Messed up ground, solution?

Discussion in 'General Electronics Chat' started by vladtess, Nov 27, 2013.

  1. vladtess

    Thread Starter Member

    Jan 5, 2011
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    Hello fellas. I have a large building with multiple ground points, some are via copper rods, some are via pipes. However the ground is contaminated: one of the phases is connected to ground so ground (green) wire is always under power (unsafe?). The thing is that I cannot fix it, some rooms are locked so I won't be able to find the source of the problem. Now can I fix it by simply inserting two more rods into surrounding area (and measure resistance) and create a safe ground? Will that create a safe alternative? Thanks much!!!!
     
  2. MikeML

    AAC Fanatic!

    Oct 2, 2009
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    Call the power company. They are obligated to fix screw-ups like this. (At least in the USA).
     
  3. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Need a bit more information? If one of the phases is connected to ground is this to form a neutral as in one corner of a delta system grounded or is it what is euphemistically known as a wild or high leg system to obtain a neutral?
    In what way is one phase connected to earth ground a danger?
    Max.
     
  4. Metalmann

    Active Member

    Dec 8, 2012
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    I doubt if it helps, but every one of my barns/shops; has an individual ground rod.
     
  5. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Or is this a case of a phase being grounded that otherwise is above ground?
    If so it would (should) trip a breaker or blow a fuse if it has a separate grounded neutral?

    A definitive source is SOARES Book on Grounding published by the IAEI (Electrical Inspectors Assoc) Of which the NEC grounding definition is based on.


    This is fairly normal, especially if they have their own service panel.
    Max.
     
    Last edited: Nov 27, 2013
  6. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    Without knowing your location one cannot give a proper/complete answer.
    In the US you should reference article 250 of the National Electrical Code as well as any other applicable sections.
    Also what is meant by the "ground is contaminated" ?

    You also MUST find the building super or whoever can "unlock" these locked rooms.

    Are you even a licensed electrician?
     
  7. #12

    Expert

    Nov 30, 2010
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    Agree!!! This might be a life or death situation. You absolutely must understand the whole circuit or get somebody that does. No guessing allowed!
     
  8. inwo

    Well-Known Member

    Nov 7, 2013
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    Don't mess with a corner grounded delta.

    Find a professional who doesn't have to ask.
     
  9. inwo

    Well-Known Member

    Nov 7, 2013
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    ...............................................................................................
     
  10. MaxHeadRoom

    Expert

    Jul 18, 2013
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    From my experience from working with those on other sites, there are still some UN-orthodox methods used out there, it is not the fault of the person having to operate with the system.
    Max.
     
  11. vladtess

    Thread Starter Member

    Jan 5, 2011
    43
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    Basically when I measure ac voltage between the ground and hot terminal I get 120 volts
     
  12. MaxHeadRoom

    Expert

    Jul 18, 2013
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    In common conditions that is normal?
    The complete configuration would have to be known.
    What is your country/location etc.
    Max.
     
  13. inwo

    Well-Known Member

    Nov 7, 2013
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    True.

    Repairs to an unknown system by an inexperienced person is another story.
     
  14. vladtess

    Thread Starter Member

    Jan 5, 2011
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    We'll I'm not sure about configuration. Just thought that this May not be normal and looking for ways to fix it. I'm in New York.
     
  15. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Then in a normal installation such as in a residential or apartment situation, this is normal.
    Could be nothing to fix?;)
    Max.
     
  16. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    oh boy..
    Just stop now before you kill yourself or someone else.
    If there is any need for electrical inspection/modification in that building you MUST call a licensed electrician.
    This isn't a job for you..
     
  17. inwo

    Well-Known Member

    Nov 7, 2013
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    I rest my case.
     
  18. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Just curious, What was your involvement with this in the first place that gave you a reason for concern?
    Max.
     
  19. GetDeviceInfo

    Senior Member

    Jun 7, 2009
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    your 'phase' wouldn't happen to be colored white would it?
     
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