Results 1 to 5 of 5
  1. #1
    Join Date
    Mar 2012
    Location
    Cleveland, Ohio
    Posts
    51

    Default Grounding in a secondary panel


    The Seller states "his electrician" says this secondary in the 1961 garage is okay and claims it is grounded by the conduit. (What you cannot see is this going to a 220 outlet).
    I argued it required a grounding lock nut as it is a secondary. I thought they should have run a ground wire itself since this is obviously newer installation.

    Thoughts?

    Similar Threads:
    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    F.I.R.E. Services

  2. #2
    Join Date
    Aug 2008
    Location
    Maryland
    Posts
    1,910

    Default Re: Grounding in a secondary panel

    Continuous metallic conduit is a recognized grounding means. No special locknut required.

    - - - Updated - - -

    Continuous metallic conduit is a recognized grounding means. No special locknut required.

    All answers based on unamended National Electrical codes.

  3. #3
    Join Date
    Mar 2007
    Location
    Santa Rosa, CA
    Posts
    2,592

    Default Re: Grounding in a secondary panel

    [QUOTE=Jim Port;280127]Continuous metallic conduit is a recognized grounding means. No special locknut required.

    Yes, but...

    It looks to me like the terminal is isolated from the panel enclosure.

    Chris,

    I share your concern. I often see loose set screw and locknuts. When I see conduit being used as the equipment grounding conductor, I try to notify the client that the conduit fittings can become loose and recommend tightening.

    Department of Redundancy Department
    http://www.FullCircleInspect.com/

  4. #4
    Join Date
    Mar 2009
    Location
    Colorado Front Range
    Posts
    612

    Default Re: Grounding in a secondary panel

    Typically the ground buss would have a green screw that would indicate a connection to the box. The buss would be anchored to the insulating material so that removal of the green screw would allow the buss to be used as an isolated neutral buss.

    Without "my eyes on what's there", impossible to tell if a bonding screw is present in the buss because it isn't required to be green, just usually is.

    The bigger issue is how the receptacle is mounted and hooked up. Done properly, the green wire shown isn't necessary.

    Occam's eraser: The philosophical principle that even the simplest solution is bound to have something wrong with it.

  5. #5
    Join Date
    Feb 2009
    Location
    Southern Vancouver Island
    Posts
    4,592

    Default Re: Grounding in a secondary panel

    You could have checked for continuity between the two lengths of conduit. And conduit to the bus with the green wire.
    If the supply is on a circuit breaker in the main panel, the concern is a good bond to the main panel and that is supplied by the conduit. But as Bill pointed out, we don't know how the green wire connects to the outlet, whether a wire is connected to a grounding screw at the outlet box or not. With your DMM, you could have determined if something was missing there.

    You questioned it and a sparky responded. Job done.

    Last edited by John Kogel; 08-08-2018 at 03:07 PM.
    John Kogel, RHI, BC HI Lic #47455
    www.allsafehome.ca

Bookmarks

Posting Permissions

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