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Thread: panel board as an EGC

  1. #51
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    Quote Originally Posted by macmikeman View Post
    (A) General. Metal raceways, cable trays, cable armor , cable sheath, ENCLOSURES, that are to serve as equipment grounding conductors...............

    The 8 words following enclosures, due overly seem to give permission specifically.
    The issue I have is that 250.118 as written prohibits metal enclosures from being used as an EGC, since they do "enclose the circuit conductors", but are not listed in 250.118. Nothing in 250.96 gives any relief from this 250.118 prohibition. I'm sure the prohibition isn't intentional, so the wording in 250.118 needs to be changed.

    Cheers, Wayne

  2. #52
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    Quote Originally Posted by macmikeman View Post
    I disagree heartedly with this post of yours , so that's like a first for me. (A) General. Metal raceways, cable trays, cable armor , cable sheath, ENCLOSURES, that are to serve as equipment grounding conductors...............

    The 8 words following enclosures, due overly seem to give permission specifically.
    And also when the code doesn't specifically prohibit a practice, then it is implied that the practice is allowed.
    250.96 tells you that a metallic enclosure used as an EGC has to be bonded, but does not actually tell you that it can be used as an EGC.

    Since 250.96 also refers to "other metal non–current-carrying parts that are to serve as equipment grounding conductors". Does that give permission to use any chunk of non-current carrying metal as an EGC?

    250.118 Types of Equipment Grounding Conductors.
    The equipment grounding conductor run with or enclosing
    the circuit conductors shall be one or more or a combination
    of the following
    :
    90.5 Mandatory Rules, Permissive Rules, and Explanatory
    Material.
    (A) Mandatory Rules. Mandatory rules of this Code are
    those that identify actions that are specifically required or
    prohibited and are characterized by the use of the terms
    shall or shall not.
    It seems quite clear that the use of the word "shall" in 250.118 makes the requirement mandatory and not a suggestion.
    Bob

  3. #53
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    Quote Originally Posted by nickelec View Post
    How many panels, cabinets have provisions for multiple egc bars? I have seen some with 2 different possible mounting locations, if you install an EGC bar say with self tappers anywhere wouldn't that voilate the ul listing of that can by not using it the way it was intended?

    Sent from my SM-G950U using Tapatalk
    IMO if you use the bar intended for the cabinet, and the mounting hardware and pre-made holes intended for mounting that bar (some have multiple places within the cabinet where it can be placed), you do not need to remove any paint or worry about if enough mounting screw threads are engaged to make sufficient contact.

    OTOH if you use another manufacturers bar or mount it in your own selected position then you need to remove paint (if a painted enclosure, and possibly can have issues with not enough threads being engaged in the wall of the enclosure. Needs to be two threads engaged, so if you have 8-32 or 10-32 screws it must be 1/16 inch thick to get two threads, other option is long enough screws to put a nut on back side, but that can be difficult if back side is against a mounting surface.

  4. #54
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    Quote Originally Posted by Dennis Alwon View Post
    The code specifically states that the metal of an enclosure cannot be used to connect the neutrals however there is no statement as such for the equipment grounding conductor. I say it is fine.

    If you want use a bonding jumper the size of the largest equipment grounding conductor.
    There is nothing that says that metallic enclosures are EGCs. We have a rule in 314.28(C) that requires a metallic cover to comply with the grounding requirements of 250.110. 250.110 specifically requires that the box cover be connected to an Equipment Grounding Conductor. Without a change to 250.118 telling us that the box is an ECG, you have to connect a bonding jumper to the box cover. Yes, we never install a bonding jumper and we use metallic enclosures as EGCs all the time, but there is nothing in the code that actually permits us to do that.
    Don, Illinois
    The code only applies to T&M work....it does not apply to contract work.

  5. #55
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    Quote Originally Posted by don_resqcapt19 View Post
    There is nothing that says that metallic enclosures are EGCs. We have a rule in 314.28(C) that requires a metallic cover to comply with the grounding requirements of 250.110. 250.110 specifically requires that the box cover be connected to an Equipment Grounding Conductor. Without a change to 250.118 telling us that the box is an ECG, you have to connect a bonding jumper to the box cover. Yes, we never install a bonding jumper and we use metallic enclosures as EGCs all the time, but there is nothing in the code that actually permits us to do that.
    How many junction box covers and conduit body covers have you connected a bonding jumper to? I'm not sure if I ever have on a conduit body, junction box, maybe. Never with a cover on a panelboard cabinet, but occasionally on other hinged cover enclosures, especially if there are devices mounted to the cover (pushbuttons, selector switches, etc.)


  6. #56
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    Quote Originally Posted by kwired View Post
    How many junction box covers and conduit body covers have you connected a bonding jumper to? I'm not sure if I ever have on a conduit body, junction box, maybe. Never with a cover on a panelboard cabinet, but occasionally on other hinged cover enclosures, especially if there are devices mounted to the cover (pushbuttons, selector switches, etc.)

    I have very rarely done that, but I think that the current code wording very clearly requires that.
    Don, Illinois
    The code only applies to T&M work....it does not apply to contract work.

  7. #57
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    Quote Originally Posted by don_resqcapt19 View Post
    I have very rarely done that, but I think that the current code wording very clearly requires that.
    Which one, or all of them?

  8. #58
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    Quote Originally Posted by kwired View Post
    Which one, or all of them?
    All of them.
    Don, Illinois
    The code only applies to T&M work....it does not apply to contract work.

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