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  1. #1
    Jake Guerrero's Avatar
    Jake Guerrero Guest

    Default Using 2 conductor cable for 240 volt circuits

    I inspected a remodel yesterday with all new wiring and main/distribution panel. The electrician used 2 conductor cable on all the 240 volt circuits.

    There were 2 HVAC units with electric heat, and 2 condensing units, and a dryer receptacle.

    This guy used the white sheathed wire for the 2nd 'hot' conductor and painted it black with a marks-a-lot. He used the bare copper i'm assuming as the neutral, which leaves all the equipment without an equipment ground (or thats the way I see it). So he calls me today, and tells me the city ok'd it and gave him a green tag, and thats theres nothing he can do about it; he says its ok.

    So i'm looking in the IRC trying to find the section that would require equipment to have a seperate grounding conductor. I'm looking at E3808.9. Is there somewhere else I should be looking?

    Does anyone else have any insight on this..?

    Thanks,
    Jake

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  2. #2
    Join Date
    Mar 2007
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    Default Re: Using 2 conductor cable for 240 volt circuits

    Jake, if it is straight 240 Volt equipment, you don't have a neutral, just two hots and a ground. If you have a dryer that has 120 volt motor and/or components (as almost all dryers do) then you need a neutral.
    Water heaters, etc. don't need a neutral.
    Jim

    Jim Luttrall
    www.MrInspector.net
    Plano, Texas

  3. #3
    Join Date
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    Default Re: Using 2 conductor cable for 240 volt circuits

    Ditto. That threw me off the first time I saw it, but straight 220 won't have a neutral. I was used to seeing dryer and range wiring, which always had the neutral present. I'm surprised that they marked the white wire. That's considered overkill by electricians in my area.

    Jim Robinson
    New Mexico, USA

  4. #4
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    Default Re: Using 2 conductor cable for 240 volt circuits

    Quote Originally Posted by Jake Guerrero View Post
    ... with all new wiring ...

    There were 2 HVAC units with electric heat, and 2 condensing units, and a dryer receptacle.
    Nope, not allowed. "All New" is the key, if it was 'old', then that would have been allowed to the dryer and the range, but not with "new" wiring.

    This guy used the white sheathed wire for the 2nd 'hot' conductor and painted it black with a marks-a-lot.
    Borderline maybe okay ... but probably not. Many of those markers fade over time, meaning it is not "permanently re-identified" "by painting or other effective means".

    He used the bare copper i'm assuming as the neutral, which leaves all the equipment without an equipment ground (or thats the way I see it).
    Actually, he used the bare ground as a ground, there is no neutral for 240 volt circuits, except for the range and the dryer, which need all four wires.

    So he calls me today, and tells me the city ok'd it and gave him a green tag, and thats theres nothing he can do about it; he says its ok.
    I'd tell him there is something he can do about it, fix it.

    Every HI will tell you that most of the thing we find were supposedly 'signed off by the city or county', yet they are wrong.

    So i'm looking in the IRC trying to find the section that would require equipment to have a seperate grounding conductor. I'm looking at E3808.9. Is there somewhere else I should be looking?
    SECTION E3808
    GROUNDING

    (This entire section.)

    E3808.4 Effective ground-fault current path.
    Electrical
    equipment and wiring and other electrically conductive material
    likely to become energized shall be installed in a manner
    that creates a permanent, low-impedance circuit facilitating the
    operation of the overcurrent device. Such circuit shall be capable
    of safely carrying the maximum ground-fault current likely
    to be imposed on it from any point on the wiring system where a
    ground fault to the electrical supply source might occur.

    E3808.9 Equipment fastened in place or connected by permanent
    wiring methods.
    Noncurrent-carrying metal parts of
    equipment, raceways and other enclosures, where required to
    be grounded, shall be grounded by one of the following methods:
    1. By any of the equipment grounding conductors permitted
    by Sections E3808.8 through E3808.8.3.
    2. By an equipment grounding conductor contained within
    the same raceway, cable or cord, or otherwise run with
    the circuit conductors. Equipment grounding conductors
    shall be identified in accordance with Section E3307.2.


    Last but not least (actually more important than many think):

    E3301.2 Scope.
    Chapters 33 through 42 shall cover the installation
    of electrical systems, equipment and components
    indoors and outdoors that are within the scope of this code,
    including services, power distribution systems, fixtures, appliances,
    devices and appurtenances. Services within the scope of
    this code shall be limited to 120/240-volt, 0- to 400-ampere,
    single-phase systems. These chapters specifically cover the
    equipment, fixtures, appliances, wiring methods and materials
    that are most commonly used in the construction or alteration
    of one- and two-family dwellings and accessory structures regulated
    by this code. The omission from these chapters of any
    material or method of construction provided for in the referenced
    standard NFPA 70 shall not be construed as prohibiting
    the use of such material or method of construction. Electrical
    systems, equipment or components not specifically covered in
    these chapters shall comply with the applicable provisions of
    the NFPA 70.



    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  5. #5
    Jake Guerrero's Avatar
    Jake Guerrero Guest

    Default Re: Using 2 conductor cable for 240 volt circuits

    Thanks Jim L., Jim R., and Jerry.

    I think the marks-a-lot painted wires threw a signal at me. There still maybe be an issue with the dryer receptacle.

    Hopefully the buyer's will view it as cautiousness on my part to have it looked at.

    Jake


  6. #6
    John Steinke's Avatar
    John Steinke Guest

    Default Re: Using 2 conductor cable for 240 volt circuits

    Apart from the dryer, all seems OK to me.

    It is very possible that the air conditioner, etc., will not need a neutral. As others have noted, the remaining wire is correctly being used as a ground wire.

    Using tape, or a marker, is in fact a marking method recognized by the NEC- especially in the case of a cable assembly. Sure, there have been discussions as to the meaning of "permanent," but such hair-splitting flies in the face of both accepted trade practice and common sense.

    To argue otherwise would be, in effect, to argue that the code required 240v circuits to be wired in pipe, flex, or some other means that allows you to pull individual wires. Or, perhaps, to argue that the code required you to run cable with a neutral wire, even if the load did not require a neutral.
    I doubt that any would make those arguments.


  7. #7
    Join Date
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    Default Re: Using 2 conductor cable for 240 volt circuits

    Quote Originally Posted by John Steinke View Post
    Using tape, or a marker, is in fact a marking method recognized by the NEC- especially in the case of a cable assembly.
    Tape is recognized as being acceptable when re-identifying black to white, or black to red, etc. There is no requirement for that re-identification to be "permanent". If white tape comes off a black wire leaving a black wire, 'it is assumed to be hot', unlike black tape coming off a white wire leaving it white, 'it is assumed to be *not hot*'.

    Re-identifying white to black is where the re-identification is required to be "permanent", and the code even states "by painting or other effective means". "Tape" is not permanent, "tape" comes loose and falls off.

    Sure, there have been discussions as to the meaning of "permanent," but such hair-splitting flies in the face of both accepted trade practice and common sense.
    While it does fly in the face of common practice, so did requiring equipment grounding wires when they came in. As did requiring GFCI protection, as well with AFCI protection. Only some die hard, you are not changing my ways, old electricians fail to see the light and the reasoning and refuse to change to a "permanent" method *as required by code*.

    To argue otherwise would be, in effect, to argue that the code required 240v circuits to be wired in pipe, flex, or some other means that allows you to pull individual wires. Or, perhaps, to argue that the code required you to run cable with a neutral wire, even if the load did not require a neutral.
    Nope. You can buy NM cable with whatever colors you want in there. You can buy NM cable for 240 volt circuits which has two blacks, or a black and a red, and an equipment ground, and no white.

    The only requirement is that you have to buy it by the large reel, which means planning ahead, and it most likely mean 'large electrical contractor wiring a large job'.

    For those who do not fit the above, the code allows the alternative by way of "permanent" re-identification.

    When I was helping Mike Holt with his video on the changes to the 2005 NEC, one of the people on the panel was from wire supplier and another was from a large electrical distribution company which ships worldwide - both stated that it is no problem ordering whatever colors you want in NM cable, you are only limited by your need and ordering by the reel.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

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