCCR label would now be part of that process. Article 409 provides for alternate methods of attaining an SCCR rating, but once you go down that path you open yourself up to having to provide proof to the inspector that you knew what you were doing and how you came to your conclusions. He may or may not accept your methodology and proof, he (the AHJ) is ALWAYS the ultimate authority don't forget.
Now back to the state issue. SOME states, such as most of those in the West, have amendments to their code that require NRTL labels on any assemblies with 5 or more components in a box (the number may vary), OR, you can ask for a variance if you are an industrial facility with an engineering staff etc. That rule (bought and paid for by Boeing and other large users in the mid 1980's) is complicated and not applicable to any homeowner I know of. So if you are, for instance, in California the inspector can indeed ask for an overall UL label on the control panel of the phase converter, whether or not the components inskde are UL listed.
Now back to the state issue. SOME states, such as most of those in the West, have amendments to their code that require NRTL labels on any assemblies with 5 or more components in a box (the number may vary), OR, you can ask for a variance if you are an industrial facility with an engineering staff etc. That rule (bought and paid for by Boeing and other large users in the mid 1980's) is complicated and not applicable to any homeowner I know of. So if you are, for instance, in California the inspector can indeed ask for an overall UL label on the control panel of the phase converter, whether or not the components inskde are UL listed.
davidr43229
Senior Member
- Location
- Columbus, Oh
Jraef,
Well said ! per the NEC 2005. It's only when the AHJ is asking for the UL Listing that the Manufacturer, such as American Rotary will have to conform, rather than saying "Well all our components are UL listed", which again was a lame answer to the OP.
This will be a topic for years to come.
Just my $.02
Well said ! per the NEC 2005. It's only when the AHJ is asking for the UL Listing that the Manufacturer, such as American Rotary will have to conform, rather than saying "Well all our components are UL listed", which again was a lame answer to the OP.
This will be a topic for years to come.
Just my $.02
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