Adhesive sticker labeling on outdoor equipment acceptable?

solburden

New member
Is adhesive sticker labeling on outdoor PV equipment acceptable? NEC 110.21 Marking, does not specifically address this only dictating the marking is suitable for the environment it is placed in. My opinion is that if the label meets IFC, ANSI and UL 969 requirements, then an adhesive sticker is acceptable. That being said, I would like to garner additional feedback on this from the community at large.

Thank you in advance for your time!
 
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jaggedben

Senior Member
Is adhesive sticker labeling on outdoor PV equipment acceptable? NEC 110.21 Marking, does not specifically address this only dictating the marking is suitable for the environment it is placed in. My opinion is that if the label meets IFC, ANSI and UL 969 requirements, then an adhesive sticker is acceptable. That being said, I would like to garner additional feedback on this from the community at large.

Thank you in advance for your time!
What I've seen in the field on older systems is the labels always still there, but the color and printing totally faded to white by the sun.

In other words, I think that the adhesives used are not really an issue, but UV resistance is a big one.
 

GoldDigger

Moderator
Staff member
What I've seen in the field on older systems is the labels always still there, but the color and printing totally faded to white by the sun.

In other words, I think that the adhesives used are not really an issue, but UV resistance is a big one.
Metallic surface with only black lettering or engraved lettering are pretty dependable.
 

tsamples

Member
Location
Oregon
Is adhesive sticker labeling on outdoor PV equipment acceptable? NEC 110.21 Marking, does not specifically address this only dictating the marking is suitable for the environment it is placed in. My opinion is that if the label meets IFC, ANSI and UL 969 requirements, then an adhesive sticker is acceptable. That being said, I would like to garner additional feedback on this from the community at large.

Thank you in advance for your time!
First of all, in Oregon you need to be looking in the Oregon Solar Installation Specialty Code, which trumps the NEC. Secondly, the wording in the code is "permanently attached label or other approved means". A stick on label is not permanently attached. Oregon Building Codes Division is training all of the inspectors in solar installations (it will take some time), and in the training one of the things to look for is metallic or phenolic labelling, screwed or rivetted in place. A handy guide being passed out to inspectors and installers alike is the "Field Inspection Guideline for PV Systems" from Interstate Renewable Energy Council (www.IRECUSA.org). As one of two electrical inspectors for Eastern Oregon, I can tell you that a stick-on paper label is not an "approved means" and is not acceptable to the authority having jurisdiction (AKA, me).
 

GoldDigger

Moderator
Staff member
First of all, in Oregon you need to be looking in the Oregon Solar Installation Specialty Code, which trumps the NEC. Secondly, the wording in the code is "permanently attached label or other approved means". A stick on label is not permanently attached. Oregon Building Codes Division is training all of the inspectors in solar installations (it will take some time), and in the training one of the things to look for is metallic or phenolic labelling, screwed or rivetted in place. A handy guide being passed out to inspectors and installers alike is the "Field Inspection Guideline for PV Systems" from Interstate Renewable Energy Council (www.IRECUSA.org). As one of two electrical inspectors for Eastern Oregon, I can tell you that a stick-on paper label is not an "approved means" and is not acceptable to the authority having jurisdiction (AKA, me).
Will your inspectors accept epoxied in place labels for those who do not feel good about driving screws or rivets into the equipment?
Are your inspectors going to overreach and try to control labels affixed to components by their manufacturer or is this only for additional special labels required by the Code?

Nice document, BTW. The actual installation photos add a lot to its usefulness.
 
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jaggedben

Senior Member
A stick on label is not permanently attached. Oregon Building Codes Division is training all of the inspectors in solar installations (it will take some time), and in the training one of the things to look for is metallic or phenolic labelling, screwed or rivetted in place.
I have to say I have a hard time with that, too. Am I supposed to penetrate the housing of a listed inverter to attach signage, for example? I agree with Goldigger on the expoxy, and I think perhaps some of the adhesives have come far enough to be dependable as well.
 
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petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
what is not permanent about adhesive labels?

I don't have an issue with the AHJ deciding that something more substantial be used but plastic nameplates don't always fair all that well in the sun and heat either and often fail.
 

George Stolz

Moderator
Staff member
Location
Windsor, CO NEC: 2017
Occupation
Service Manager
First of all, in Oregon you need to be looking in the Oregon Solar Installation Specialty Code, which trumps the NEC. Secondly, the wording in the code is "permanently attached label or other approved means". A stick on label is not permanently attached. Oregon Building Codes Division is training all of the inspectors in solar installations (it will take some time), and in the training one of the things to look for is metallic or phenolic labelling, screwed or rivetted in place. A handy guide being passed out to inspectors and installers alike is the "Field Inspection Guideline for PV Systems" from Interstate Renewable Energy Council (www.IRECUSA.org). As one of two electrical inspectors for Eastern Oregon, I can tell you that a stick-on paper label is not an "approved means" and is not acceptable to the authority having jurisdiction (AKA, me).
Call me confused. 110.21 is primarily centered around manufacturers labeling their equipment, and I expect that manufacturers have subjected their equipment to a healthy amount of testing prior to turning their equipment over to the UL to do yet more testing.

If a listed piece of equipment is labeled as required in 110.21 do you routinely reject the equipment for having a stick-on label?

If I put a label (such as required by 110.24) inside the door of a service, not subject to rain or sun, is that not acceptable? It would be for most inspectors in my area.

It sounds from the tone of your post that perhaps the responsibility of being "one of two inspectors in Eastern Oregon" has in some way skewed your perception of your role of being a servant to the people of Oregon overseeing the "practical safeguarding" ambitions of the NEC, to something else.
 

jaggedben

Senior Member
:lol:
Pardon my laughing at a mental image of somebody trying to punch numbers on a phenolic sign.
...
No kidding. For large commercial jobs ordering custom plastic might be appropriate. For all the resi stuff I do, keeping track of the orders and numbers would just be insane, would lead to stupid delays and lost time and money. I know you can get a machine and make your own, but still...

BTW, the last time I talked to a sign maker about this, they said that phenolic material has been banned (or at any rate is no longer available) due to environmental concerns. There's a different material (can't recall the name, begins with an 'r' I think) that they offered as a substitute that is also UV resistant, and looks and feels the same.
 
Is adhesive sticker labeling on outdoor PV equipment acceptable? NEC 110.21 Marking, does not specifically address this only dictating the marking is suitable for the environment it is placed in. My opinion is that if the label meets IFC, ANSI and UL 969 requirements, then an adhesive sticker is acceptable. That being said, I would like to garner additional feedback on this from the community at large.

Thank you in advance for your time!
I would say if you have the manufacturer's data on outdoor life expectancy of the sign as well as a maintenance inspection procedure that calls for the replacement of the signs after their life expectancy, you'll leave no room for the inspector for argument.

As a practical matter the sign's life expectancy selected should not exceed the life expectancy of the equipment unless it is more cost efficient than the laternative. Ex. a SS engraved sign's life would exceed a PV cells'.
 

GoldDigger

Moderator
Staff member
As a practical matter the sign's life expectancy selected should not exceed the life expectancy of the equipment unless it is more cost efficient than the laternative. Ex. a SS engraved sign's life would exceed a PV cells'.
But there are not a lot of other choices with a maintenance-free life span of 20+ years.
Brass or bronze will be stolen. :)
 
First of all, in Oregon you need to be looking in the Oregon Solar Installation Specialty Code, which trumps the NEC. Secondly, the wording in the code is "permanently attached label or other approved means". A stick on label is not permanently attached. Oregon Building Codes Division is training all of the inspectors in solar installations (it will take some time), and in the training one of the things to look for is metallic or phenolic labelling, screwed or rivetted in place. A handy guide being passed out to inspectors and installers alike is the "Field Inspection Guideline for PV Systems" from Interstate Renewable Energy Council (www.IRECUSA.org). As one of two electrical inspectors for Eastern Oregon, I can tell you that a stick-on paper label is not an "approved means" and is not acceptable to the authority having jurisdiction (AKA, me).
tsamples, I'm glad to see you and the other AHJs are looking at the IREC documents provided, they have a great deal of information and guidance provided in them. I have not fully reviewed the materials you reference but I would hope you (and they) would consider a "stick on" label that is manufactured for this very specific application as acceptable . Making a blanket requirement for metallic or phenolic labeling screwed or riveted in place seems misguided to me. A "stick on paper label" sounds like something I print in my office on my inkjet printer, and I would fully agree that kind of solution is not proper.

It is also worth pointing out that in OR, the OR Electrical Specialty Code (OESC) is what trumps the NEC. The OR Solar Installation Specialty Code is purely a structural code, it has no electrical component to it. There are brief references to the OESC and one Appendix includes a copy of OESC amendments, but those are only for reference and convenience.
 
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Zee

Senior Member
Location
CA
I have nothing to add re Code requirements.

What I do find:
1. one materials approach does not fit all situations: even within one job.
2. The sun will destroy everything unless metal. Matter of time.
(e.g. I just "saw" the mnfctr. labels on PV modules underside completely washed out and snow white after 10 years or so.)

That said, I do not use metal.
~ There are desktop label printers with "extra strong adhesive" laminated label rolls available, claiming UV resistance, for the custom labels (DC Disco V and I , AC Disco V and I, etc)
~ There are excellent stickers (Hellerman-Tyton) made for UV and solar applications. I wonder if these aren't in fact better than a phenolic (or equivalent) placard???
Some are "metallic", akin to the DMV tag you may stick on your license plate.
~ Finally, in addition to labeling the outside, Sun-beaten surface, I have been placing (just laying inside) or sticking labels inside boxes (especially CB on roof, MSP, subpanel, dc disco, ac disco, etc).
"Warning line and load.....", "Do not disconnect under load".... these are critical, and i find i sleep better when i have one inside the box.
 
I have nothing to add re Code requirements.

What I do find:
1. one materials approach does not fit all situations: even within one job.
2. The sun will destroy everything unless metal. Matter of time.
(e.g. I just "saw" the mnfctr. labels on PV modules underside completely washed out and snow white after 10 years or so.)

That said, I do not use metal.
~ There are desktop label printers with "extra strong adhesive" laminated label rolls available, claiming UV resistance, for the custom labels (DC Disco V and I , AC Disco V and I, etc)
~ There are excellent stickers (Hellerman-Tyton) made for UV and solar applications. I wonder if these aren't in fact better than a phenolic (or equivalent) placard???
Some are "metallic", akin to the DMV tag you may stick on your license plate.
~ Finally, in addition to labeling the outside, Sun-beaten surface, I have been placing (just laying inside) or sticking labels inside boxes (especially CB on roof, MSP, subpanel, dc disco, ac disco, etc).
"Warning line and load.....", "Do not disconnect under load".... these are critical, and i find i sleep better when i have one inside the box.
:thumbsup: A man speaking from - obvious - experience. Great post!
 
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