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Thread: rods on rock

  1. #1

    Question rods on rock

    if i drove a ground rod vertically and hit solid rock,then pulled it back out and drove it at 45 degree angle and hit rock so that 1 foot still is above grade,could i bent top 1 foot over and cover it with dirt or would i have to lay rods horizontally 30" below grade?

  2. #2
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    what is the lenght driven??
    Charlie

  3. #3
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    Quote Originally Posted by tommyrice View Post
    if i drove a ground rod vertically and hit solid rock,then pulled it back out and drove it at 45 degree angle and hit rock so that 1 foot still is above grade,could i bent top 1 foot over and cover it with dirt or would i have to lay rods horizontally 30" below grade?
    8' is required to be below grade but I won't tell you that I have never cut a ground rod before in that situation. :grin:

  4. #4
    Quote Originally Posted by tommyrice View Post
    if i drove a ground rod vertically and hit solid rock,then pulled it back out and drove it at 45 degree angle and hit rock so that 1 foot still is above grade,could i bent top 1 foot over and cover it with dirt or would i have to lay rods horizontally 30" below grade?
    I've beenin this situation, and the code proper way to do it is dig down 24", and bend it over horizontally. If you do this right at, or barely below grade, you will most likely not pass. I've tried it

  5. #5
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    The requirement is that you install the rod vertically 8' deep at an angle not greater than 45°. If this is not possible due to rock then you can bury the entire rod horizontally. I see no wording that would permit you to bend over and bury just the top portion of the rod.

    250.53(G) Rod and Pipe Electrodes. The electrode shall be installed such that at least 2.44 m (8 ft) of length is in contact with the soil. It shall be driven to a depth of not less than 2.44 m (8 ft) except that, where rock bottom is encountered, the electrode shall be driven at an oblique angle not to exceed 45 degrees from the vertical or, where rock bottom is encountered at an angle up to 45 degrees, the electrode shall be permitted to be buried in a trench that is at least 750 mm (30 in.) deep. The upper end of the electrode shall be flush with or below ground level unless the aboveground end and the grounding electrode conductor attachment are protected against physical damage as specified in 250.10
    Rob

    Chief Moderator

    All responses based on the 2011 NEC unless otherwise noted

  6. #6
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    Quote Originally Posted by Dennis Alwon View Post
    I won't tell you that I have never cut a ground rod before in that situation. :grin:
    Your cutting off the manufactures stamp, easy bust for the EI.

  7. #7
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    Quote Originally Posted by chris kennedy View Post
    Your cutting off the manufactures stamp, easy bust for the EI.

    Do all rods have those? Since 5/8" rods aren't required to be listed do they have stamps?
    Rob

    Chief Moderator

    All responses based on the 2011 NEC unless otherwise noted

  8. #8
    Quote Originally Posted by infinity View Post
    The requirement is that you install the rod vertically 8' deep at an angle not greater than 45°. If this is not possible due to rock then you can bury the entire rod horizontally. I see no wording that would permit you to bend over and bury just the top portion of the rod.
    I was taught the way I posted above, after rereading, that's probably not correct. I see what you mean about the enire rod part, I never realized it said that.

  9. #9
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    Quote Originally Posted by infinity View Post
    Do all rods have those? Since 5/8" rods aren't required to be listed do they have stamps?
    I couldn't tell you. I use 5/8 and 3/4 copper clad here as per specs and both are stamped. Anyone got a 5/8 galvie on the truck they could take a quick look at?

  10. #10
    Join Date
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    Quote Originally Posted by infinity View Post
    The requirement is that you install the rod vertically 8' deep at an angle not greater than 45°. If this is not possible due to rock then you can bury the entire rod horizontally. I see no wording that would permit you to bend over and bury just the top portion of the rod.
    I agree with the lack of specific wording, but I think it would be silly to not allow it. The whole rod would conform to one of the ways that are permissible.
    Everything I say is fully substantiated by my own opinion

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