NFPA 79 Mandatory wire colors

So, I am covering for a colleague who is out this week, and I started to check out a control panel he had designed. To my surprise, I opened the door, and every single wire inside was grey!

Apparently, the customer this panel is built for has a spec for 7-stranded wire with a specific insulation. It sounds like all they could get (in a timely manner, not ALL they could get) was that specific wire in grey. The customer approved said panel change.

I popped open my NFPA 79 code and stared looking through the conductor sections. (see code excerpts below)

So, the first two paragraphs concerning the grounded conductor and interlocks both use the terminology “SHALL” which leads me to think there is NO interpretation. It sounds like the control circuit and power wiring could technically be gray? I’m not even sure what would be posted on the inside of the cabinet – all of the wire numbers and their voltages?

Is this panel a code violation? Personally, if I were working on this panel in the field, I would look at the panel and just say No Thanks, next please. Maybe there are industries that use all one color?

Code excerpts:

Section 13.2.3.1 Uses the terminology “..this conductor shall be WHITE, GRAY, or three continuous WHITE stripes on other than GREEN, BLUE, or ORANGE insulation along its entire length”

Section 13.2.4.1 “The color ORANGE shall be used to identify ungrounded conductors that remain energized when the main supply circuit disconnecting means is in the off position. This color identification shall be strictly reserved for this application only

Section 13.2.3.4 “Where color coding is used for identification of conductors, the following color codes shall be permitted to be used:
1. BLACK for ungrounded AC and DC power conductors
2. RED for ungrounded AC control conductors
3. BLUE for ungrounded DC control conductors
Where the identification is other than as permitted in 13.2.3.4, the means of identification shall be permanently posted on the inside of the main electrical control panel enclosure in a visible location.

even the code can be circumvented... the authority having jurisdiction part of the NEC says that they have the final say, and that could mean anyone from an EE to a store owner

>Maybe there are industries that use all one color?


1972 - My army buddy's 1966 International Harvester 1/2 ton pickup truck, every wire under the dash was green.

scott.lawrence said:

even the code can be circumvented... the authority having jurisdiction part of the NEC says that they have the final say, and that could mean anyone from an EE to a store owner

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The code can be made more stringent, not lax. The AHJ is not the EE or owner. It is the local government. The code can only be deviated by the AHJ if it is in a written, published form which is available to anyone doing electrical work in the jurisdiction.
Gray and white are reserved for use as grounded conductors. They are allowed to be used as other things under very specific circumstances. This situation does not meet the criteria. This panel sounds like a code violation to me, but most of the time it will not be seen by an electrical inspector so nothing will ever be said.

T Gibbs said:

The code can be made more stringent, not lax. The AHJ is not the EE or owner. It is the local government. The code can only be deviated by the AHJ if it is in a written, published form which is available to anyone doing electrical work in the jurisdiction.
Gray and white are reserved for use as grounded conductors. They are allowed to be used as other things under very specific circumstances. This situation does not meet the criteria. This panel sounds like a code violation to me, but most of the time it will not be seen by an electrical inspector so nothing will ever be said.

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the NFPA 70 2017 NEC disagrees...


*Article 100, Authority Having Jurisdiction


Informational Note:


.... In many circumstances, the property owner or his or her designated agent assumes the role of the authority having jurisdiction; at governmental installations, the commanding officer or department official may be the authority having jurisdiction

Originally posted by T Gibbs:

Gray and white are reserved for use as grounded conductors.

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that isn't what NFPA79 13.2.3.1 says. All it says is that the neutral, if present, must be a specific color. It DOES NOT say that the color used for neutral is reserved for the neutral conductor, like it does for the grounding conductor and the conductors that remain energized.

As much as this tends to offend all our sensibilities, assuming that the conductors are all labeled (meaning color is not used as wire identification) I think this design is technically compliant.

We are covered on 13.2.3.1, since EVERYTHING is gray.

It was never stated that there are any external connections in the panel so at this point I will assume we are covered for 13.2.4.1.

Presumably we are using labels so the conductors are identified by a means other than color so I don't think 13.2.4.3 is necessary.

I don't think I would want a panel like this but that doesn't mean it isn't compliant.

Keith

I had never read that note about the AHJ. I'm assuming that is under special circumstances. I know around here the AHJ is the state or city electrical inspector.

National Electrical Code article 200.7 DOES say that white, gray, or with three continuous white stripes shall only be used as the grounded conductor.

T Gibbs said:

I had never read that note about the AHJ. I'm assuming that is under special circumstances. I know around here the AHJ is the state or city electrical inspector.

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no special circumstances... the informational note is just to enforce the fact that the AJH is ultimately the deciding factor in what is/isn't applicable from the NEC.

T Gibbs said:

National Electrical Code article 200.7 DOES say that white, gray, or with three continuous white stripes shall only be used as the grounded conductor.

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pretty sure you mean 200.6, since 200.7 lists it's permissible uses.



but 200.6 is limited to sizes 6AWG or smaller... on larger, you can get by with tape at just the termination points 200.6 (B)(4)




and section E's exceptions state that you can use whatever color is available in a multi-conductor provided you mark it at the termination points....

NFPA 79 only applies to controls for "industrial machinery" as defined in its own standard under section 3.3.55. It is NOT the same as the NEC and is only applicable if the AJH SAYS it is applicable, a concept known as "adoption by reference", meaning IF the AHJ (or end user) SAYS in a specification that a control panel will be built to NFPA 79 standards, then it applies. If not referred to, it does not.


I ran into this once a long time ago with some panels I built for the Army COE going on a dam, where the specifications called for all control wiring to be sone using tinned extra flexible stranded wire with SIS insulation (SIS = Silicon Insulated Switchboard wire), which was only available at that time in grey. I tried to argue this same issue; that it would violate NFPA 79, and was given a schooling on the validity of NFPA 79 by the COE engineers.