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back in tradeschool for becoming a heavy duty mechanic I'll never forget what the teacher told us about electric shock.
It's not the 100000volts that kills the mechanic checking the ignition coil.
It's the secondary hood latch he impaled himself with when he jumped.....

This is incorrect - Europe has a 230V hot and a neutral. Source: I lived in Germany for 6 months setting up a manufacturing facility and I have been designing industrial control panels for sale in Europe for almost a decade. All circuits also have to be protected by an RCD in homes and offices and they are 230V nominal to ground (anywhere from 220-240V depending on location). There is no high and low voltage in homes - everything is 230V 50Hz single phase with a hot and a neutral.

In the industrial buildings, the 230V is actually derived from the 3-phase 400V incoming along with a neutral - same thing for apartment buildings. They also do this in North America with 208V 3-phase for some apartment buildings to save on wiring (you lose a bit of output on your 240V resistive heaters like your oven).

Japan is a weird one (we also have an office there) - the household voltages are 100 and 200V, kind of like we do it (hot and neutral for low voltage and 2 hots for high), but there is no ground at the plug. They use a completely different grounding system that I don't fully understand - they only ground at each end of the distribution and there is no ground connection back to the source. It is called a "TT" or Terre Terre system. All outlets are protected by an RCD there also. They are also split between 50Hz and 60Hz and have to have a massive frequency link in the middle of the country to deal with it.

I have been "zapped" a few times here in the states. At home due to previous homeowner thinking it would be a good idea to switch the neural wire in all of the lights... I turned it off and didn't check with a meter since the light went off - I assumed it was off. Nailed me pretty good. The worst was here at work when I was younger and very hung over. I was testing systems and got into a rhythm connecting, testing, disconnecting, etc. Forgot to turn off the juice on one of the steps and grabbed my screwdriver shaft while it was in the distribution block. It was 480V 3p, so 277V to ground - and it hurt like hell for about a week.

Edit - I am new here and thought I was responding to a specific post that claimed 230V in Europe was 2 hots like we are here in the US. Sorry for the confusion. I will get better. I also now see several others already corrected it...

Originally Posted by pecmsg

I’ll respectfully disagree
Accidents Shouldn’t happen and every step needs to be takin to prevent them. There is an extremely fine line between accidents and D E A T H! This is a line WE do not want to cross!

And this right here is why we need education.

Originally Posted by szw21

Not sure where you got this information. Do you have link(s)? FWIW I used to live in the UK - in fact still have property there - and I've done my fair share of house wiring projects - outlets, light fixtures etc. I never heard to 2 hot legs - the wiring was live and neutral. Home there are served by 3 phase circuits with each home on a different phase and marked by a color in the breaker panel to indicate the phase the home is on.

I was chatting to a friend over there today who's an EE - he's never heard of 2 hot legs either.

Here is a link from the BBC about the domestic supply there - see page 2. https://www.bbc.co.uk/bitesize/guide...2nb/revision/2

I cannot speak for other parts if Europe but I always though the 2 hot leg setup was a US thing.

News to me, sorry if I was wrong. That certainly would make no sense.

As a 13 years old I was trouble shooting a 220v light bulb socket. The bulb socket was the kind that had 2 spring loaded contacts for bayonet bulb base. After 5 minutes checking the voltage on the 2 wires with a meter, I started thinking the spring loaded contacts were not extended far enough for making contact to the bulb, and my mind drifted to mechanical mode instead of electrical. I was standing on wooden floor and pushing on one contact by one finger to feel the spring tension, then I pushed both contacts with 2 fingers of same hand. The current ran through the 2 fingers and it hurt so bad the pliers flew off from the other hand across the floor.

Originally Posted by Red Man

I’ve been shocked by 24 volts. It’s not a bad shock but is surprising because it’s so unexpected. I figure wet hands and a short path to ground causes it.

You enjoyed too much beef; high in iron. I wouldn't feel a thing on 24v unless using tongue.

Hot and sweaty is perfect for conducting electricity including 24 Volts!

I’ve been shocked by 24 volts. It’s not a bad shock but is surprising because it’s so unexpected. I figure wet hands and a short path to ground causes it.

Originally Posted by stumpdigger

Europe does NOT have a nominal 230 vac hot leg and a neutral Toi'di, they use two hot legs just like here in the U.S. for 230 VAC

Not sure where you got this information. Do you have link(s)? FWIW I used to live in the UK - in fact still have property there - and I've done my fair share of house wiring projects - outlets, light fixtures etc. I never heard to 2 hot legs - the wiring was live and neutral. Home there are served by 3 phase circuits with each home on a different phase and marked by a color in the breaker panel to indicate the phase the home is on.

I was chatting to a friend over there today who's an EE - he's never heard of 2 hot legs either.

Here is a link from the BBC about the domestic supply there - see page 2. https://www.bbc.co.uk/bitesize/guide...2nb/revision/2

I cannot speak for other parts if Europe but I always though the 2 hot leg setup was a US thing.

I had 30 days leave in 1970 before going overseas. I decided to add some wiring in my mother's basement.
I borrowed a 1/2" Sioux drill, AKA known as arm busters with double side handles, all steel construction, and in this case the 3rd prong cut off of the cord end. (The old guy who loaned it didn't need such nonsense.....and grounded outlets were sometime rare.)

I am drilling thru bsmt floor joists. I always check the opposite side for pipes and wires.
There is a 24" extension on the high speed 3/4" bit.
I drill thru and get zapped......I had checked the wrong joist.

I was wearing a metal band wrist watch.
It was in solid contact with a well grounded cold water pipe.
Hands closed around both handles.
I knew I had to let go, but the lock button on the trigger switch had gotten engaged.
I am thinking if I let go the drill will fall out on top of me on the floor.
I pick my feet up doing a chin up on the drill, thinking my grip would give up.

The black curtain was descending/coming down over my eyes.
(If you have never had that happen, that is literally what it seems like.....you are losing conscience about to pass out)

Back to where I was worried about the drill falling on me, as I picked up the feet I tried to get a little jump to get clear.

Just then the drill bit which had hit the black wire in the romex finally found the white also.
That blew the fuse shutting down the outlet I was plugged in.

Hand grip was broken and I did get a little jump hitting the floor firmly on my chest.
I believe that was the "cardiac thump" that started my engine again.

All of this took less than 2 seconds to occur. All the thoughts about the drill locked on, falling out, do a pull up on the handles and jump away when possible occurred in that time.
I was unconscious as the hands released and the short trip thru the air.
The face down on the concrete with a sore chest was the next thing I remember.

So lessons learned:
No jewelry worn while working, not even wedding ring.
Use hand to feel opposite side of wood before drilling.
Keep 3rd prong on cord end or have double insulated tool.

50 years later I distinctly remember that incident where my angels were present.

Methinks you got zapped by residual charge on the capacitor via the contactor connection, not by 24 Vac.

Which brings up another aspect - when running the connection point between a motor and run capacitor can be more than TWICE the operating voltage due to resonance. There are a number of documented fatalities of even HOs from an ungrounded window shaker case have come into contact witht he point via frayed wire.

Originally Posted by stumpdigger

In the first place the most probable way to loose one leg on a 220 system is for something to go to ground thus tripping a double pole breaker.
Touching one side of a 240 system IS a 120 vac and you are likely grounded.
Europe does NOT have a nominal 230 vac hot leg and a neutral Toi'di, they use two hot legs just like here in the U.S. for 230 VAC

No. Its one hot leg, a neutral, and a safety ground.

Not two hot legs like here.

Originally Posted by junkhound

24V?
Am assuming 24 Vac, 60 Hz, 32 V peak.

Please describe the setup, were you working with wet hands standing on concrete floor in bare feet or wet leather shoes? Or did you have a cut on your hand or a splinter?

Have never even been able to even feel 24 Vac 60 Hz unless skin is broken or beading perspiration.

Which is another safety aspect - anything wet extra caution.

The power was off on the outdoor unit, I was doing a routine tuneup. The thermostat had the contactor pulled in though, and when fumbling around with the capacitor trying to get a wire off my hand slipped and the backside of my hand touched the one side of the contactor where the thermostat wires go. BZZZZT! and I yanked my hand away. Wearing my usual army work boots. I don't remember how I was positioned but It's probable my other hand was on the condensing unit bracing my body weight?

Originally Posted by Sapote

The statistic because people exposed to 120v more than 240v or higher. It's not because 120 is more dangerous than 240.
Same body part under 240v gets more current flow than when under 120v. Then why people say 120v is more dangerous than 240v?



Most people didn't get shock from 240v because they only touched 120v surface and reference other body part to ground. It's a low probability to have the body touched on both hot legs to have 240v across.

In other part of the world, you have 240v on one hot leg and the other is ground or neutral. Deadly.

In the first place the most probable way to loose one leg on a 220 system is for something to go to ground thus tripping a double pole breaker.
Touching one side of a 240 system IS a 120 vac and you are likely grounded.
Europe does NOT have a nominal 230 vac hot leg and a neutral Toi'di, they use two hot legs just like here in the U.S. for 230 VAC

Originally Posted by szw21

It would be interesting to know why the US has this system. Other than the US, Canada and possibly a couple of other countries, the rest of the world has 240V AC single phase for residential - there is no 120V option.

To the best of my knowledge the 120vac was adopted from the very beginning of deciding on and building a distribution system. Thomas Edison wanted to run DC and thankfully we had Tesla who knew DC was not viable. Edison used to electrocute animals in public in a desperate attempt to sway the government et al to adopt DC. Tesla won out of coarse otherwise we would be in the dark ages.
Europe soon realized that their electrical infrastructure was too weak and switched to "230 VAC" by loosing the neutral and using two hot legs so that amperage could be cut by half at least.

Been shocked enough times to know I can be an idiot at times.

Crashed a motorcycle enough times to know I can be an idiot at times.

Burned my arms while welding enough times to know I can be an idiot at times.

Cut myself enough times to know I can be an idiot at times.

It doesen't "Just Happen"

You did something that made it happen, that's how I see it.

Originally Posted by Sapote

I think 120v was used in US because it is safer than 240v. One would die by the high voltage before the fingers were vaporized.

I once almost lost my index finger trying to jump start a dual V8 engine on a boat. It had 24v high capacity marine battery. The old oxidized ignition was unreliable and I used a short piece of 18 gauge wire to jump the starter solenoid relay, and this became just an auto pilot act. Then one day I mistakenly jumped directly to the starter big nut and it was like a camera flashlight, the 18 gauge wire vaporized instantly; nothing, not even the insulator remained. I smelled burned meat and my finger had a 5mm deep burn. I could have lost the finger if the wire was wrapped around it.

Originally Posted by Sapote

The statistic because people exposed to 120v more than 240v or higher. It's not because 120 is more dangerous than 240.
Same body part under 240v gets more current flow than when under 120v. Then why people say 120v is more dangerous than 240v?



Most people didn't get shock from 240v because they only touched 120v surface and reference other body part to ground. It's a low probability to have the body touched on both hot legs to have 240v across.

In other part of the world, you have 240v on one hot leg and the other is ground or neutral. Deadly.

Originally Posted by Sapote

240v single phase is more efficient but also more dangerous.

God help me!

Originally Posted by szw21

It would be interesting to know why the US has this system. Other than the US, Canada and possibly a couple of other countries, the rest of the world has 240V AC single phase for residential - there is no 120V option.

240v single phase is more efficient but also more dangerous.

Originally Posted by stumpdigger

99.9% of homes are fed with 240 Vac, it's just a question of how many hot legs you are using. 120 Vac kills more people in this country than all of the other voltages combined.

The statistic because people exposed to 120v more than 240v or higher. It's not because 120 is more dangerous than 240.
Same body part under 240v gets more current flow than when under 120v. Then why people say 120v is more dangerous than 240v?

Originally Posted by stumpdigger

the worst case is that you lose the nuetral which does not break a circuit and the hot leg is looking for a path to ground.

Most people didn't get shock from 240v because they only touched 120v surface and reference other body part to ground. It's a low probability to have the body touched on both hot legs to have 240v across.

In other part of the world, you have 240v on one hot leg and the other is ground or neutral. Deadly.

Originally Posted by stumpdigger

99.9% of homes are fed with 240 Vac, it's just a question of how many hot legs you are using. 120 Vac kills more people in this country than all of the other voltages combined. Yes you will get stuck on a hot surface (as on an old non double insulated metal body drill) , the worst case is that you lose the nuetral which does not break a circuit and the hot leg is looking for a path to ground.

It would be interesting to know why the US has this system. Other than the US, Canada and possibly a couple of other countries, the rest of the world has 240V AC single phase for residential - there is no 120V option.