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Medical Voltmeter registers on my skin

  1. Oct 20, 2012 #1
    Can anyone out there tell me why a voltmeter would strongly register when I touch it to my arm, and yet I am in no contact with any electrical current? This seems outrageous to me. It is a commercially available pen tester bought at Home Depot and set on the highest setting.
  2. jcsd
  3. Oct 21, 2012 #2
    I'm not really sure what you are talking about, you should be getting almost no volts or amps if u are touching it to your arm. Maybe you have it set on ohms? I imagine that would get a pretty strong reading, especially if you held on lead in one hand and one lead in the other.
  4. Oct 21, 2012 #3
    I am touching nothing, the voltmeter is set for household use, and the other hand is free. Any ideas?
  5. Oct 21, 2012 #4
    it is not set to ohms, it is really nuts.
  6. Oct 21, 2012 #5
    if you are in So Cal, I would be glad to meet up with you and demonstrate this nutty phenom.
  7. Oct 21, 2012 #6
    Voltage is measured between two points. One point is touching your arm, but what is the other point?

    Or they do make non-contact voltmeters that, if I understand correctly, treat the surface you're measuring as one plate in a capacitor and the meter probe as the other plate and measure the charge across the plates. In that case, your arm might simply have a charge on it that the meter is measuring. I don't really know the details of these devices, but your pen might've come with a manual that tells you how it works.
  8. Oct 22, 2012 #7
    I agree, I am supposed to touch a conductive plate around the electrical device, but i don't have to do that, all I am doing is standing (I've tried this in many rooms and outdoors) and if I make contact with any part of my skin on my arm or face the volt alarm sounds at its highest sound.
  9. Oct 24, 2012 #8
    Can you link to an Ad for the meter?
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