Voltage on my kitchen sink

Discussion in 'General Electronics Chat' started by SoulCrank, Oct 11, 2016.

  1. SoulCrank

    Thread Starter New Member

    Oct 11, 2016
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    I was checking the outlet above my counter top and it was 122.3 vAC hot to neutral. Just for fun I put the negitive meter lead on my stainless steel sink and it read 20.7 vAC.
    Is this because it is gronding through the water? Why only 20 v? It has plastic water supply lines and pvc drain.
     
  2. BR-549

    Well-Known Member

    Sep 22, 2013
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    It might be crud built up on the inside of drain pipe giving you a path.

    You might want to check the conductivity of your water also.

    If it was metal plumbing, you should have close to the line voltage between the hot lead to sink.

    What was the voltage from hot to ground on outlet?
     
  3. SoulCrank

    Thread Starter New Member

    Oct 11, 2016
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    about .4 to 1.1 flluctuating.
     
  4. SoulCrank

    Thread Starter New Member

    Oct 11, 2016
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    Sorry I read that wrong. Its about 123.5
     
  5. BR-549

    Well-Known Member

    Sep 22, 2013
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    Adjust a small continuous stream of water. Be very careful........measure between hot lead and water.

    And sink and hot lead while water running.

    Might consider ground fault outlet.
     
  6. floomdoggle

    Senior Member

    Sep 1, 2008
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    Do you have copper pipes? You may have the old style grounding to the pipes, usually at the water heater is the connection. While not specifically dangerous, as there is little current draw, a licensed electrician should be your next step.
     
  7. wayneh

    Expert

    Sep 9, 2010
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    If you have an outlet close enough to your sink that you can reach both with your meter leads, you need it protected with a GFCI!
     
    MaxHeadRoom and shortbus like this.
  8. aidayley

    Member

    Jul 26, 2016
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    My guess would be that you a little bit of crud which is holding water and some were in the line it comes in contact with earth (metal pipe underground) and it eventually gets to your grounding rods and I'm sure there is a fair amount of resistance causing that drop in voltage.
    See if there is a difference after you get rain

    AIDayley
     
  9. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Also an influence is the high impedance of a electronic VOM. Similar to the neon screwdriver that lights when using ones body as a conductor to earth.
    Max.
    [​IMG]
     
  10. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    Fluorescent light over the sink? They can easily cause a high impedance meter to show voltage..

    But I'm probably going with a high resistance path to ground there through water/moist crud..
     
  11. wayneh

    Expert

    Sep 9, 2010
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    I was going to mention that the experiment should be repeated with a high ohms resistor, 100K or 1MΩ for instance, connecting the sink to the ground pin. The tiny current might make the measured voltage disappear. It's just a ghost.
     
  12. SoulCrank

    Thread Starter New Member

    Oct 11, 2016
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    OK, some things going on. I remeasured everything this morning. 122.0 v hot to n. and hot to g. no dif. ov grd to n. 13.0 v max hot to water flow. Still 20 v on sink while water running. this is a ground fault outlet.
    I measured again while dishwasher running. 12.0 v hot to sink, 8 v hot to water, outlet readings were same as above.
     
  13. SoulCrank

    Thread Starter New Member

    Oct 11, 2016
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    Dishwasher and outlet measured are on different breakers.
     
  14. BR-549

    Well-Known Member

    Sep 22, 2013
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    Roger on the ground fault outlet. You can track the path down if you want. The resistance between the sink and all structures touching the sink. Then the resistance of the hot water leg, cold water leg and then the drain leg. I believe you said the plumbing was plastic.

    Just curious....what kind of soil are you on and are you on a municipal supply or well? Are you on an old sewer system?
     
    aidayley likes this.
  15. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    So you have plastic water pipes to your sink and you measure the stainless steel faucet. What do you expect to be the cause, what happens when you set the meter to current (amps) and measure again, does it blow the fuse in the meter or show a few microAmps of current?
     
  16. aidayley

    Member

    Jul 26, 2016
    34
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    Another possibility is that it is going though your counter top then though a grounded appliance
    Could you also check sink to ground

    AIDayley
     
  17. wayneh

    Expert

    Sep 9, 2010
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    I have to reiterate: A voltage measured without a load is a virtually useless number. If the voltage, say 20V, collapses under the load of a 100K or 1MΩ resistor, it's completely meaningless. So far that's all we've seen?
     
  18. SoulCrank

    Thread Starter New Member

    Oct 11, 2016
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    It apears to be clayish soil. City water supply, and prob. a very old sewer sytem.

    But every thing has changed again. Now I have 102.0 vac hot to sink, 1.3 v gnd to sink 1.2v neu to sink. 117.5v hot to neu.
     
  19. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Well, you have just demonstrated that your high impedance meter works like a high impedance meter.

    If your sink was in the circuit with the mains power, the sum of the hot-to-sink plus neutral-to-sink would have equaled the hot-to-neutral.

    Please measure AMPs from sink to ground. Do you get anything? Likely no.
     
  20. wayneh

    Expert

    Sep 9, 2010
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    Still useless!
     
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