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Got shocked by 120VAC
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SteveyG:

--- Quote from: GlennSprigg on June 11, 2021, 11:38:15 am ---Well... The 2nd sentence, above, that I put in Bold, IS true!!, though the rest is crap...
It IS the 'Current' that kills!!!

--- End quote ---

It's not though, since it's not a single factor. It's most reliable to say that exceeding a specific amount of energy is what can stop the heart - There are factors in both power and time. The human body could survive kiloamperes of current if the duration is short enough.


--- Quote from: GlennSprigg on June 11, 2021, 12:51:17 pm ---Now grab hold of a 50-100 thousand volt Van-De-Graph
generator which has no ability to supply the 'current' necessary to be dangerous, then you can laugh at the sparks!!
--- End quote ---

Are you saying that somehow a Van de Graaff generator is somehow able to alter the laws of physics by somehow conducting only a tiny amount of current through a person despite a high voltage being present across them?
Zero999:

--- Quote from: SteveyG on June 11, 2021, 01:09:23 pm ---
--- Quote from: GlennSprigg on June 11, 2021, 11:38:15 am ---Well... The 2nd sentence, above, that I put in Bold, IS true!!, though the rest is crap...
It IS the 'Current' that kills!!!

--- End quote ---

It's not though, since it's not a single factor. It's most reliable to say that exceeding a specific amount of energy is what can stop the heart - There are factors in both power and time. The human body could survive kiloamperes of current if the duration is short enough.


--- Quote from: GlennSprigg on June 11, 2021, 12:51:17 pm ---Now grab hold of a 50-100 thousand volt Van-De-Graph
generator which has no ability to supply the 'current' necessary to be dangerous, then you can laugh at the sparks!!
--- End quote ---

Are you saying that somehow a Van de Graaff generator is somehow able to alter the laws of physics by somehow conducting only a tiny amount of current through a person despite a high voltage being present across them?

--- End quote ---
A  Van de Graaff generator is a constant current source of a few µA. It outputs the same current, regardless of the open circuit voltage, up to a point, when the voltage is so high, it arcs over. If you put one hand on the dome and the other on the earthed side and turn it on, the open circuit voltage will be tiny and the current too low to shock. If you allow the dome to charge, the voltage will increase. If you discharge the dome into your finger, you'll get a shock, but it won't be dangerous, because the dome has too little capacitance, to store enough energy to be hazardous. If you connect it to a large capacitor and leave it running, it can deliver a lethal shock.
SteveyG:

--- Quote from: Zero999 on June 11, 2021, 01:44:54 pm ---A  Van de Graaff generator is a constant current source of a few µA. It outputs the same current, regardless of the open circuit voltage, up to a point, when the voltage is so high, it arcs over. If you put one hand on the dome and the other on the earthed side and turn it on, the open circuit voltage will be tiny and the current too low to shock. If you allow the dome to charge, the voltage will increase. If you discharge the dome into your finger, you'll get a shock, but it won't be dangerous, because the dome has too little capacitance, to store enough energy to be hazardous. If you connect it to a large capacitor and leave it running, it can deliver a lethal shock.

--- End quote ---

Exactly.

The other poster mentioned a "50-100 thousand volt Van-De-Graaf generator which has no ability to supply the 'current'". That's not how it works - as you say, if you present an impedance the voltage has to collapse. That being said, the dome holds a charge and will discharge a given amount of energy if touched without previously being discharged. In this case, the peak current can be many amperes.
TheBay:
When I was an electronics engineer for LG one of workers that was stationed on the line reject repair bin had extraordinary stats for repairs or diagnosis and we couldn't figure out how.

He was asked to go to Korea to train some staff there. On the first night there he was invited out with the staff that he was training and somehow manged to get them that drunk they were seriously ill and off work for 2-3 days with hangovers/alcohol poisoning.

When that settled down he started training the staff. And promptly got reprimanded.
It turns out he thought using a multimeter took too long to fault find, his method was pulling the PCB out of the CRT Monitor/TV and touching B+,G1, G2 and other voltages while it was powered up! That did not go down well at all in Korea or back in the UK.

In the same factory a CRT monitor went down the production line and one of the line workers noticed the "Red cable" wasn't connected to the CRT, so they grabbed the EHT lead and tried to clip it in to the tube, while leaning over the production line. The shortest path to earth was through his genital area. He seriously felt that but was okay after a visit to the hospital.

My late father was an industrial engineer, fabricator and welder.
He always maintained the worst electric shocks he had by far ( Even getting shocked working with single 240V and 3 Phase) was from Arc welders, especially if he was sweaty or in a pool of water.
Siwastaja:
If it's "current that kills", then you may want to try to explain yourself how RCDs are able to save lives. Note, they can't limit current, it is what it is; they only limit the time.

No need to reply to me; I'm not interested in social games. I prefer intellectual honesty so work it out in your own head. It's not all that complex if you choose to ignore rules developed 100 years ago for explaining things to laymen using bad analogies. Instead, work with the basic units available to us scientists and engineers. Voltage, current, resistance, impedance, power, time, energy... For example, a high-impedance high-voltage supply forms a classic voltage divider with the body impedance, and the lower the body impedance, the lower the voltage over body. Think about all of this instead of playing social games.
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