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Q & A: dangerous ideas about electricity

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Most recent answer: 07/19/2016
Q:
Situation:Plugged in Electric Lamp with Switch in Off (open) position � light bulb is not on. Question to Electrician:Even with switch off (open position), is there a minor electrical flow � is the flow sufficient that, if you put your tongue on the pole, you could feel the flow?Electrician�s answer:Don�t try it, something might be wired wrong, but YES, because of electron motion/movement there would be a minor flow that you could possible feel with your tongue.My Question:Was the electrician correct � there is still a minor electrical flow even with switch off (open position)?If Yes, is the electrical flow AC or DC?If it is DC, which pole (Negative or Positive) would you have to touch to feel it?If it is DC, would it be a one-time charge that would dissipate like static build-up between carpet & leather soled shoes?
- Leonard Kamman (age 80)
Kingwood, Texass
A:

One reason that the electrician is right about the danger is that circuits are frequently mis-wired so that the switch is in the neutral line rather than the hot line. That means you can get electrocuted messing with an "off" device. In two houses  that I've been responsible for, there were at least 4 (I think 5) cases of this mis-wiring. I had at least two close calls working on things that were supposed to be off. My neighbor just asked two days ago about a light that was flickering when it was supposed to be off- a sign that he has mis-wiring too. 

As for dc voltages, those show up all the time from rubbing shoes on the floor, etc. The danger here is from the ac.

Mike W.


(published on 07/19/2016)

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