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I am new to electricity. I know that if someone is touching one hand one cable of a high voltage cable nothing will happen.

The question is: If there are two cables, each is coming from a different power source, someone is touching one hand in one cable, and the other hand the other cable. What will happen to him?

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Aminadav Glickshtein
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    `I have learned that if I touch with one hand, one cable of a high voltage cable nothing will happen.` ... – pipe Mar 02 '17 at 17:26
  • I knew someone that climbed a tower and touched a wire. The keys in his pocket melted. Steve died instantly. – Misunderstood Mar 02 '17 at 18:00

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OMG .. DO NOT DO EITHER....

It is true, if you are isolated from ground or any other way for current to flow, you can touch a power line without frying yourself. However, in order to get up to that voltage you need to be "charged up" first. That can also kill you if the voltage is high enough.

However touching another cable at the same time from a different source can also fry you if the source is at a different potential or a different phase from the first.

Since you can never be sure of either of those... DO NOT EVEN THINK ABOUT IT.

Even touching the same cable at different points, say arms outreached can kill you, especially with a.c. cables. The voltage will be different in each hand.

HOWEVER If you are talking about HIGH voltages, you may think you are isolated, when in fact you are actually not. If you are close enough to a conductive "drain" the energy can pass through you then JUMP through the air to said drain and you will have a very BAD day.

R.I.P. the man in your image.

Trevor_G
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    There is also the matter of voltage equalization. See https://www.youtube.com/watch?v=x94BH9TUiHM and note the arc being drawn at about 00:45, as the helicopter voltage is brought up to the line voltage. – WhatRoughBeast Mar 02 '17 at 18:19
  • This guy has an interesting take as to why birds don't get zapped by their own capacitance: http://electronics.stackexchange.com/questions/158778/can-a-bird-previously-at-earth-potential-get-electrocuted-by-landing-on-a-powe – bobflux Mar 02 '17 at 18:56
  • @WhatRoughBeast Cool video. An interesting ride to be sure. – DoxyLover Mar 02 '17 at 19:05
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Voltage does not harm you, no matter how high... it's the current that gets you.

Burns need lots of current. Cardiac arrest needs very little. For extra comic relief, when you're on top of a very high ladder, a tiny jolt might be enough to send you flying. You can do all three at home if you're not careful, low voltage mains is already enough.

High voltages have a way to turn what you think is an insulator into something conductive enough to zap you. For example, rubber gloves work up to a certain (low) voltage, but above that, any pinhole in the material will let an arc through. As for air, it insulates... up to when it doesn't.

But IMO the best is 1000µF charged to 2kV, as found in audiophile tube amps.

TL/DR: only sit on a high voltage line if you're a sparrow.

bobflux
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