Comments by "seneca983" (@seneca983) on "Perhaps the weakest link in the US electrical system" video.

@John Jenkins "Electrician here, good theory on why wires are uncoiled before use but not the actual reason. If youve ever seen the windings inside a transformer or (electric obviously) motor, you can probably reason out why" I'm fairly sure you're mistaken here. A coiled extension cord has a wire running in both directions so they will cancel out unlike the windings in a transformer or a motor. (And even if that were an issue the heat dissipation issue would still also exist.)
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@PhiloSage I was responding to comments that talked about the EM field. Of course, the resistance doesn't cancel but leaving the extension cord coiled doesn't increase the resistance (though it can reduce heat dissipation).
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@hairyairey That's because a coiled cable can't dissipate heat as well as an uncoiled cable.
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@joshuaewalker "We, United States, get a single phase at the residential level of 240 volts. Throughout most of the home only 120 volts are used. We use 240 volts on dedicated circuits for water heaters, ovens, clothes dryers, HVAC systems, and electric car chargers." I think the point was the following. In the US the voltage of a single phase relative to neutral is 120V but you can also use two live wires with opposite phases to get 240V when you need a higher voltage. Similarly in Europe, the voltage of a single phase relative to neutral is 230V but you can also get 400V if you use two live wires with phases 120° apart if you need a higher voltage. This isn't like using a 3-phase motor because it's not using all the 3 phases. It's just using 2 of the phases for a higher voltage. (I agree that you probably don't need all 3 phases at home for any appliance.)
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@Jdbye "I always thought it was because a coil of wire is essentially an electromagnet and current passed through it will cause a magnetic field" This is not a huge issue because in a coiled extension cord you have wires running in both directions meaning they mostly cancel out.
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@reasonsvoice8554 Eddy currents have nothing to do with it.
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@reasonsvoice8554 In a coiled cable you have a wire running in both directions so they will cancel out. That's not the case for a coil in an induction heater.
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@reasonsvoice8554 "It doesn't have to be coiled. Magnetic fields will be created as long as you have a current through a wire." Yes, but I was responding to comments about why it says on cables to uncoil them for use. It's about heat dissipation. "Coiling may make the field strength stronger." But it doesn't in this case because the cable has two wires running in opposite directions.
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@joshuaewalker The split phase basically becomes two phases that are 180° apart when taken relative to the neutral that's taken from the middle. There's no functional difference to 2-phase power from the consumer's point of view. But if you still don't accept my wording forget this and let me rephrase what I said. In the US, you get 120V when you use a live wire and a neutral wire but you can get 240V if you use two live wires. In Europe, you get 230V if you use a live wire and a neutral wire but you can get 400V if you use two live wires (that are in a different phase). The latter isn't really using 3-phase power because it's only using 2 of the 3 phases (for a higher voltage). I think this is what the earlier comments were referring to, not using 3-phase power at home.
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That's not a bad solution.
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@joshuaewalker I meant it's 120V relative to the neutral wire.
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@joshuaewalker "it is not functionally the same as "two phase power"" What's the functional difference then? I maintain that there is none. This doesn't matter anyway since in my previous comment I provided an alternative wording that doesn't use the word "phase" (when referring to the US) so that should make it clear what I meant. "So, when we need 240 volts we do not combine those two separate legs we simply use the normal 240 volt single phase that is coming into the house" Those two are the same thing. You can't combine those two in a way that would be different from using the whole 240V phase.
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@joshuaewalker "I think we're actually on the same page so I'm not sure where the argument is anymore." It seems to me what we argued about was wording but that's not what my original reply to you was about. In your comment responding to a comment by VorpalGun (which mentioned 3-phase power) you wrote: "Frankly, other than 3-phase motors, I don't see where having 3-phase power would ever be needed or useful at the residential level." Here's my reply: In the US, you get 120V between a live and a neutral wire but you can get 240V between two live wires (disagreement causing words avoided in here). In Europe, you get 230V between a live and a neutral wire but you can get 400V between two live wires (of different phases of 3-phase power). I think this higher (400V) voltage one can get is why he mentioned 3-phase power rather than "really" using 3-phase power (i.e. using all 3 phases in an appliance).
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@joshuaewalker I'm just speculating here but maybe they use all three phases because it might be easier to just wire all three phases to the device if needs more than one phase and it doesn't have to use normal outlets or maybe taking in all the phases results in a more balanced load for all the phases. Obviously, at least resistive heating elements don't need all 3 phases in the same way as some electric motors. I was curious and I checked my breaker table and the stovetop seems to have a 3-pole breaker so it's presumably taking all 3 phases but I suspect none of the individual hot plates uses all 3 phases because I have an induction stovetop I'm not sure how that could work. Also, at least my washing machine is plugged into a normal outlet so it's using just a single phase and 230V. It would sound a bit weird to me if a consumer-grade washing machine would require 3-phase power though I can't be sure that it doesn't happen somewhere.
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@larsalfredhenrikstahlin8012 "You should be able to plug un-grounded things into grounded outlets." Monkeh wasn't complaining about being able to plug ungrounded things into grounded outlets but rather about being able to plug grounded things into ungrounded outlets.
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@Monkeh616 "CEE 7/2 ungrounded plugs cannot be inserted into 7/3 or 7/5 grounded outlets." But that problem probably isn't widespread. I think CEE 7/2 is quite rare and unearthed devices are more likely to use CEE 7/17 or Europlug which do fit into those outlets. However, it might be a safety issue if e.g. CEE 7/4 plug fits into some unearthed socket like CEE 7/1. Thought this was what you were complaining about in your first comment in this thread and if so I agree.
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@vurpo7080 "Schuko, the one used in most of Europe, has basically all the benefits of the UK plug" Schuko lacks the fuse in the plug which the UK plug has.
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That doesn't make sense. Firstly, the cable has a wire going in both directions so there's no net inductance. Secondly, even if there were it would increase heating.
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Coming back to the "The US electrical system is not 120 V" video, I wonder if would make sense for Europe to similarly start using split-phase instead of 3-phase at homes but with a higher voltage. As mentioned in the video the US uses 120V/240V split-phase power. Europe uses 230V/400V 3-phase power so the higher voltage one can get is only about 1.7 times higher than the voltage of a single phase instead of 2 times higher. With split-phase power, the voltage could be 200V/400V so that appliances requiring higher voltage could still get that 400V but the voltage of a single phase relative to neutral would be lower making it safer. Alternatively, if a higher voltage is seen as useful the voltage could be 230V/460V so that power-hungry appliances could get a higher voltage without increasing the voltage of a single phase. Or possibly the voltage could be chosen to be intermediate between these two.
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