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Thread: 250.68 (C) (2)

  1. #1
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    250.68 (C) (2)

    I'm a little confused about when you can use building steel as a GEC. I have a steel conex sitting on timbers on the ground. I do not have a separately derived system in the conex but I do have a panel with an EGC in the feeder. Can I run a GEC from the panel to a beam inside the conex and then attach a GEC to the outside steel framing of the conex to bond the conex to an electrode or does the GEC need to be continuous?

  2. #2
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    Back up and look at 250.52. Does the steel in your steel conex sitting on timbers qualify as a grounding electrode?
    If you go and decide to dance with a gorilla the dance ain't over till the gorilla decides it's over.

  3. #3
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    Quote Originally Posted by ActionDave View Post
    Back up and look at 250.52. Does the steel in your steel conex sitting on timbers qualify as a grounding electrode?
    No it doesn't but I'm not using it as an electrode. I'm using the building steel as a GEC. My GEC (#2 copper wire) from the panel is not continuous to the grounding electrode. I'm attaching the GEC from the panel to the steel inside then attaching a GEC outside to an approved grounding electrode. I'm asking if the code intends the GEC to be continuous from the panel to the electrode or can I use the building steel as part of the path to the electrode?

  4. #4
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    Quote Originally Posted by AKsparky1 View Post
    No it doesn't but I'm not using it as an electrode. I'm using the building steel as a GEC. My GEC (#2 copper wire) from the panel is not continuous to the grounding electrode. I'm attaching the GEC from the panel to the steel inside then attaching a GEC outside to an approved grounding electrode. I'm asking if the code intends the GEC to be continuous from the panel to the electrode or can I use the building steel as part of the path to the electrode?
    Good luck with that.
    If you go and decide to dance with a gorilla the dance ain't over till the gorilla decides it's over.

  5. #5
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    It seems that drilling a single 1/4" hole for the GEC would easier than bolting two lugs to the container box. Bolting the panel itself to the container should suffice for bonding it.
    Code references based on 2005 NEC
    Larry B. Fine
    Master Electrician
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    Richmond, VA

  6. #6
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    It would take me as much time to run 8ft of GEC as it would to look this up in the code for a definitive answer.

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    Quote Originally Posted by jaggedben View Post
    It would take me as much time to run 8ft of GEC as it would to look this up in the code for a definitive answer.
    Yes it would however it is already done this way. It appears by reading 250.68 (C) (2) and by reviewing Mike Holts code change DVD that when attatching to a beam and the hold down bolts are tied to an electrode that the building steel can be used as a Grounding Electrode Conductor. This conex has a electrode attached to it via bolted connection.

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    Quote Originally Posted by AKsparky1 View Post
    Yes it would however it is already done this way. It appears by reading 250.68 (C) (2) and by reviewing Mike Holts code change DVD that when attatching to a beam and the hold down bolts are tied to an electrode that the building steel can be used as a Grounding Electrode Conductor. This conex has a electrode attached to it via bolted connection.
    True, but only if the building steel qualifies as a grounding electrode. Your building steel is sitting on timbers - not a qualifying electrode.

    You were told in post 2 to go to 250.52 and see if your building steel is a qualifying electrode - which you seem to wish to ignore the fact that it isn't.

    From 250.52:

    (2) Metal Frame of the Building or Structure.
    The metal frame of the building or structure that is connected to the earth by one or more of the following methods:


    At least one structural metal member that is in direct contact with the earth for 3.0 m (10 ft) or more, with or without concrete encasement.


    Hold-down bolts securing the structural steel column that are connected to a concrete-encased electrode that complies with 250.52(A)(3) and is located in the support footing or foundation. The hold-down bolts shall be connected to the concrete-encased electrode by welding, exothermic welding, the usual steel tie wires, or other approved means
    Again sitting on timbers doesn't make your steel structure a qualifying electrode.
    I live for today, I'm just a day behind.

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    Similar Situation Piggyback Question

    I have a HAZMAT container sitting on concrete 3' from the building that feeds its panel board for lighting and fan power . The panel board has a 4 wire feeder from the building next to it with EGC installed. Can I run the GEC to the building steel even though it is not the "building or structure being served" per 250.50 or do I need to add its own grounding electrode?

  10. #10
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    Quote Originally Posted by czarjam View Post
    I have a HAZMAT container sitting on concrete 3' from the building that feeds its panel board for lighting and fan power . The panel board has a 4 wire feeder from the building next to it with EGC installed. Can I run the GEC to the building steel even though it is not the "building or structure being served" per 250.50 or do I need to add its own grounding electrode?
    I tried to move this but please start a new post. Tom
    Moderator-Washington State
    Ancora Imparo

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