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Thread: 2014 NEC, 406.4(D)(2) Non–Grounding-Type Receptacles.

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    2014 NEC, 406.4(D)(2) Non–Grounding-Type Receptacles.

    Possibly someone can help me answer a question I have regarding: NEC - ‘406.4(D)(2) Non–Grounding-Type Receptacles.”


    My understanding of this code is that the old, not-grounded, 2-prong receptacles can be replaced with a GFCI receptacle, so long as the GFCI receptacle is marked, ”
    “GFCI Protected” and “No Equipment Ground.” This is clear.


    Can someone help me understand the NEC rationale for sub-paragraph (c)?


    Sub-paragraph (c) of this code states, “(c) .... Grounding-type receptacles supplied through the ground-fault circuit interrupter shall be marked “GFCI Protected” and “No Equipment Ground.” An equipment grounding conductor shall not be connected between the grounding-type receptacles.”


    Sub-paragraph (c), I don’t get. Why does the NEC on one had allow “Grounding-type receptacles s supplied through the ground-fault circuit interrupter “ and on the other hand say, “An equipment grounding conductor shall not be connected between the grounding-type receptacles.”



    Here’s my question: What’s the purpose for allowing grounding-type receptacles downstream from a non-grounded GFCI
    receptacle , if the NEC says you’re not permitted to plug a grounded 3-prong-plug (equipment grounding conductor ) into that receptacle? Why not just use 2-prong receptacles marked “GFCI Protected” downstream from the non-grounded GFCI receptacle since 3-prong plugs at those outlets are not permitted according to to my read of 406.4(D)(2)(c)?

    Thanks for your feedback.

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    Note the exact wording of the section you quoted is:
    An equipment grounding conductor shall not be connected from the ground-fault circuit interrupter type receptacle to any outlet supplied from the ground-fault circuit-interrupter receptacle.

    It does not prohibit you from plugging a 3 wire cord into the receptacle
    At my age, I'm accustomed to restaurants asking me to pay in advance, but now my bank has started sending me their calendar one month at a time.

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    Quote Originally Posted by augie47 View Post
    ... It does not prohibit you from plugging a 3 wire cord into the receptacle
    But for some loads 250.114 says you can't plug the 3 wire cord into that receptacle.
    Don, Illinois
    (All code citations are 2017 unless otherwise noted)

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    I think the intent recognizes that the first outlet in the string (i.e., the one that has the GFCI protection) does not have a ground wire coming in to it. The next part of the reasoning is that if you allow a ground wire to be run from that outlet to another outlet downstream, that ground wire will not be able to do its function (i.e., because there is no ground wire that goes all the way back to the panel). So why allow one to be installed, if it cannot do its job? Also (and I know this is weak), if a future installer sees a ground wire going into the second outlet, and it has been long enough since it was installed that all labels are lost or faded, how will they know there is no ground path back to the source? By not allowing a ground wire to be run from the first outlet to the second, a future installer will recognize right away (with or without seeing any labels) that there is not a complete ground path.
    Charles E. Beck, P.E., Seattle
    Comments based on 2017 NEC unless otherwise noted.

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    NV, welcome to the forum. One GFCI receptacle can be used to protect downstream receptacles in this case, too.


    Charlie, I believe the reason for not interconnecting EGC terminals is to make sure that an accidental energization of one load's cabinet, and thus its EGC, does not energize another load's EGC, and thus its cabinet.
    Code references based on 2005 NEC
    Larry B. Fine
    Master Electrician
    Electrical Contractor
    Richmond, VA

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    Quote Originally Posted by LarryFine View Post
    Charlie, I believe the reason for not interconnecting EGC terminals is to make sure that an accidental energization of one load's cabinet, and thus its EGC, does not energize another load's EGC, and thus its cabinet.
    That makes sense. Thanks, Larry.

    Charles E. Beck, P.E., Seattle
    Comments based on 2017 NEC unless otherwise noted.

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    Bad Read

    Quote Originally Posted by augie47 View Post
    Note the exact wording of the section you quoted is:
    An equipment grounding conductor shall not be connected from the ground-fault circuit interrupter type receptacle to any outlet supplied from the ground-fault circuit-interrupter receptacle.

    It does not prohibit you from plugging a 3 wire cord into the receptacle
    I think you're right. I misread subparagraph (c). There is no prohibition in using a 3-wire cord/plug. The prohibition is running a ground from the not-grounded gfci receptacle to its down stream receptacles. Bad misread on my part. Thanks for the clarification !!

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    Quote Originally Posted by charlie b View Post
    I think the intent recognizes that the first outlet in the string (i.e., the one that has the GFCI protection) does not have a ground wire coming in to it. The next part of the reasoning is that if you allow a ground wire to be run from that outlet to another outlet downstream, that ground wire will not be able to do its function (i.e., because there is no ground wire that goes all the way back to the panel). So why allow one to be installed, if it cannot do its job? Also (and I know this is weak), if a future installer sees a ground wire going into the second outlet, and it has been long enough since it was installed that all labels are lost or faded, how will they know there is no ground path back to the source? By not allowing a ground wire to be run from the first outlet to the second, a future installer will recognize right away (with or without seeing any labels) that there is not a complete ground path.
    To me, all of this if very weak indeed.

    The allowance of the GFI to be installed is because of the absence of an EGC in the first place.

    What difference does it make if an EGC happens to be run from the load side of the first GFI protected outlet to the 2nd ? even if it cant do it's job.

    Is that not what the GFI was installed for in the first place?

    Also, what normal person is going to go read 250.114 before deciding whether or not they should plug their 3 wire cord into a perfectly accepting 3 wire receptacle ?

    JAP>

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    A GFCI does not need a ground wire in order to detect a ground fault, and break the circuit.

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    Quote Originally Posted by PaulMmn View Post
    A GFCI does not need a ground wire in order to detect a ground fault, and break the circuit.
    Agreed. It does require that the power source has a grounded conductor.
    Code references based on 2005 NEC
    Larry B. Fine
    Master Electrician
    Electrical Contractor
    Richmond, VA

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