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Thread: Old EGC style, which code cycle?

  1. #1
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    Old EGC style, which code cycle?

    I have a California residence built in 1962.


    The EGC is a bare 14 awg wire run separately to metal outlet boxes in the kitchen, bathrooms, garage and outdoor boxes. It generally follows the 12 awg fabric wrapped NM, but not always, usually under the same staples and branches off with barrel crimped additions as needed, even to different circuits. The EGC is bonded to the boxes with grounding clips. Non-bonded boxes, such as switch boxes, are made of Bakelite.

    It is an interesting solution. I am wondering which NEC code cycle this stopped being practiced, and when did grounding conductors need to be included in the cable. My searches has been fruitless.

  2. #2
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    Quote Originally Posted by KWillis View Post
    I have a California residence built in 1962.


    The EGC is a bare 14 awg wire run separately to metal outlet boxes in the kitchen, bathrooms, garage and outdoor boxes. It generally follows the 12 awg fabric wrapped NM, but not always, usually under the same staples and branches off with barrel crimped additions as needed, even to different circuits. The EGC is bonded to the boxes with grounding clips. Non-bonded boxes, such as switch boxes, are made of Bakelite.

    It is an interesting solution. I am wondering which NEC code cycle this stopped being practiced, and when did grounding conductors need to be included in the cable. My searches has been fruitless.
    FWIU, Nm with a reduced size egc in the jacket was available in the the late '50s (a lot of contractors didn't use it and instead did what you mentioned above, as the egc reqs were spotty at the time) and become commonplace around the time the code required all recs to be grounded in 1962 (your house was built then, but may not have adopted the '62 NEC at the time of construction....)- I don't know when the NEC dictated an egc be included in the jacket- I'd imagine it would be around that same time. NM with a full size egc was mandated around 1970 or so....

    What you described is very typical for that time period- only recs in certain areas (like the areas you mentioned) were required to be grounded. One old NEC rule was that metal boxes within x number of feet of grounded objects (plumbing) were to be grounded- you'll see grounded boxes/ recs in old kitchens near the sink, but the ones near the dinner table across the room won't be.

    They would also bond the metal shell light fixtures in those areas by running that separate egc beside the 2w nm to the ceiling box- very common to see the light and even the light switch box in an old bath grounded thru an egc snaked thru the wall and clamped to the old galvanized plumbing.

    FWIW, the separate egc method is still sort of permitted- see 250.130(C)
    Last edited by user 100; 10-10-17 at 11:23 PM.

  3. #3
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    Quote Originally Posted by user 100 View Post
    FWIU, Nm with a reduced size egc in the jacket was available in the the late '50s (a lot of contractors didn't use it and instead did what you mentioned above, as the egc reqs were spotty at the time)
    Wow. I've lived a sheltered life. And I worked as an apprentice during my summers in college and installed that ole' reduced EGC NM in a lot of new construction.

    I've never seen that kind of installation. I can imagine it was a way to use up the existing stock of non-EGC NM . . .

    I can also imagine that is was a way to give an inspector what the new Code required . . .

    I agree that the 1962 NEC was the edition of the Code that introduced the requirement that all receptacles be grounding type. The rules in the '62 edition would have only gone into effect when adopted by the local AHJ where this "1962 residence" was built.

    KWillis, what you describe sounds like the last edition BEFORE the 1962 NEC, where there was a list of the dwelling receptacle locations that were required to grounding type. As for the method of a separate bare EGC with barrel crimp spliced extensions as needed. . . well, that is just another possible way to "skin the cat". Compared to some of the other "solutions" to having an EGC, what you describe seems rather reasonable and effective.
    Another Al in Minnesota

  4. #4
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    Starting in 1947, a reduced EGC was allowed only if it was included in the cable assembly.

    The 1968 NEC first required a full-size EGC.

  5. #5
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    Quote Originally Posted by 480sparky View Post
    Starting in 1947, a reduced EGC was allowed only if it was included in the cable assembly.

    The 1968 NEC first required a full-size EGC.
    That's interesting Ken. Thanks !

    I'd have loved to have been in the room when the code making panel developed that one.
    Another Al in Minnesota

  6. #6
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    Quote Originally Posted by 480sparky View Post
    Starting in 1947, a reduced EGC was allowed only if it was included in the cable assembly.
    And I wonder what constitues a cable assembly. Being a bundle of wires under the same staple?

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    Quote Originally Posted by KWillis View Post
    And I wonder what constitues a cable assembly. Being a bundle of wires under the same staple?
    Factory listed assembly. ie, the ground inside the sheath.

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    Quote Originally Posted by KWillis View Post
    And I wonder what constitues a cable assembly. Being a bundle of wires under the same staple?
    There is a definition of "cable", as used in the NEC, published in the 2016 NFPA Glossary of Terms that says a cable is "A factory assembly of two or more conductors having an overall covering."

    So, no, that field assembly you describe in the OP isn't a cable.

    You can Google NFPA Glossary of Terms to read a copy.
    Another Al in Minnesota

  9. #9
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    Quote Originally Posted by 480sparky View Post
    Starting in 1947, a reduced EGC was allowed only if it was included in the cable assembly.

    The 1968 NEC first required a full-size EGC.
    That wasn't in article 336, I assume 250?
    Brian John
    Leesburg, VA

  10. #10
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    Quote Originally Posted by brian john View Post
    That wasn't in article 336, I assume 250?
    Rule 2595.

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