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| The real reason why North America uses 120v instead of 240v. |
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| themadhippy:
--- Quote ---Why not have 120V be 2x 60V to ground? Wouldn't that be the safest way to have 120V? --- End quote --- We do in the uk.ok its 55-0-55v ,it mainly used on construction sites. |
| Monkeh:
--- Quote from: snarkysparky on November 25, 2022, 11:18:22 am ---My guess is that the vast majority of electrical shock fatalities are in industrial settings. 480 VAC and much higher. So unless there is data that breaks our household electrical shock fatalities the data is meaningless to the discussion. --- End quote --- Of the 13 I mentioned in England, 7 were in homes - no 480VAC in homes. Actually, no 480VAC at all, not that shocks between phases are common.. In 2020, there were 14 - 4 of them in homes. Of the 126 workplace fatalities in the US, 13 examples were given. Three were almost certainly only 120VAC, a fourth highly unlikely to be greater than that. The others vary, several are likely to have been 120VAC and a few more, 277VAC (one phase of 480VAC, because again, contact between phases is unlikely). Contact with overhead lines is remarked to be the most common cause, however, but the voltage of those is unspecified. 120VAC lines are much lower down than higher voltage supplies, of course.. As a curious aside which I'm tempted to contact the ONS about, in 2018 a 7 year old boy was electrocuted at a pub in Essex by faulty outdoor lighting. This age group does not appear in the released data.. |
| AVGresponding:
--- Quote from: Monkeh on November 25, 2022, 02:55:47 pm --- --- Quote from: snarkysparky on November 25, 2022, 11:18:22 am ---My guess is that the vast majority of electrical shock fatalities are in industrial settings. 480 VAC and much higher. So unless there is data that breaks our household electrical shock fatalities the data is meaningless to the discussion. --- End quote --- Of the 13 I mentioned in England, 7 were in homes - no 480VAC in homes. Actually, no 480VAC at all, not that shocks between phases are common.. In 2020, there were 14 - 4 of them in homes. Of the 126 workplace fatalities in the US, 13 examples were given. Three were almost certainly only 120VAC, a fourth highly unlikely to be greater than that. The others vary, several are likely to have been 120VAC and a few more, 277VAC (one phase of 480VAC, because again, contact between phases is unlikely). Contact with overhead lines is remarked to be the most common cause, however, but the voltage of those is unspecified. 120VAC lines are much lower down than higher voltage supplies, of course.. As a curious aside which I'm tempted to contact the ONS about, in 2018 a 7 year old boy was electrocuted at a pub in Essex by faulty outdoor lighting. This age group does not appear in the released data.. --- End quote --- Larger homes often have 3-ph supplies in the UK. |
| Monkeh:
--- Quote from: AVGresponding on November 25, 2022, 03:38:23 pm ---Larger homes often have 3-ph supplies in the UK. --- End quote --- I wouldn't say often, and many DNOs actively refuse to supply such. And still not 480VAC. Mind you, there's the far rarer option of a split-phase supply.. never say never, I guess. |
| mcovington:
--- Quote from: Tangent_Tracker on November 25, 2022, 11:55:28 am --- --- Quote from: IanB on November 24, 2022, 07:57:18 pm --- --- Quote from: MikeK on November 24, 2022, 06:55:04 pm ---Do countries that use 240V have two out-of-phase 120V lines (like the US actually has), or do they just have a single 240V line? --- End quote --- It is single phase 240 V, but wiring and appliances are supposed to assume that both line and neutral conductors are live, and each has to be equally insulated from any exposed parts that could be touched. --- End quote --- We certainly have the safest plug and socket system in the world I think. That is our saving grace. --- End quote --- Are you referring to the UK, Australia, or somewhere else? The tiny plugs in the US certainly don't give me a lot of confidence. |
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