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If a wire in a high voltage circuit is exposed and you touch it will you get a shock?

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gonadgranny

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Quick and easy question here. If a wire in a high voltage circuit is exposed and you touch it will you get a shock? now I know that is you touch a wire which is not grounded you will but if it is still grounded only the wire is exposed will the electricity carry on down the wire(less resistance) or is there a chance that it might go through you? apologies if this is a hopelessly obvious question. Thanks.
 

To get a LETHAL shock, a current of greater then 30mA must flow through your body. So if you touch a wire with a high voltage on it your body now has a high voltage on it. If some other part of your body has a resistance to earth, such that the 30 mA can flow through your body, then you will get a lethal shock, if the resistance is very high to ground such that the current is less then 1mA you will get a bad tingle. When maintenance work is done on the high voltage grid (132KV), the men are working from a box actually suspended from the live wires, but there is no earth anywhere, so there is no current to earth.
Frank
 

It really depends on the voltage and the conditions. I guarantee an extreme shock from modern ignition systems even when you think there is no apparent ground or complete circuit. The frequency of the voltage would have an effect as well.
Radio Frequency power would jump through clothes and even substantial distances to complete the circuit. Even Ham radio linears have interlocks on the covers to help protect people from that hazard.
 

When you touch any object, it creates an opportunity for free electrons to transfer, in order to equalize the electrical charges between you and the object. If the voltage differential is high enough, and the current is high enough, then you'll feel a brief shock. You don't have to be grounded.

Suppose a wire is carrying continuous current? I'm pretty sure there is a threshold of voltage (several hundred volts, maybe), when humidity in the air, and your body capacitance, will dissipate free electrons away from you, with no connection to ground. In those conditions you'll feel a continuous shock when you touch the wire. (I could be wrong.)

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Here is an eye-popping video of a lineman working on power lines carrying half a million volts. The juice is not shut off.

As the helicopter carries him right up close, he holds a metal rod toward the wires, drawing sparks several feet long. I believe the purpose is to bring the helicopter to the same electrical potential as the wires.

Finally he steps onto the wires. A 'Faraday suit' is the only thing protecting him from lethal shock.

https://www.youtube.com/watch?v=9tzga6qAaBA
 

When you touch any object, it creates an opportunity for free electrons to transfer, in order to equalize the electrical charges between you and the object. If the voltage differential is high enough, and the current is high enough, then you'll feel a brief shock. You don't have to be grounded.

Suppose a wire is carrying continuous current? I'm pretty sure there is a threshold of voltage (several hundred volts, maybe), when humidity in the air, and your body capacitance, will dissipate free electrons away from you, with no connection to ground. In those conditions you'll feel a continuous shock when you touch the wire. (I could be wrong.)
You are correct. 750 volts from electro-static discharge is the minimum threshold to sense the spark.. Even though the spark might be impressive it is low amperage. That's why ESD damages IC's, transistors, the maximum voltage ratings are exceeded and insulation of the metaloxide layers are perforated and the failure process has begun.
I think the human body is between 15 pf and 50 pf.
 
Cool video and very informative reply's. Thanks very much for the help.
 

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