Wire Colors

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fifty60

fifty60

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I am trying to get a better understanding of international wire colors. Here in the US, NFPA 79 dictates the following:

Black = AC power at line voltage
Red = AC power at less than line voltage
White; neutral Gray = AC Neutral conductor at less than line voltage
Blue = Ungrouded DC power
Blue/white stripe or white/blue stripe = DC grounded voltage
Orange or Yellow = excepted voltage that may be energized while the main disconnect is in the off position
Green; Green w/yellow stripe = equipment grounding conductor

I would like to get some input on what standards have authority for industrial machines in other countries like....UK, Canada, China, India. If anyone could give examples and references to the standards. My end goal is try to harmonize, to the best that I can, the wire colors that I use. I would like to, for example, be able to pass a UL inspection and still retain my CE Marking.
 
Whoever is going to do your listing is a good source for that information. You tell them what you have and they tell you what standards it has to meet. You have to start with the sales dept who will confer with engineers to decide what standards it has to meet. Once you have submitted your project you will have direct contact with a lead engineer at UL or whatever entity you use for listing services.
 
There is no way that I can see to have a UL508a listed panel meet CE requirements as far as color coding goes short of wiring the whole thing in some kind of MC cable.
 
petersonra said:
There is no way that I can see to have a UL508a listed panel meet CE requirements as far as color coding goes short of wiring the whole thing in some kind of MC cable.
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I believe he manufactures industrial machinery.
 
There are few requirements for wire color in the NEC. Neutral must be gray or white, while ground green or bare. Any color is good for phase. The standard for 120/208 tends to be black, red, blue, white neutral, green ground. Phase B is required by the NEC to be orange if its a High leg 120/208/240 Delta system.

277/480Y tends to be brown,orange,yellow, gray neutral, green ground. However you can technically use any wire color as long as its not for the neutral or High leg.

Internationally for Britian the wire colors are as pictured:View attachment 9021 Note they have since changed so they can harmonize with the rest of Europe, the colors on the right.
 
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Use of orange for high leg not required

Use of orange for high leg not required

NEC 110.15 and 230.56 require that the high leg be marked, but not necessarily orange. It could also be marked by "other effective means". (I use orange, but I did win a lunch over this.) Are any of you finding that many use purple on the B phase of a 480Y/277 volt system? I've run into this over and over, even on projects that have no high leg on the premises. WTF? All that's required is a plaque on a high leg panel stating "Caution________ Phase Has ______ Volts to Ground." 408.3(F)(1).
 
petersonra said:
what industrial machinery is UL listed?
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Perhaps more to the point, where does the NEC say anything about the color of internal wiring in machinery? It will tell you what colors to use in a portable power cord or fixture whip.
The UL standard for some listed products like panelboards and controls does specify colors.
 
GoldDigger said:
The UL standard for some listed products like panelboards and controls does specify colors.
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Like Black for all 'line voltage' circuits, Red for all 'AC control' circuits, and blue for 'DC control'.
The only thing in common with the NEC would be the use of green and white, although UL is a little more tolerant of the use of colored tracer markings on them.
 
ghorwood said:
NEC 110.15 and 230.56 require that the high leg be marked, but not necessarily orange. It could also be marked by "other effective means". (I use orange, but I did win a lunch over this.) Are any of you finding that many use purple on the B phase of a 480Y/277 volt system? I've run into this over and over, even on projects that have no high leg on the premises. WTF? All that's required is a plaque on a high leg panel stating "Caution___B_____ Phase Has __415____ Volts to Ground." 408.3(F)(1).
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Correct, should have read it rather than going by experience:slaphead: But I have never seen it not being orange either on a High leg. Yup! I have seen a few installs with all of the B phase as purple (all were Y grounded), but in most applications its usually 277v switch legs as purple being a traveler.
 
NEC does not dictate what wiring colors shall be inside of Industrial Panel, but NFPA 79 does. I listed the colors above from NFPA 79. So, obviously there does not seem to be an efficient way to set up the wire coloring scheme so that it is portable to what UL, CSA, and CE are looking for. Any recommendations on a good approach to trying to get it this way? I think the ground wire is about the only thing that is portable across the standards...
 
fifty60 said:
I am trying to get a better understanding of international wire colors. Here in the US, NFPA 79 dictates the following:

Black = AC power at line voltage
Red = AC power at less than line voltage
White; neutral Gray = AC Neutral conductor at less than line voltage
Blue = Ungrouded DC power
Blue/white stripe or white/blue stripe = DC grounded voltage
Orange or Yellow = excepted voltage that may be energized while the main disconnect is in the off position
Green; Green w/yellow stripe = equipment grounding conductor

I would like to get some input on what standards have authority for industrial machines in other countries like....UK, Canada, China, India. If anyone could give examples and references to the standards. My end goal is try to harmonize, to the best that I can, the wire colors that I use. I would like to, for example, be able to pass a UL inspection and still retain my CE Marking.
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Here's my experience with getting anything listed.

I'm assuming you want to get something listed so you can sell listed product (industrial machines).

There is what I call the "parent listing" and that is the standard under which your product will be listed. For me, it's UL 916 Energy Management Equipment. Then there are potentially infinite other standards which have to be followed. I have a plug blade assembly, a thermoplastic housing, a printed circuit board, critical components, a socket, external wiring, internal wiring, etc. and all of them have one or more other standards which they too must comply with; I call these the "child listings". I find it faster and cheaper to find subassemblies from products already listed and supply those listing reports with my submittal.

It looks like you want to coordinate your wiring colors such that no matter what country you go to for listing, it will be compliant affording you opportunity to manufacture your product to be exported to any country without having to make sub-model A for the USA, sub-model B for the EU, sub-model C for Asia, etc. I commend that. The more complicated anything is, the less the chance of being able to come up with a "one size fits all" design. Of course voltage and frequency are the first things which come to mind.

As to those questioning why industrial machines would be UL Listed, industrial machines vary from small soldering stations to mega-ton presses and everything in between.

My advice is to contact UL and request a quote for listing in the countries you want. They can do more than just the USA and likely every country you want. In the quote they will tell you what "parent" standards they are going to list your product under. Fell free to pop the wiring color question on them during the quote process. They are very helpful.

If I'm misunderstanding your inquiry or objective, feel free to say so.
 
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I believe UL 508 would probably be the primary Parent Listing for my machine. I am controlling heaters, compressors, blowers, and solenoids from an industrial control panel. Any other Parent Listings that would come to mind from this? Any child listings?

What is NFPA 79 considered as? I know it would not be a Parent Listing...but how can I express my machine is compliant with NFPA 79?

It is difficult trying to harmonize a product for the standards. Some items are easy, some more difficult. Transformers, for example, are much more expensive with the CE rating than without. I am trying to simplify things as much as I can, but am having a hard time finding the exact wiring requirements outside of NFPA 79. I would like to find similar lists for CSA and CE requirements..and any other for that matter....
 
fifty60 said:
I believe UL 508 would probably be the primary Parent Listing for my machine. I am controlling heaters, compressors, blowers, and solenoids from an industrial control panel. Any other Parent Listings that would come to mind from this? Any child listings?

What is NFPA 79 considered as? I know it would not be a Parent Listing...but how can I express my machine is compliant with NFPA 79?

It is difficult trying to harmonize a product for the standards. Some items are easy, some more difficult. Transformers, for example, are much more expensive with the CE rating than without. I am trying to simplify things as much as I can, but am having a hard time finding the exact wiring requirements outside of NFPA 79. I would like to find similar lists for CSA and CE requirements..and any other for that matter....
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Every time you read a listing it is going to reference more listings. Starting with that top (parent) listing is the best start, and only UL (or whatever independent lab is going to do your listing evaluation) can dictate that. My advice is to get a quote from UL and have them specify what standard they are going to use. From that information you can make informed decisions as to cost & time to get other labs to quote the same work. But nothing beats a UL logo on a product; it's the Cadillac of the industry. When I worked in a building department I would have inspectors fail inspections because something is not "UL Listed" and as many times as I told them to reference (then) Chapter 35 in the building code for the list of "approved independent testing laboratories" they just don't get it. My advice is pay the money and wait the time for UL to do the actual evaluation. They charge a little more and take a little longer (lead time issue) but it's a business decision you have to make.

Back to your questions & statements:

Any other Parent Listings that would come to mind from this? Any child listings? No and I would feel horrible if I mislead you. UL does not charge a fee for a quote and they'll turn it around pretty quick. In the time you've been on this thread, they could have had it to you already. Not knocking your means & methods, just trying to give advice (which is what this venue is for).


It is difficult trying to harmonize a product for the standards. I concur. I have a plug blade under ANSI C136.10 in the USA and the BS (British Standard) has geometry that is very close but just a couple thousandths different. It's technically impossible to comply with both but we'll see what productivity yields. Just tooling and lead time on a new plug blade will be around $80k and 6 months, and then I'll have to start again with getting my plug blade assembly listed (child standards, as we've been calling them).

Transformers, for example, are much more expensive with the CE rating than without. I think it's more of a matter of non-listed product being bootleg product. There's cost associated with listing evaluation, manufacturing facility evaluation, listing maintenance, etc. But remember you only need "recognized" components in your assembly (not listed components) and as long as you use them within their "recognized" specifications, you'll sail right through your listing evaluation.

Once your product is evaluated, it's time to evaluate the manufacturing facility which gets its own listing.

Back to square one: Call UL and speak to a sales person. Tell them you want to get a quote on a listing evaluation and describe your product. From that information he'll know what division to send it to (don't be spooked if he sends it to the HVAC division because they do controls and they're qualified). Once you get into a "division" the engineers will take your description and specify the standard under which it needs to be evaluated. Tell them up front you want to do USA, EU, etc.

Good luck! It's an interesting process. I sailed through everything first time but then again I have 35 years experience in regulatory compliance. You can hire 3rd party consultants to navigate the process for you but I don't think we're allowed to mention specific companies on here. Send me a PM if you like.
 
Mgookin, thanks for the input. I will follow your advice for obtaining the relevent UL Parent/Child listings. My current focus is on CE. The process is straight forward. We have 2 primary directives to meet 1) low voltage 2)EMC. To satisfy the directives we have to follow Harmonized Standards that lay out the technical details to meet the Directive.

It seems like the CE process is more "contained" than the UL process. I know, however, they are apples and oranges.

I am interested in UL 61010. The same UL document has been adopted as a harmonized standard for the Low Voltage Directive, and is called IEC 61010. I am trying to figure out how UL uses 61010. Would they use it as a "parent listing" towards the goal of UL listing our...appliance (not technically an industrial machine). The appliance has a sub panel, so UL-508 would also most certainly come into play.

Like you said, I should call UL and get their input on this. I am focused primarily on CE at the moment, but trying to see how to weave it all together into a great efficient product that makes sense and is safe. I like what I am learning from CE. It puts a lot of responsibility on the manufacturer, and also produces a safer end product.
 
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