Page 2 of 7 FirstFirst 1234 ... LastLast
Results 11 to 20 of 65

Thread: Grounding electrode 250.64(D)

  1. #11
    Join Date
    Jan 2007
    Posts
    2,903
    Quote Originally Posted by nickelec View Post
    The two greens going.to each panel are bonding jumpers from the neutral bar

    Sent from my SM-G950U using Tapatalk
    ???

    JAP>

  2. #12
    Join Date
    Feb 2003
    Location
    Minnesota
    Posts
    6,519
    Quote Originally Posted by nickelec View Post
    Can you do this?

    we usually use one of these if there is more then one panel
    It looks like you have a bare stranded #4 heading off in the EMT. It looks like the #4 is the grounding electrode conductor.

    It also looks like you have a green #6 going down out of photo which I assume is going to a supplemental grounding electrode.

    The problem with this assembly is coming from the rule 2017 NEC 250.64(C). Lugs are not allowed to splice the grounding electrode conductor.

    It looks like you have two green #6 coming out of what I assume are two 100 A service disconnects. If those two green #6 were irreversibly spliced by means in the rule 250.64(C) to somewhere on the length of the #4 then that would work for the #4 to land on the lug attached to copper bar, and the grounding electrode conductor would be continuous into the service disconnects.
    Another Al in Minnesota

  3. #13
    Join Date
    Dec 2012
    Location
    Placerville, CA, USA
    Posts
    18,374
    Or, to look at it another way, you cannot have your ground to neutral bond on a bus bar outside the several panels and call the wire(s) back to the panels bonding jumpers. The bond can occur at a meter, or at a service disconnect. Not out in free space.

  4. #14
    Join Date
    Jan 2007
    Posts
    2,903
    Quote Originally Posted by GoldDigger View Post
    Or, to look at it another way, you cannot have your ground to neutral bond on a bus bar outside the several panels and call the wire(s) back to the panels bonding jumpers. The bond can occur at a meter, or at a service disconnect. Not out in free space.



    And if those 2 green conductors are actually coming from the insulated neutral bars in those 2 load centers, or directly from the ground bar only, and those 2 loadcenters have main breakers and are actually serving as the service disconnects, and that's where they meant to bond, then there is actually no bond at all inside those 2 panels if the actual bonding screw that is supposed to be used for the bonding jumper was not installed.

    whewwwww......

    JAP>

  5. #15
    Join Date
    Jan 2007
    Posts
    2,903
    If a fault current returned on the branch circuit EGC's to the ground bar bolted to the panel tub, there would be no way for the fault to clear if the bonding jumper is not actually installed between the ground bar and the insulated neutral bar, which would in turn, energize all normally non current carrying parts of the system, leaving a potential for an electrical arc or for some unsuspecting person to come along and create a path to get their butts knocked off.

    JAP>

  6. #16
    Join Date
    Dec 2006
    Location
    Chapel Hill, NC
    Posts
    32,347
    I don't see an issue with this

    A grounding electrode conductor tap shall extend to the
    inside of each disconnecting means enclosure. The grounding
    electrode conductor taps shall be sized in accordance
    with 250.66 for the largest service-entrance or feeder conductor
    serving the individual enclosure. The tap conductors
    shall be connected to the common grounding electrode conductor
    by one of the following methods in such a manner
    that the common grounding electrode conductor remains
    without a splice or joint:
    (1) Exothermic welding.
    (2) Connectors listed as grounding and bonding equipment.
    (3) Connections to an aluminum or copper busbar not less
    than 6 mm thick × 50 mm wide (1⁄4 in. thick × 2 in. wide)
    and of sufficient length to accommodate the number of
    terminations necessary for the installation. The busbar
    shall be securely fastened and shall be installed in an
    accessible location. Connections shall be made by a listed
    connector or by the exothermic welding process. If aluminum
    busbars are used, the installation shall comply with
    250.64(A).
    They say I shot a man named Gray and took his wife to Italy
    She inherited a million bucks and when she died it came to me
    I can't help it if I'm lucky



  7. #17
    Join Date
    Jan 2007
    Posts
    2,903
    Quote Originally Posted by Dennis Alwon View Post
    I don't see an issue with this
    The issue I see is he called the 2 green wires "Bonding Jumpers" in post #10.

    That cannot be the case in this picture.

    JAP>

  8. #18
    Join Date
    Jan 2007
    Posts
    2,903
    Maybe it's not the MBJ,,, I don't know.

    JAP>

  9. #19
    Join Date
    Mar 2008
    Location
    Michigan. It's a beautiful penninsula, I've looked around.
    Posts
    9,429
    Quote Originally Posted by Dennis Alwon View Post
    I don't see an issue with this
    The tap conductors
    shall be connected to the common grounding electrode conductor
    by one of the following methods in such a manner
    that the common grounding electrode conductor remains
    without a splice or joint:



    Am I reading too much into that?
    Cheers and Stay Safe,

    Marky the Sparky

  10. #20
    Join Date
    Jan 2007
    Posts
    2,903
    To me, as long as they are not considering the 2 green wires coming out of the 2 panels as the the "Main" Bonding Jumpers for those 2 panels, the picture pretty well is to a Tee what that paragraph just explained.

    If the bare conductor in the picture is the "Main common grounding conductor" and it is not spliced anywhere between where it terminates at the bussbar and whatever Grounding Electrode it's attached to at the other end, I can't see a problem with it at all.

    It just says, that portion between the bussbar and the electrode on the other end must not have a splice in it in my opinion.

    JAP>

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •