Where does the electricity go

Discussion in 'General Electronics Chat' started by justplumducky, Mar 22, 2010.

  1. justplumducky

    Thread Starter New Member

    Mar 22, 2010
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    For an experiment, I connected a wire to the hot side of a 120vac outlet and then connected the other side to the shaft of a screwdriver which I stuck into the the ground (with a voltmeter in between the screwdriver and outlet). The 120 volt level of the meter lit up, so I assume there was current flow.

    It' my understanding that electricity requires a complete path/circuit for continuous flow (according to the first paragraph of the following article: http://www.allaboutcircuits.com/vol_1/chpt_3/3.html, ) so my question is:

    Where does the electricity go after it leaves the screwdriver? Please identify the rest of the complete path.

    Thx much for any help.
     
  2. Wendy

    Moderator

    Mar 24, 2008
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    There is also capacitance. The neon bulb requires extremely low current flows to ionize the gas (extremely low is an understatement). It wouldn't do this with DC, though it would flash as the probe charges up.

    It is closely linked to static electricity.
     
  3. retched

    AAC Fanatic!

    Dec 5, 2009
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    DOnt- EVER - do that again -

    There was current flow, and it was enough to kill you.

    It went from hot to ground. In your breaker box, you will see that neutral and ground are typically wired together.

    You could have just used the meter probes and skipped the screwdriver
     
  4. beenthere

    Retired Moderator

    Apr 20, 2004
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    Household power is referenced to earth ground. Your distribution panel has a direct connection to earth. Your screwdriver was a low grade short.

    What was your experiment meant to demonstrate? Experimenting with the power outlets is very unsafe.
     
  5. BillB3857

    Senior Member

    Feb 28, 2009
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    You need to change your nickname to justplumLUCKY. Messing around with exposed 120VAC is not something encouraged for obvious reasons to the initiated but not so obvious, apparently, to the non-initiated.
     
  6. retched

    AAC Fanatic!

    Dec 5, 2009
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    I was thinking the EXACT same thing when i read the OPs post. :)
     
  7. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    What if he uses pliers next time?:eek:

    To the O/P or anyone else, this was a joke!!!!
     
  8. SgtWookie

    Expert

    Jul 17, 2007
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    Bad joke, shortbus.

    When I was a very young boy, I tried an experiment with mains power that just by pure dumb luck didn't kill me.

    It was the first of many experiments that by the grace of my pure dumb luck and my Guardian Angel didn't flat kill me outright.

    I've had a really, really wonderful Guardian Angel so far. I'm very thankful for her efforts, and am doing my best to give her a break. I haven't seen her, but I'm sure I've given her plenty of gray hair.

    Try to keep your Guardian Angel young. Don't tempt fate by playing with mains power.
     
  9. spinnaker

    AAC Fanatic!

    Oct 29, 2009
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    Yeah and then there was my "worm getter" that ran off of 120 VAC.

    Amazing we all survived those years. :)
     
  10. beenthere

    Retired Moderator

    Apr 20, 2004
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    Okay, point made. Electricity is not to be played with in ignorance.
     
  11. Externet

    AAC Fanatic!

    Nov 29, 2005
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    Hot120V------------meter--------screwdrivershaft----------soil

    The current will flow along the line above. The electric power company has one of the electricity supply wires, the neutral, usually connected to the soil.

    Then,

    Hot120V----------------------------outlet hot
    Groundedneutral--------------------outlet neutral

    Were as you see, neutral can also be soil.

    So both ends of the first sketch above correspond to the "plus" and the "minus"
    The very high resistance of the indicator meter in the path of current does not allow the current to make a melting spark by limiting it greatly.
     
  12. justplumducky

    Thread Starter New Member

    Mar 22, 2010
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    Well, I just spent quite a while with a reply apologizing to those who misunderstood my experience level, as well as spending time explaining my question more, and I just lost it all (my reply I mean). I also momentarily "lost it" when I lost the reply I spent so much time on... I lost the reply because I spent too much time on it and was logged out, so when tried to send it, I couldn't go back and recover that screen. Anyway, thx for all the admonitions - good to know you're all looking out for the truly inexperienced. I can safely handle it, however.

    Externet, thank you - you have hit on what I'm really after. I easily understand the first linear illustration (sketch), but I'm not sure I about the rest, so I need to elaborate on my question for you (or anyone else, obviously). I think, with your second linear sketch, you are confirming what I believe is the "rest of the path/circuit" I mentioned in my original question, but I'm not sure.

    First I want to reiterate that, according to that article in the link I posted (my initial post), the current returns to the neutral side of any given circuit (when there is continuous flow, as opposed to momentary discharge and dissipation into an earth ground or relative ground, as a result of static electricity discharge). In other words, it has to return to its source, via a complete circuit (the "rest of the path/circuit" I mentioned previously). Correct? And the following pic will illustrate my question (and where it originated from).

    [​IMG]

    Source of the pic is http://thecircuitdetective.com

    This pic is illustrating the path of short-to-ground current, but if I understand it all correctly, it doesn't matter whether I'm asking about the path of short-to-ground current or normal current from appliances or whatever, it all goes back to the source (stepdown transformer at the power co.'s pole). In the case of a normally operating (energized) appliance circuit, current goes back from the load/appliance to the neutral bus bar in the service panel, then on back to the transformer via the neutral wire that's connected between the neutral bus bar and the transformer. Is that all correct? Sorry to elaborate so much, but it helps to present it in my own words, then ask for confirmation (or not).

    Then if that's all correct, the current leaving my screwdriver would find its way back to the transformer (the source) either by returning to my service panel via my ground rod outside, then to the neutral bus bar in the panel (if they're both connected),and then on back to the transformer via the neutral wire between neutral bus bar and transformer. Or, if grounded neutral near the transformer pole is closer to my screwdriver than my sytem's ground rod, current from the screwdriver would take the path of least resistance and go straight to the pole's gounded neutral, then to transformer. Correct?
     
    Last edited: Mar 23, 2010
  13. Externet

    AAC Fanatic!

    Nov 29, 2005
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    Seems you did grab the correct idea of the current path.

    In other way to put the sketch,


    Hot120V---meter---screwdrivershaft---soil---soil resistance---ground rod---neutral

    Where both ends are the connection to the power company pole transformer secondary.
     
  14. justplumducky

    Thread Starter New Member

    Mar 22, 2010
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    "transformer secondary" as in transformer primary windings (the higher voltage side of a stepdown transformer) and secondary windings (the house side)?
     
  15. Externet

    AAC Fanatic!

    Nov 29, 2005
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    Yes. The power company distributes ~13KV for long runs (the uppermust wires at the poles) and every certain number of houses feed a transformer primary.
    The secondary of those transformers on the poles feed the houses.
    If you carefully look/follow at the wires on a pole you will see what is what and where they hook up to.
     
  16. justplumducky

    Thread Starter New Member

    Mar 22, 2010
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    I most certainly will do that. Can't thank you enough!
     
  17. justplumducky

    Thread Starter New Member

    Mar 22, 2010
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    Wow! I just discovered all your posts....and the variety. Incredible. No reply requested - thx again.
     
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