Electrical Safety

60Hz disrupts the heart and 50Hz doesn’t? I have a hard time believing that slightly lower frequency makes such a large difference.

I have heard that AC, 50 or 60Hz, is more likely to cause fibrillation and therefore death than DC, because DC is more likely to just cause the heart to lock up until after the shock ends. Subject to damage from heat, of course.

Also, my mantra has been Volts Hurts, Amps Kill. Voltage alone can still kill you, but it requires being at extremely high voltages (At least 20kV, though this is a guess, I know that I’ve watched a coworker get shocked by about 15kV without lasting harm, though it hurt) and usually results in a major explosion where the concussion kills you. However, that is assuming no current.

This is a dangerous thing to say on any forum with newbies. As has been pointed out, 12V can shock you. If you were to pierce the skin in two places, say both hands or a hand and opposite foot, 12V could electrocute you (electrocute = kill, shock is if you survive).

Drop a wrench across the 240Vac line coming into your house, you’ll see an arc flash with a concussion that can kill you and set nearby flammables ablaze. No way, shape, or form does it require “at least 20kV”.

Your coworker was hit with, let me guess, a neon sign transformer? Those are current limited. As low as 10mA. FYI, there is no such thing as voltage with no current.

Look up arc flash on Youtube. In one case, there is a story of a worker who thought he was measuring 440Vac and put the wrong meter across a 2kV line. The resulting arc flash jumped from the meter to him and then across the lines, set his clothes on fire heat to toe, blew him back into the wall, and eventually killed him a day or two later.

Once an arc forms, the resistance is relatively low. Your flesh, once you get beyond the skin, has only a hundred ohms or so of resistance, even from one arm to another. I did some testing with a current limited high voltage power supply that I designed and built. And that is at very low currents. At higher currents, as someone pointed out, cell walls rupture and the resistance goes down.

And even with relatively casual contact, 60V can do you in. Get a hand locked in place by the current, and you get to hang on the wire and slowly cook to death. Or muscular reaction throws you into something, causing secondary injuries that may be fatal.

Voltage without current, otherwise known as static electricity....

GoForSmoke:
Rainwater will have a little dust in it, it’s not pure.

Correct but parts per million makes the dust speck in each drop of rain non applicable.
I actually tested this as a kid in grade 5/6.
perhaps with all the chemtrails these days it might produce a different effect. Maybe I will try it again, if it would rain and not snow for a day or two.

Melt the snow, but sweep the top layer off first before you collect any. I am sure that once power is applied that the small impurities will find an electrode quickly enough, maybe stick? Pure water has a dielectric constant of 81 where air = 1.

Chemtrails? That's what clueless people who see contrails call them. I've seen one video where a California woman is showing the rainbow here lawn sprayer in making on a bright, sunny day. But to her it's not a rainbow, it's chemicals in the water supply just like the chemtrails chemicals! It's a huge plot to kill us all, not natural in the slightest! What a dizzy bitz!

About 30 years ago if not longer there was enough acid in acid rain to slowly kill trees. Today the rate of burning is higher, because when you're running out of something the thing to do is use it up faster and faster.

Voltage without current, otherwise known as static electricity....

Voltage requires charge displacement.

Why do you think you go "ouch!"

So-called "Static" electricity is just a build-up of voltage through charge separation. Lightning is "static" electricity. Within the realm of everyday life, I had a car that would just about knock me on my behind on dry days as I was getting out.

polymorph: Within the realm of everyday life, I had a car that would just about knock me on my behind on dry days as I was getting out.

I learned to keep my hand on some part of the metal as I slide out. This allows a small current to flow over the time it takes to get out of the car instead of one enormous current when you shut the door. Insulation-blowing machines can also create giant 6" sparks from their hoses on dry days. It is quite surprising when you walk too close to one to say the least.

I got into static back in school over 40 years ago though I never built a generator. Voltage is electrical potential.

If you work in a place with compressed air to run machines with, it's got a little oil in it, then take a plastic bowl and give it a good spraying. Then find a victim, smile, point into the bowl and say "juice" but don't say touch or not, let them stick a finger in to show you there's no juice in that bowl. ]:D

InPhase277: I learned to keep my hand on some part of the metal as I slide out. This allows a small current to flow over the time it takes to get out of the car instead of one enormous current when you shut the door. Insulation-blowing machines can also create giant 6" sparks from their hoses on dry days. It is quite surprising when you walk too close to one to say the least.

I do exactly the same when the weather is dry, otherwise I can draw a spark that makes my arm buzz to the elbow! :astonished:

I actually think, that I and the car work as an electrophorus, unless the electrons are allowed to flow back slowly.

And in dry weather, I touch the door handles at work with my keys or a penknife before opening the doors at work. I can draw a couple of cm long sparks on a "good" day.

how about attaching a small neon bulb to the car, to absorb any static build up?

How would you attach the bulb?

cjdelphi: how about attaching a small neon bulb to the car, to absorb any static build up?

I think the problem is, that the charge build up is between the driver and the seat.

My hineys are busy rubbing electrons off the seat while driving, and when I get out, the charges are separated. That also explains, why the effect of the "lightning rod" some people attach to their cars, is quite limited.

Wearing plastic fiber clothes don't help. I spent time at the local VA where the carpets were like some kind of Van Der Graff belt. Get up to a door and the habit is to grab the handle and get zapped. I took to touching the painted part of the metal door and while no zap, I could feel the effect of the charge bleed (human, I feel it after it's happened as if it still is). Some time in the past the DoD bought a bazillion gallons of oil based paint and it makes a good resistor.

I have a scare when there's casual static because I am a computer user.

https://www.youtube.com/watch?v=rMIdOThUYfo

But there is some fun to it! Sneak up to a friend, and touch a finger to his ear. ]:D

When my kids were small, they had a plastic chute for playing. Sometimes they played "Pikachu", meaning that one of them would slide halfway down and stop, then touch a finger to the nose of the other, standing next to the slide, and draw an audible spark. They considered it great fun.

fungus: https://www.youtube.com/watch?v=rMIdOThUYfo

My goodness! :astonished:

what was that? Had he thrown some kind of conductive string over the wires?

fungus: https://www.youtube.com/watch?v=rMIdOThUYfo

Then later to complain about poor electrical service. It is way.

After thinking about it, the neon bulbs would have to be connected inside door frames so it sits between you and the car ... not as straightforward as I thought at 3am

Actually, while you are in the car, you have no charge (assuming you are touching the key in the ignition or some other metal part.

The car picks up charge as it moves through the air, and probably some interaction with the tires.

When you step out, you discharge the car. It isn't actually you that has the charge built-up. So what you need to help keep the car discharged is a light wire or chain hanging down.

They used to be called ground straps.

polymorph: Actually, while you are in the car, you have no charge (assuming you are touching the key in the ignition or some other metal part.

The car picks up charge as it moves through the air, and probably some interaction with the tires.

When you step out, you discharge the car. It isn't actually you that has the charge built-up. So what you need to help keep the car discharged is a light wire or chain hanging down.

There are two theories, and you represent one of them here: "The charge buildup is between the car, and the rest of the world. You get zapped, because you form the path to discharge the car"

The other one is:"The charge build up is between you and the car. When you get out, you separate the charges, increasing the voltage. The discharge is between you and the car"

I believe in the second explanation. (And I have had ground straps on cars. In my case, they didn't work at all)