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-   -   Low voltage running through yard? (https://www.askmehelpdesk.com/showthread.php?t=490718)

  • Jul 22, 2010, 04:40 AM
    MichGeo
    Low voltage running through yard?
    I have a 700-gallon landscape pond. Kneeling with my knee on the ground, I put my hand in the water and felt an electrical shock in a small cut on my finger. Using a voltage meter with one prong stuck in the earth and the other in the water, it reads around 2 volts when set to AC and .6 volts when set to DC. Thinking it might be a problem with the pump (which is GFCI protected), I flipped the breaker but nothing changed. Thinking it might be a problem with another circuit, I flipped each breaker, and finally the main, but nothing changed. Except for the cut on my finger, I wouldn't have noticed it. Should I be concerned? Or is it normal to have a few volts trickling throug the yard?
  • Jul 22, 2010, 04:56 AM
    Stratmando

    Is your phone line ran under ground? Can you disconnect at 1 end?
  • Jul 22, 2010, 05:11 AM
    MichGeo
    The phone line is underground for the entire street. I can disconnect it where it comes into the house this evening -- I'm not home at the moment.

    Electric and cable TV are overhead on the street, but underground from the pole to the house.
  • Jul 23, 2010, 04:31 AM
    MichGeo

    It was stormy in Michigan last night, so I was not able to disconnect the phone line or check the voltage last evening. I'll try again tonight.
  • Jul 26, 2010, 04:59 AM
    MichGeo

    I disconnected the phone wires entering the house from the box outside. The ground wire from the phone box was dangling in the air so I reattached it to its clip on the house ground wire. The voltage from the pond to the earth did -not- change.

    For fun, I checked the voltage from an outdoor hose bib to a wet concrete patio -- it read nearly 6v AC -- Yikes!
  • Jul 26, 2010, 05:21 AM
    hkstroud

    Suggest checking connections between ground wire and ground rod. Also check connection of ground wire in electric panel.
  • Jul 26, 2010, 06:57 PM
    KISS

    What would be useful is a clamp on ammeter on the water pipe.

    After checking the ground and neutrals in the panel and grounds to plumbing, I think it's wise to call the power company to investigate.

    You could try measuring the voltage from the outside of a cable coax and the screw on an an outlet plate.

    What sometimes happens is the transformer ground is compromised and then what happens is ground is made using the copper pipe. It can actually travel from your neighbor's panel through the water pipe, say if your ground is compromised.

    That's why it's useful to measure the current carried by the water line with a clamp on meter. Should be zero.
  • Jul 26, 2010, 07:18 PM
    Stratmando

    With the Main Off, I would even check the current on the Neutral at the Drip loop.
  • Jul 26, 2010, 08:33 PM
    MichGeo
    Thanks for the suggestions. I will try a couple more things and let you know what I find. We live in a social neighborhood of 1+ acre lots, so I thought it might be interesting to see if my neighbors have similar issues and how far down the street it may be.
  • Jul 27, 2010, 06:42 AM
    Stratmando

    Do your neighbors have underground power?
  • Jul 27, 2010, 11:34 AM
    MichGeo

    Power lines run atop poles down the street, with one pole between each pair of houses. From a given pole, power runs underground to each house. At a given house, the lines come up through a conduit into the meter box.

    For reasons I can't explain, telephone lines and natural gas are underground for the entire street, but electric and cable TV are underground only from the poles to the houses.

    Our load center is mounted to a piece of plywood anchored to a concrete basement wall within a few feet of where the wires come through from the meter.

    (I'm guessing this means I have no drip loops -- though I'm not that savvy with terminology.)

    All water lines are copper, presumably grounded. The house was built in 2003, though we are not the original owners. The basement is completely unfinished and there doesn't look like any remodeling has taken place since it was built.
  • Jul 27, 2010, 12:04 PM
    KISS

    The drip loop may be at the pole. Wires dip when leaving the pole or entering the house. That's the drip loop.
  • Jul 27, 2010, 04:37 PM
    MichGeo

    I turned off the main breaker again (which is darned inconvenient with all the gadgets in the house asking me to reset the time).

    At the pond, I now read only about 2.5vac from the water to the now somewhat dry earth, but I get nearly 9vac from the hose bib to the damp concrete patio.

    With both prongs in the earth I get pretty much nothing, but I get around 5vac from the earth to the house ground wire that goes down into the earth.

    Next door in one direction, there were around 7vac from the hose bib to damp earth. Four house down in the other direction, I was getting around 9vac from the hose bib to very wet earth.

    I say "around" because the numbers fluctuate a few tenths up and down on my inexpensive Craftsman meter.

    Of course, I didn't ask my neighbors to shut off their breakers.

    Sound like a job for the power company?
  • Jul 27, 2010, 05:12 PM
    KISS

    Yup. Measure from cable TV outer connecter to a 120 V outlet ground screw.
  • Jul 27, 2010, 05:42 PM
    MichGeo

    Using only one prong on either the outlet ground or the cable TV connector, the meter fluctuates in the 10ths of a volt between about .5 and .9 (voltage in the air?).

    With one prong on the outlet ground and the other on the cable TV connector, the meter goes to zero.
  • Jul 27, 2010, 07:27 PM
    KISS

    That's good.

    Call the utility.
  • Aug 11, 2010, 01:10 PM
    MichGeo

    A Non-Update: I reported the problem to Consumers Energy on July 29. No response, and the voltage is still out there, so I called back today.

    The rep said that the issue was closed on July 31 with the response that I needed to report it to their AG Services Dept (different phone number). No explanation as to why nobody there thought they should call me to let me know.

    I called the other number, which only accepts messages. Hopefully, they'll call me back. Not sure why agricultural services would be interested in my subdivision.

    Thanks again for the suggestions. I'll post again when I know something more.
  • Aug 11, 2010, 04:56 PM
    Stratmando

    One reason I am on this site is because of Companies So Big, Stupid, and Non Productive, Slow in their response, can't do squat(their job). I thrive on these type of problems. They seem Scared Lazy, or Incompetent.
    Good Luck
    Any measurements taken on the neighbors house?
  • Aug 12, 2010, 06:25 AM
    MichGeo

    Readings from neighboring houses taken while my main breaker was off:

    Next door in one direction, there were around 7vac from the hose bib to damp earth.

    Four house down in the other direction, I was getting around 9vac from the hose bib to very wet earth.

    I say "around" because the numbers fluctuate a few tenths up and down on my inexpensive Craftsman meter.
  • Aug 12, 2010, 06:47 AM
    Stratmando

    Wonder if it would light up a 6 volt bulb, enough Umph behind it?
    Digital Meters are sensitive and can even show voltages not there.

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