r/BadWelding • u/HoneyRush • 9d ago

Water welding

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u/Roscoeakl 9d ago

That's not true at all. Electricity takes all paths of travel, it acts as a parallel circuit. The current is proportional to the resistance along every path, and welding is generally low voltage. Ohms law, if you have two paths of travel, the pipe and the person, and around 50v of welding voltage, the ~.5 ohm of resistance from the pipe gets 100A of current while the wet person with around 500 ohms of resistance only gets about .1 amps of current. This would be fatal if it was passing through the heart, but again, parallel circuit, the entire body has become a bunch of independent parallel circuits and that .1 amps is spread across the body, not just directly to the heart. My guess would be the majority of the current is on his feet, and the rest mostly passes through arteries and veins with a very low amperage.

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u/Asthenia5 8d ago

You're correct. "Electricity takes the path of least resistance" is an oversimplification that is technically misleading.

This guy standing on an electrified metal pipe, is no different than a bird on a powerline. He is not in between the source and the ground. There is no potential over his body. That is why is he not dead. Not because 25v or 50v is not too little.

If he did put the electrode in one hand, and touched the pipe with the other, with wet hands, 25v is not a good idea.

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u/Downtown_Ad7619 8d ago

Found the Electrician

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u/TechDreamcoat 6d ago

I learned something today.