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Old 02-25-2019, 01:55 PM   #11
gunrunnerjohn
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Good Grief! I would think a 2F cap at 600V would melt the battery cable, that's 360,000 Joules!!! When I was a young lad I had an array of one hundred 200uf 1,000V capacitors that I charged up to around 800 volts, that's only 6,400 Joules. I had a very large knife switch to dump the charge into a custom cone with a fine lead wire to start the arc, it would break coke bottles eight to ten feet! The loud crack of the arc was probably why I have poor hearing to this day, it put any gun I've ever fired to shame! Your rig would kill a herd of elephants, and I think audible crack would be a massive understatement of the sound! The shock wave coming from that would have to be been immense, hard to believe that there wasn't damage around the lab from that little experiment.

I won't even get into the wisdom of actually doing what you describe. I was a stupid high school student with no supervision when I was doing my little rig, how a college lab allowed you to do that defies any logic.
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Old 02-25-2019, 01:59 PM   #12
Shdwdrgn
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Quote:
Originally Posted by gunrunnerjohn View Post
Lightning!
No no, that's not 500 volts. Lightning gives you 1.21 gigawatts!


Quote:
Originally Posted by gregc View Post
...it can only charge to the voltages in the system...
Voltage doesn't kill you, amps kill you. Tesla coils can pump millions of volts through your body without harm, but you can stop a heart with 1/10th of an amp. If you had to use battery cables to discharge those caps, there's no way I'd risk letting that charge go through my body.
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Old 02-25-2019, 03:27 PM   #13
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Voltage doesn't kill you, amps kill you. Tesla coils can pump millions of volts through your body without harm, but you can stop a heart with 1/10th of an amp.
if skin resistance is 2k Ohms, what voltage is required to drive 1/10 A through your body?
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Old 02-25-2019, 04:41 PM   #14
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if skin resistance is 2k Ohms, what voltage is required to drive 1/10 A through your body?
According to ohms law, that would be 200 volts. However, if your skin is slightly damp, you'll have a skin resistance less than 2K!

You may be asking how I know that. That's simple, tons of people have been killed by 110VAC, so they obviously had considerably less skin resistance, or it took less current to kill them. Either way, they're dead!
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Old 02-25-2019, 04:44 PM   #15
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so are DCC voltages likely to give you a jolt even if the equipment is capable of delivering more than 1/10 A? (rhetorical)
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Old 02-25-2019, 04:53 PM   #16
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You can get shocked from 12VDC in your car. If you manage to get it in open wounds, it can actually give you a decent jolt.
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Old 02-25-2019, 04:56 PM   #17
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so if its an open wound, it's not going thru the skin. I don't know what the resistance is of living tissue.

or do you mean the coil, 14 kV? someone told me they got knocked across the room getting shocked by the coil.
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Old 02-25-2019, 07:14 PM   #18
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So what im gathering is that there really isn't a way to make a current keeper from scratch. ie schematic, video, forum. I don't know electronics to well so I was looking for a detailed description on how to build one.
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Old 02-25-2019, 07:15 PM   #19
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Stick your tongue on a 9 volt battery, you'll git a little nip! I recall determining if 1.5v batteries were good by licking a finger and sticking it on one end and then touching my tongue to the other end, good if tasted a little sour. Unlike you two, I didn't mess with high voltage! Maybe because I spent my summers working as an electrician.
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Old 02-25-2019, 07:17 PM   #20
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So what im gathering is that there really isn't a way to make a current keeper from scratch!
you certainly can build your own.
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