ECN Forum
Posted By: Niko 210.5 (C) enforce? - 10/15/10 09:31 PM
If you are installing a 2 wire AC or MC cable in a building that has 480-277V 240-120V, the code says the ungrounded conductor has to be reidentified for each system. My question is:

Do you special order MC or AC cable with different colored ungrounded conductors or use 2 conductor cable and re-identifiy the conductor?

I may have read that smaller than #4 can not be reidentified (exception do apply to grounded conductors).

Posted By: LEO_304E Re: 210.5 (C) enforce? - 10/15/10 10:18 PM
Originally Posted by Niko
If you are installing a 2 wire AC or MC cable in a building that has 480-277V 240-120V, the code says the ungrounded conductor has to be reidentified for each system. My question is:

Do you special order MC or AC cable with different colored ungrounded conductors or use 2 conductor cable and re-identifiy the conductor?

I may have read that smaller than #4 can not be reidentified (exception do apply to grounded conductors).

You can buy type M/C &A/C cable with the different color Brown Orange Yellow for 480/277volts but it is not used that much out there. on the larger cables we use tape to re idetifie at splice points , but on #10 #12 Circuits we just mark the box covers with the voltage smile
Posted By: Niko Re: 210.5 (C) enforce? - 10/16/10 01:26 AM
I appreciate your feedback,

Is #6 and smaller conductors allowed to be re-identified from black to other finish?

i believe it can't but i can't find the code section.
Posted By: wewire2 Re: 210.5 (C) enforce? - 10/16/10 04:18 AM
I find it a little confusing. 200.6 states that #6 and smaller shall be identified by a continuous white or gray outer finish on other than green wire along its entire length. So it seems that you could apply a finish layer of tape along the entire wire.(lots of work!) However,if you read the detailed interpretation in the handbook it states
"for 6 AWG or smaller, identification of the grounded conductor solely by distinctive white or gray marking at the time of installation is not permitted except as described for flexible cords and multiconductor cables" .......
So, by the interpretation, are they saying that you cannot mark it, as in a few wraps of tape at the termination or are they saying you cannot re-identify it at all for use as a neutral? The rules for identifying a #6 or smaller green wire read the same except 250.119 states that you can't use a green wire as a neutral(grounded conductor)
except for a particular low voltage exception. Any comments anyone?
Posted By: Niko Re: 210.5 (C) enforce? - 10/16/10 04:45 AM
For the grounded conductor it says smaller than 6 you can't re-identify the conductor. another words if need a grounded conductor and all you have on the truck is #8 black, you can't use the black# 8 and wrap phase tape.
So for grounded conductor #4 and larger you can use phase tape at the time of termination.

But my questions is for smaller than #4 ungrounded conductors, can they be re identified?
Posted By: wewire2 Re: 210.5 (C) enforce? - 10/16/10 05:29 AM
It just says you can't re-identify it with a mark. A mark is a small token label such as a wrap of tape.
In my opinion, it's really up for AHJ interpretation since the wording is not specific enough to know the
real intention.
Posted By: Scott35 Re: 210.5 (C) enforce? - 10/16/10 06:44 AM
Niko;

Quote

But my questions is for smaller than #4 ungrounded conductors, can they be re identified?


I see no reason why UNGROUNDED CONDUCTORS sized smaller than #4, may not be identified at the Terminations.

Viewing the Articles and Sections involved with Conductor Identification:

-------------------
-------------------

A: Identification of GROUNDED (AKA "Neutral") Conductors:
Article 200
Section 200.6

Conductor Identification = White or Gray...

Sizes Where Identification Methods change:

  • #4 and Larger may be identified at accessible Termination points (Colored Tape wraps at ends);
  • #6 and smaller to be continuously Color Coded (White or Gray Insulation).


.................................................

B: Identification of EQUIPMENT GROUNDING (AKA "Grounding") Conductors:
Article 250
Section 250.119

Insulated Conductor Identification = Green (or Green with one or more Yellow Stripes)...

Sizes Where Identification Methods change:

  • #4 and Larger may be identified at accessible Termination points (Colored Tape wraps at ends)...
    Section = 250.119(A);
  • #6 and smaller to be continuously Color Coded (Insulation Color to be Green)...
    Section = 250.120(C).


................................................

C: Identification of UNGROUNDED - HIGH VOLTAGE PHASE (AKA "High-Leg") Conductors:
Article 110
Section 110.15

Insulated Conductor Identification = Orange...

Sizes Where Identification Methods change:
N/A.

Qualifying Notes:
On 3 Phase 4 Wire Delta Systems, the Conductor or Bus Bar Kit(s) with the High Voltage to Ground Phase shall Identified with Orange Color Coding.
At locations on the System where a Grounded ("Neutral") Conductor is present, the High Voltage Phase shall be Identified by Orange Tagging.

No indications of Continuous Color Coding per sizes.
Identification Compliance is stated for tagging methods to be made at Connection Points - specifically where the System Grounded Conductor also exists.

.....................................................

D: Identification of UNGROUNDED (AKA "Hot") Conductors - for more than ONE (1) Premises Wiring Systems:
Article 210
Section 210.5(C)

Insulated Conductor Identification = Anything other than Green, White or Gray (not indicated verbatim in Section 210.5(C), but indirectly referenced in Articles 200, 215, 230, 250, 310, and 400)...

Sizes Where Identification Methods change:
N/A

Qualifying Notes:
No indications of Continuous Color Coding per sizes.
Identification Compliance is stated for tagging methods to be made at Accessible Points - specifically for Branch Circuitry where more than One (1) Nominal Voltage System exists on the same Premises.

< end code compliance references >
__________________________________________________________

According to the defined Sections, Ungrounded Conductors may be Identified at Termination Points, and Points of Accessibility (i.e.: Panelboards, Switchboards, Motor Controls, Pullboxes, etc.).
Identification is not required at Conduit Bodies (i.e.: LBs)

My opinion / view of the intentions behind the Size Specific Identification Methods for Grounded and Equipment Grounding Conductors, is the nominal applications where they would commonly be used per given sizes.
For example, Conductors sized #4 and larger would normally be relevant to Feeder Installations; whereas Conductors sized #6 and smaller would normally be relevant to Branch Circuitry.

In the case of Branch Circuitry, EGCs may be sized similar to the Ungrounded Conductors - more apparent with 15 Amp, 20 Amp and 30 Amp Branch Circuits.

Where Branch Circuit Conductor sizes have been increased for Voltage Drop compensation, the EGC size would also be increased, matching the size of the Active Branch Circuit Conductors.

Similar conditions would be experienced with Grounded Branch Circuit Conductors, in regards to the 15 Amp, 20 Amp and 30 Amp "Commonly Used" Branch Circuits.
The possibility for numerous Junction Boxes and Outlets being involved with Branch Circuits, appears to be the logic continuous Color Coding for "Smaller Conductors" - tagging the ends may not be feasible, and likely will not provide an effective permanent method.

Where Feeders are installed, they tend to be limited in access points, i.e.: Single Point-To-Point runs between...

  1. Source (Service or Distribution Section)

    and
  2. Application (Panelboard or Transformer)


Junction / Pull Points may or may not exist in Feeder runs.
Where these Access Points exist, the tagging method would be more effective, as the likelihood of QUALIFIED PERSONNEL gaining Access at these Points, _SHOULD_ be able to Identify the installation as a "Feeder".
They "-Normally-" would not be Accessing the Box, with intentions of connecting a small Load to an existing Wiring System...
This statement is highly debatable, however I am unsure of the best way to describe this possibility!

So, in conclusion;
The NEC does not directly place Restrictive Definitions on the Identification of Ungrounded Conductors per Specific sizes, per the Sections listed above. Only Identification at Terminations and Accessible Points is described.

By "Restrictive Definitions", I mean:

MANDATORY RULES: - Terms characterized as "Shall" and "Shall Not" (Specifically Required or Prohibited)

And / Or;

PERMISSIVE RULES: - Terms characterized as "Shall Be Permitted" and "Shall Not Be Required" (NOT Specifically Required or Prohibited).

Hope this reply offers some assistance.

Scott
Posted By: wewire2 Re: 210.5 (C) enforce? - 10/16/10 07:22 AM
Hi Scott

You wrote
"#6 and smaller to be continuously Color Coded (Insulation Color to be Green)...
Section = 250.120(C)."

250.120 (C) Refers to the protection of conductors smaller than #6
250.119 Just says that the outer finish needs to be green not the insulation.

Posted By: Scott35 Re: 210.5 (C) enforce? - 10/16/10 10:41 AM
wewire2;

Thanks for the response!

Man, I don't know why I placed the 250.120(C) reference!
I do not remember smoking any Crack - never smoked it before AFAIK wink

Per the Section reference, the following Addendum is issued:

"#6 and smaller to be continuously Color Coded (Insulation Color to be Green)...
Section = 250.119."

Text verbatim:

"Individually covered or
insulated equipment grounding conductors shall have a
continuous outer finish that is either green or green with
one or more yellow stripes except as permitted in this
section.
{A}

Conductors with insulation or individual covering
that is green, green with one or more yellow stripes, or
otherwise identified as permitted by this section shall not
be used for ungrounded or grounded circuit conductors."


Exception to the above Mandatory Note {A} is 250.119(A); EGCs larger than #6.

Now I must consume Raven (eat Crow), so I must go!

Scott
Posted By: wewire2 Re: 210.5 (C) enforce? - 10/16/10 07:44 PM
Haha! Scott you do great! Your posts are appreciated.
Posted By: Tesla Re: 210.5 (C) enforce? - 10/16/10 07:45 PM
When using MC, AC -- which are bundled factory colors -- the Code permits #6 thru #14 to be re-identified. Think switch-legs.

That option does NOT exist for EMT runs where it is obvious that the correct color can be pulled in at no extra expense.

Of late, there is a trend to use fully covered feeders. Very handy.

On all commercial jobs out my way we see mixed 277 and 120 volt grounded distribution. Yes, separate colors and MC are ordered.

Because the neutral for the 120 run is 30 degrees delayed behind the 277 neutral -- they CANNOT run on the same conductor. That's why the Code has the OP's noted provision.

BTW, delta and wye diagrams come from Tensor Mathematics. When you drop the tensor diagram for a Wye transformer inside the Delta tensor you can see that the three legs split the interior vee's in half. So...

Each Vee = 60 degrees
Cut in two = 30 degrees
So when delta waves are transformed into wye functions they lag by 30 degrees -- because the media is an inductor.

If, for any reason, these neutrals get crossed over you get terrific harmonics on them as 'circulating current.'
Posted By: gfretwell Re: 210.5 (C) enforce? - 10/16/10 10:05 PM
Caution
:opinion bit on:
When I think "reidentifiy" I think "change type of conductor" (like like using white for an ungrounded conductor). If you are using other than green, gray or white as ungrounded conductors any additional tape is just informational, not reidentification. (like putting B O Y tape on a black 12ga wire to signify it is 480v)
I agree they do make MC cable in a wide variety of configurations/colors and if I was wiring a whole building I would get some but I don't think the code requires that I buy it if I am just hooking up a troffer on a 408/277 wye. AFC doesn't seem to be bragging about having violet/gray anyway. I would put violet tape on the hot tho.
Posted By: Niko Re: 210.5 (C) enforce? - 10/16/10 10:28 PM


Quote
That option does NOT exist for EMT runs where it is obvious that the correct color can be pulled in at no extra expense.


I guess this is what i am looking for. What is the code reference?

Posted By: gfretwell Re: 210.5 (C) enforce? - 10/17/10 12:23 AM
If you are looking for a reference to putting purple tape on a black wire and using it for an ungrounded conductor, I don't think you can find a rule against it.
All of the reidentification rules I know are in articles about grounded and grounding conductors. (green, gray and white ID going one way or the other)
Posted By: Niko Re: 210.5 (C) enforce? - 10/17/10 04:13 AM
[quote]
Originally Posted by gfretwell
If you are looking for a reference to putting purple tape on a black wire and using it for an ungrounded conductor, I don't think you can find a rule against it.


That is what i was looking. as i mentioned before, i was under the impression that re-ID of smaller colored insulated conductor was not allowed.

Thank you all.
I Learn something new everyday.
Posted By: gfretwell Re: 210.5 (C) enforce? - 10/17/10 08:12 AM
That is my opinion, your mileage may vary. wink

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