4 ms·

The U.S. does use 220-240v for some applications and every house is wired for it--at least to the panel. Large appliances, car chargers, and other high current

The U.S. does use 220-240v for some applications and every house is wired for it--at least to the panel. Large appliances, car chargers, and other high current devices are almost always 220-240v in the home. But 240v between your hand and ground is twice as likely to stop your heart.

sidewndr46 1y ago
No, not all homes are wired to that voltage. Some have 120 only. Some are 208. Some are 480 if they need lots of power
- Kirby64 1y ago
  > No, not all homes are wired to that voltage. Some have 120 only. Some are 208. Some are 480 if they need lots of power There are exceedingly few homes, especially single-family homes, in the US that do not have split-phase 240V power. 208V (2 legs of 3-phase) power is almost always relegated to condos or apartments and never single-family homes. Even in that case, many 240V appliances function just fine on 208V albeit at a lower maximum power. Even fewer still, to the level that you don't have a 'home' at that point but, but a small commercial building, have 480V power. Only commercial buildings have 480V, and they basically always will have conversions to usable residential power for using... normal stuff.
  - justinclift 1y ago
    > Only commercial buildings have 480V ... People do get it hooked up in garages and similar to run industrial/hobby equipment. ie lathes and stuff along those lines
    - Kirby64 1y ago
      Right, so if you’re getting 480V hooked up you have a small commercial building at that point. And you probably still have 240V feed for the rest of the house. Also, these days you have many more options than just getting 480V. Running a VFD off 240V to generate 3-phase is much more affordable generally for a used lathe or something. Even getting 480V connected to a house is sometimes impossible, or at very least so expensive it makes no sense.
      - justinclift 1y ago
        > so if you’re getting 480V hooked up you have a small commercial building at that point. Doubt it. Pretty sure that'd require a zoning change, but who knows... ;)
schlauerfox 1y ago
anything over a certain voltage can be lethal. I can't find evidence it's linear like you're saying? I'll take it as a joke.
- hulitu 1y ago
  > anything over a certain voltage can be lethal. current
- jschveibinz 1y ago
  No, not really a joke. Humans have a characteristic impedance and Ohm's Law is in fact linear. So higher voltage, higher current, and higher likelihood that the current finds a path through the heart.
HarHarVeryFunny 1y ago
240V will give you a jolt, but it's really not that bad, at least if it's quick. I grew up in the UK and got my fair share of 240V shocks as a kid - from bare feet touching bare wires/connectors under the table, to me lighting up a small dolls house light bulb by poking stripped pieces of wire into a wall socket, while holding the other end with bare fingers onto the light bulb! I'm not dead yet! You can even get a 480V shock if you short yourself across two wall sockets wired to alternate phases (+240V, -240V).
- tangent-man 1y ago
  'it's really not that bad, ' 'I'm not dead yet!' That's not how Science / Engineering works. Just because you (one person) have survived various misadventures with 240v (so far) doesn't mean its safe by any means. The point is 240v at Household amps / current CAN kill you. It just hasn't YET
  - eqvinox 1y ago
    > The point is 240v at Household amps / current CAN kill you. Deaths from electrocution are low in the US at 110V, but not massively higher at 230V; some 230V countries are lower in fact: https://www.researchgate.net/figure/Age-adjusted-mortality-rates-from-electrical-injuries-per-1-million-population-European_fig1_221916189 https://www.researchgate.net/figure/Age-adjusted-mortality-r... (Says at bottom 0.63 for US) Apparently eastern European electrons are more deadly though ;D (... It's really all about safety culture.) Also, that male/female split in the linked graph... wow.
    - HarHarVeryFunny 1y ago
      > Also, that male/female split in the linked graph... wow. That is pretty funny ... It's a wonder that men haven't gone extinct yet.
      - eqvinox 1y ago
        At first I thought it'd be male children, but I don't think that's it - male electricians and other workers is more likely. Also, I don't have a reference, but it's stuck in my head that deaths from electrocution frequently involve falling off a ladder (or other "secondary" causes), rather than dying from cardiac arrest or other direct injury.
eqvinox 1y ago
If you compare "to the home panel", that's 380~400V in most "230V" countries. Three phase of course.
FireBeyond 1y ago
> But 240v between your hand and ground is twice as likely to stop your heart. No. It's the amperage that kills. Yes, in reality, 240V circuits are likely to have higher-amperage devices attached. One milliamp at 240V will not kill you. That's why our defibrillators (I am/was a critical care paramedic) have a set voltage, and if we need to deliver a bigger shock, we turn up the joules for delivery.
- deleted 1y ago
  [deleted]
- addaon 1y ago
  > It's the amperage that kills. Yes, in reality, 240V circuits are likely to have higher-amperage devices attached. One milliamp at 240V will not kill you. If a circuit is formed from a 240 V source, through you, to a low-impedance ground, and to the extent that you can be modeled as a resistive load (quite well), the amperage flowing through you (until the breaker opens, if it does) will be twice the current that would flow through you from a 120 V source in the same situation. Current kills, and 240 V sources provide 2x the current into a load as a 120 V source, if you're the load.

sidewndr46 1y ago

No, not all homes are wired to that voltage. Some have 120 only. Some are 208. Some are 480 if they need lots of power

Kirby64 1y ago
> No, not all homes are wired to that voltage. Some have 120 only. Some are 208. Some are 480 if they need lots of power There are exceedingly few homes, especially single-family homes, in the US that do not have split-phase 240V power. 208V (2 legs of 3-phase) power is almost always relegated to condos or apartments and never single-family homes. Even in that case, many 240V appliances function just fine on 208V albeit at a lower maximum power. Even fewer still, to the level that you don't have a 'home' at that point but, but a small commercial building, have 480V power. Only commercial buildings have 480V, and they basically always will have conversions to usable residential power for using... normal stuff.
- justinclift 1y ago
  > Only commercial buildings have 480V ... People do get it hooked up in garages and similar to run industrial/hobby equipment. ie lathes and stuff along those lines
  - Kirby64 1y ago
    Right, so if you’re getting 480V hooked up you have a small commercial building at that point. And you probably still have 240V feed for the rest of the house. Also, these days you have many more options than just getting 480V. Running a VFD off 240V to generate 3-phase is much more affordable generally for a used lathe or something. Even getting 480V connected to a house is sometimes impossible, or at very least so expensive it makes no sense.
    - justinclift 1y ago
      > so if you’re getting 480V hooked up you have a small commercial building at that point. Doubt it. Pretty sure that'd require a zoning change, but who knows... ;)

schlauerfox 1y ago

anything over a certain voltage can be lethal. I can't find evidence it's linear like you're saying? I'll take it as a joke.

hulitu 1y ago
> anything over a certain voltage can be lethal. current
jschveibinz 1y ago
No, not really a joke. Humans have a characteristic impedance and Ohm's Law is in fact linear. So higher voltage, higher current, and higher likelihood that the current finds a path through the heart.

HarHarVeryFunny 1y ago

240V will give you a jolt, but it's really not that bad, at least if it's quick. I grew up in the UK and got my fair share of 240V shocks as a kid - from bare feet touching bare wires/connectors under the table, to me lighting up a small dolls house light bulb by poking stripped pieces of wire into a wall socket, while holding the other end with bare fingers onto the light bulb! I'm not dead yet! You can even get a 480V shock if you short yourself across two wall sockets wired to alternate phases (+240V, -240V).

tangent-man 1y ago
'it's really not that bad, ' 'I'm not dead yet!' That's not how Science / Engineering works. Just because you (one person) have survived various misadventures with 240v (so far) doesn't mean its safe by any means. The point is 240v at Household amps / current CAN kill you. It just hasn't YET
- eqvinox 1y ago
  > The point is 240v at Household amps / current CAN kill you. Deaths from electrocution are low in the US at 110V, but not massively higher at 230V; some 230V countries are lower in fact: https://www.researchgate.net/figure/Age-adjusted-mortality-rates-from-electrical-injuries-per-1-million-population-European_fig1_221916189 https://www.researchgate.net/figure/Age-adjusted-mortality-r... (Says at bottom 0.63 for US) Apparently eastern European electrons are more deadly though ;D (... It's really all about safety culture.) Also, that male/female split in the linked graph... wow.
  - HarHarVeryFunny 1y ago
    > Also, that male/female split in the linked graph... wow. That is pretty funny ... It's a wonder that men haven't gone extinct yet.
    - eqvinox 1y ago
      At first I thought it'd be male children, but I don't think that's it - male electricians and other workers is more likely. Also, I don't have a reference, but it's stuck in my head that deaths from electrocution frequently involve falling off a ladder (or other "secondary" causes), rather than dying from cardiac arrest or other direct injury.

eqvinox 1y ago

If you compare "to the home panel", that's 380~400V in most "230V" countries. Three phase of course.

FireBeyond 1y ago

> But 240v between your hand and ground is twice as likely to stop your heart. No. It's the amperage that kills. Yes, in reality, 240V circuits are likely to have higher-amperage devices attached. One milliamp at 240V will not kill you. That's why our defibrillators (I am/was a critical care paramedic) have a set voltage, and if we need to deliver a bigger shock, we turn up the joules for delivery.

deleted 1y ago
[deleted]
addaon 1y ago
> It's the amperage that kills. Yes, in reality, 240V circuits are likely to have higher-amperage devices attached. One milliamp at 240V will not kill you. If a circuit is formed from a 240 V source, through you, to a low-impedance ground, and to the extent that you can be modeled as a resistive load (quite well), the amperage flowing through you (until the breaker opens, if it does) will be twice the current that would flow through you from a 120 V source in the same situation. Current kills, and 240 V sources provide 2x the current into a load as a 120 V source, if you're the load.