back to article It's US vs Europe as world e-car plug standard race nears end

It looks like the US, Europe and several of the world's major car manufacturers are set to agree on a standard power connector for plug-in e-cars. Or rather two standards: one for the new world, one for the old. Due to be unveiled at a Hanover technology fair on Monday by German energy company RWE, the Euro plug uses three …

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  1. Dabooka
    Boffin

    I'm no spark, but....

    Surely a single phase only system is kind of building in obsolesence with no room for improved capacity?

    I'll be happy for some input into why it's preferable to multi phase, I just can't think why you'd do that form the start.

  2. Sam York

    What a waste of R&D and effort in general

    What's wrong with IEC 60309 (aka Cee form)?

    Support for single and three phase, will easily handle the voltage, and IP rated. Oh, and someone's already gone to the trouble of designing them.

  3. Ian Stephenson
    Thumb Up

    Travel adaptor?

    Should be fairly easy to make an adaptor to plug a Eu car into a US charger, maybe not quite so simple the other way round.

    Regardless, The cable needs to be lockable at BOTH ends. So no passing chav can swipe your cable, or unplug your car when it's charging at an outdoor point.

    Even just adding shackle points to both the plug and the socket will be adequate, decent padlocks are fairly cheap.

  4. Code Monkey

    Willy-waving

    OK I really don't get this. Surely there can't be much between the 2 standards technically. So is this just down to willy-waving between the 2 camps?

  5. Anonymous Coward
    Anonymous Coward

    Why?

    Why limit yourself to single phase charging?

  6. Simon B
    Flame

    USA different than the world again ... nothing new there!

    USA HAS to be different as per usual, or have I got the wrong end of the plug .. BZZZTTTTTT!

  7. Anonymous Coward
    Anonymous Coward

    Err...

    400v, but how many amps? Surely that is fairly important?

    Also the phase to phase voltage in the UK is 415V, +/- tollerance, this is within the phase to phase voltage range for the rest of the EU.

    I tend to agree with the above commentor cee-form would be a candidate, rugged, splash proof, available in 110v, 240v and 415v.

    Finally - why would we want the same tech as the US who have a different voltage and frequency for their power supply?

  8. Anonymous Coward
    Anonymous Coward

    Get 'er done

    Standard American practice: get it done in the simplest, cheapest way to the lowest bidder. Hang the quality.

    Mind you, a standard plug socket would be nice when taking your travel radio abroad but the number of cars that seem to swap regularly between Europe and the US must be pretty minimal.

  9. Andy Mc

    400v?

    but UK 3-phase is 415v, so a 400v rated limit means it won't be possible to directly connect to a standard 3-phase supply. bonkers.... oh, but I s'pose we're meant to have 230v single-phase over here now, which would work - shame I've never seen it below 245v round these parts....

  10. Anonymous Coward
    Anonymous Coward

    it's possibly due

    to america having a near third world attitudude to it's power supply, whereas the european systems are (generally) slightly more robust

  11. Anonymous Coward
    Stop

    @Sam York

    Yes why have one standard socket when you can choose from two dozen incompatible ones.

    http://en.wikipedia.org/wiki/IEC_60309

  12. TeeCee Gold badge

    Re: IEC 60309

    If I were to take a bet, I'd say that it was because yer IEC plugs are designed to be used by someone with a modicum of common sense, whereas yer 'leccy car recharge plugs are designed to be used by the sort of pillock who wonders how much compensation they'll be paid if they stick their fingers in the socket*.

    I'll bet there's an additional signal channel in both of these somewhere to ensure that nothing whatsoever goes live until handshaking / self test is completed (i.e. it's actually got a car on the other end of the lead) and ensures that the power is cut as soon as the signal is compromised.

    *Never underestimate the stupidity of the public. Especially when the legal system has a habit of rewarding people for doing something mind-numbingly stupid.

  13. Eddy Ito
    Pirate

    "Power ports"

    I say force them to use the same damn thing they have stuck us with. Yes, I'm referring to the good old cigar lighter adapter. If they can't come up with a decent power plug for powering accessories, how do they figure they are going to do any better with a charging port? Seriously, if they won't give us an ashtray and lighter why make us suffer with a "power port" that requires terribly huge adapters held in by spring loaded grounding contacts and placed at the end of the shifter throw at third gear?

    So how long will it take to charge the batteries at 12 VDC and 10 A?

    Oh Sam York, IEC won't cut it since it's probably cheaper, easier and better than anything SAE could come up with. Besides, SAE didn't come up with it. I suppose we should just be glad they aren't using a trailer light plug.

  14. M7S

    What about the ones already in use?

    I'm going to try to forestall ridicule by accepting that this might not meet the needs for full leccy cars, but most larger emergency vehicles (ambulances, Trumpton etc) in the UK have a 240v input called Auto Eject.

    This power can be used for either or both charging the vehicle batteries via an onboard transformer or as a "shoreline" to provide mains power to onboard systems from a more efficient source (mains, generator etc) when stationary on duty, for such things as computers and other control equipment, catering etc. They do 15 and 30A versions at 240v AC and other voltages as well. If the US is going down the single phase route, it might be nice if they used something already developed as ironically this is an American product.

  15. The Cube
    Flame

    Typical bloody Americans

    Have to have their own, half baked crappy 'standard' instead of use what the rest of the world has agreed on. Of course they won't come to their senses, history tells us this very clearly.

    The americans rejected;

    Working television for NTSC (Never Twice the Same Colo[u]r)

    Decent mobile services (GSM / PCN) and are still suffering

    Proper voltages and power delivery (230/240V) and have to have noisy and inefficient transformers everywhere as well as two different voltages in their homes since realising that you can't run an electric oven on 110V.

    If it wasn't invented in America (or stolen by an American after being invented elsewhere) they are not interested, let them rot in a technology cul de sac of their own making. Maybe if their leccy cars won't charge at a decent rate they will have to get their fat asses out of them and waddle to the fast food outlet on their tubby little legs, getting some exercise in the process.

  16. GrahamT
    Boffin

    Something not quite right...

    The "single phase" US system is said to be 240 Volt. US domestic mains is 110 Volt, European domestic mains is 230V. Three-phase is sqrt(3) x single phase voltage, i.e. 190 Volts and 398 ("up to 400") Volts respectively.

    The figures for the European system seem to fit, but it seems odd that the US seems to use a system that needs a step-up transformer (so reducing output current) when one might not be needed for three phase.

    I think we don't know enough about the US system to be sure what system they are using. We can be sure though, that the US system will take longer to charge or will need much thicker cables and contacts than the European system if the voltage is only half the European version's.

    Half the voltage means double the current for the same power, which leads to 4 times the losses in the system (proportional to the square of the current)

  17. Anonymous Coward
    Anonymous Coward

    Surely...

    USB charging is the only way to go? ;)

  18. Anonymous Coward
    IT Angle

    Re: Why?

    It's been a while since I had anything to do with this stuff, but I seem to remember that Americans don't do 3 phase - not at the domestic end of the distribution network anyway.

    So to answer your question, it's 'cos they have to!

  19. Peter Ford

    Standards across the Atlantic

    It would be perfectly normal for our American friends to adopt their own standards. Just try sailing across the Atlantic: do I go to port or starboard of that red mark? Depends if you're in American waters or the rest of the world...

  20. This post has been deleted by its author

  21. Steve
    Stop

    FFS another format war?

    Why can't they just agree?

    IEC 60309 is fine, are they afraid someone might plug in and use the power for sommit else? That'll happen eventually anyway,,,

    Locking could be achieved by having the socket cover/flap designed to enclose the plug and lock, easy peasy...

  22. A J Stiles
    Coat

    @ Sam York

    What's wrong with the IEC 60309 connector is that, being an established standard, there's no way to patent it, form a cross-licencing cartel and block any new players from entering the market by charging outrageous royalties.

    Or am I getting cynical in my old age?

  23. spam

    Hmm

    240v 70A maximum - an energy transfer rate equivalent to less than 2l of petrol per hour. What is the relative efficiency of battery + electric motor combination compared to IC engines? x 3? Even so these charging stations are like petrol pumps with hypodermic needles instead of nozzles.

    Just an indication of the true crapness of leccy tech.

    And what's all the crap about phases? Batteries are DC, what is the point of lugging battery charging circuits around with the car when they could be built into charging stations? What other portable equipment plugs directly into AC mains for charging?

  24. Anonymous Coward
    Anonymous Coward

    Tax,

    so they dont want it compatible with an extension cable flung out the window?

    electricity for cars now with added taxation

  25. Anonymous Coward
    Anonymous Coward

    IT angle...

    It's not just about voltage and phase.

    There is the small question of control systems and energy management. There needs to be a data interchange format agreed also if optimisation of the energy grid using plugged in vehicles is going to happen. The charge state and anticipated demand at each end needs to be communicated if the optimisation algorithms are going to work efficiently.

    There's no point in using cars to store power and feed it back to the house in the evening if it can't tell you that it needs to have X amount of charge available because the driver habitually uses it to go and pick up the kids from Scouts at 8:30pm on a Tuesday and doesn't want to find it nearly flat because it's all been used in the home.

    Adding a data over power lines protocol could be good for this, or else wireless network. Still needs to be in the standards though.

  26. Anonymous Coward
    Alert

    Sparky Willy Waving...

    If only monkeys could read. they would have noticed one is a 400V three Phase connector the other is 240V Single Phase... surely there is a huge difference.. well there will be when the rest of us are fast charging at the filling station while having a coffee and you are booking a room for the night!

    Its a Bright spark if you want to sell an upgrade later.. why sell one product when you can release 5 slightly improved versions over 5 years and make 5 times the Profit! Thats Business! - Customers Must DEMAND not to be ripped off!

  27. Anonymous Coward
    Unhappy

    3-phase not available in most of US

    99.99% of US homeowners (whom i would presume to be the target market in the US) will have 120 AC and 240 AC; but only single phase. Most don't have access to 3-phase unless there are two transformers (farms and businesses will have this most likely). That's not to say it can't be done; just don't expect that JoeBob will be getting a converter along with his new 'leccy-mo-bile. Furthermore, putting in a 70 amp circuit is going to be another deal breaker for most folks.

    A typical "electric" home with a standard hot water heater will have a 30-40 amp circuit; 30-40 amp for stove, maybe 80 amp if they use "instant-on" hot water. Unlikely they will have open slots in their breaker box. Most homes under-breakered as it is in an attempt to cut costs.

  28. /\/\j17

    Non-Issue?

    Isn't this really a non-issue? I mean, we aren't talking about a laptop or mobile phone that one could expect to move readily between the US/rest of the world are we (assuming Canada follow the US lead as usual).

    Exactly how many cars are we looking at that will actually move back and forth across the Atlantic/Pacific? France to Germany, etc - yes, but they would both use the rest-of-the-world standard.

  29. Peter Simpson
    Joke

    @TeeCee

    "*Never underestimate the stupidity of the public. Especially when the legal system has a habit of rewarding people for doing something mind-numbingly stupid."

    ...Not if Darwin rewards them first!

  30. Fab De Marco

    What is the point?

    America already has different domestic plugs to Europe and UK has a different one still. The steering wheel is already on the wrong side.

    Exactly how many cars get imported from US to Europe and Vice versa? The only car's I imagine are old style big Block V8's that are deemed "Classic Cars"

    So you can't jump on a boat and use your car cross atlantic. Who cares?! Don't do it!

  31. Martin Silver badge

    So I'll need an adaptor then

    If I decide to take my electric car with me the US as hand baggage?

  32. Eddy Ito
    Black Helicopters

    In all seriousness

    I'm sure "the standard" will come with its own metering system that tells the gubbermint just how many joules are being put into the car. After all, the gub has to figure some way to replace the money lost on fuel taxes. The question is, how long before people bodge together "cheater" cables to bypass the tax?

  33. Herby

    Three phase in the USA?

    Well, we don't have that at our homes. Sorry. We have these nice little plugs that supply 120 volts to our electric devices and those work quite nicely. Our lights and TVs don't flicker either being that they are at the proper frequency of 60Hz, not some french idealism frequency.

    Sure we have 240 volts for those items that slop up the amps (like kitchen ranges), but those are mostly wired in place.

    As for three phase, even here there are two standards, 120-208 'Y' three phase, and 240 'Delta' three phase, where there is a "hot leg" that is 208 bolts above the neutral, which is actually the center tap of the 120-0-120 size. And yes, I've worked with both of them. Sure three phase is nice to have if you are making DC for the battery, but if you don't have it, why bother. The problem is that when you make DC from the mains, you don't conduct over the entire cycle (power factor stuff), and the utilities don't like that. Three phase makes it a bit easier, but it is still a problem. There will always be incompatibilities in any system, and as was said before the "refueling rate" is terrible with electric means.

    Electric cars are probably a passing fad anyway, so let the bickering begin. By the time it is all done, we won't need it.

  34. P. Lee
    Coat

    re: Tax

    Won't you think of the children?

    How's the government going to pay for schools and hospitals if you're only paying domestic electricity rates to fuel your car?

    How many petrol stations will go out of business and families be made destitute because of your "saving the environment" policies?

    #1 rule: disruption of current activities is not welcome.

  35. Ken Hagan Gold badge
    Unhappy

    Wake me up when one or other goes bust...

    Like VHS/Beta or HD/Blu-ray or USB/Firewire or...

    As code monkey says, this is just another example of multi-national willy waving. The response of the average consumer will be to defer purchase until one or other standard "wins". Who loses? Well that would be the twats who thought that a battery charger was so unbelievably important that they just *couldn't* tolerate the other guys' design.

    Congrats, you plonkers, you've just put electric cars back five years. Still, Gordon will be pleased, since presumably he won't have to pay out much cash under his £5000 per car scheme.

  36. Filippo Silver badge

    oh no!

    Gah, a format war on e-car recharging is exactly what we *don't* need. I hope the American proposal dies quickly - nothing against the nationality, but limiting the charger to single-phase sounds like a terrible idea.

    Okay, most homes don't and can't have three-phase, but all industrial locations do, including existing gas stations. If the cars can take three-phase, then setting up "charge stations" in a wide variety of places becomes really cheap. You could three-phase charge your car at the hotel, at the restaurant, or at your workplace; any of those places could put a small surcharge on the cost of the juice and make a handy profit.

    As for why the existing IEC standard isn't used, I guess it's because a car charger needs to be a lot more idiot-proof. You need to design it so that the user can't get hurt even if he's trying to.

  37. Jacob Lipman

    @Billy

    "It's been a while since I had anything to do with this stuff, but I seem to remember that Americans don't do 3 phase - not at the domestic end of the distribution network anyway."

    This is, for the most part, true. My local power company quoted me about $50,000 to have 3-phase power run to my home (wanted it to run a plasma cutter. Oh well.) It would still make sense to enable the system for 3-phase, to allow for mor efficient charging in commercial/industrial settings. It would make good commercial sense, as well. Charge your car slowly at home for "free," or pay X amount at the recharger to top off quickly. People are willing to pay for convenience.

  38. Lennart Sorensen
    Go

    Single phase just makes sense worldwide.

    The only universal choice seems to be single phase at about 230V or so.

    Europe has that voltage on one phase, with 3 phases available at 120 degrees between them.

    North America has 2 phases with 180 degrees between then at 110V or so per phase, giving effectively 220V between the two phases if you ignore neutral as lots of 220V equipment in north America does (like ovens).

    So by going for single phase 220-230V or so, you can run either on one phase in Europe or between two phases in north America, at least anywhere that has residential style two phase power. No residential area of north America will have 3 phase power available. It just doesn't happen. If you can get 30A or so at 230V, that seems like a decent start. Might even be able to get away with 50A, although many houses in north America only have a total of 100A service to the house.

  39. hj

    just a matter of time..

    "According to reports from GM, which sponsors the J1772 task force, that standard has received thumb-ips from Chrysler, Ford, Toyota, Honda, Nissan and Tesla"

    Since Ford and Chrysler will be gone in a year and Tesla is not there yet, the japanese will not mind to use the European standard. Or just build two different cars. Somehow i think Opel/Vauxhall will use the european standard too.

  40. dervheid
    Stop

    So, they can't even decide on...

    one global standard charge point/connector/voltage.

    What a surprise.

    NOT!

    Which fades nicely into spam's question;

    "what is the point of lugging battery charging circuits around with the car when they could be built into charging stations?"

    Well, if they can't decide on a "universal connection", they sure as shit aren't going to be able to agree on ANY sort of *standard* types for battery packs to facilitate the 'quick-swap' recharge station to replace the filling station, now are they.

    No *standard* batteries - no *standard* charging equipment - every vehicle needs an on-board charge controller.

    Those are the real reasons that 'leccy cars will take a very, very long time to get established, if they ever do.

  41. This post has been deleted by its author

  42. Stewart Haywood
    Boffin

    @Something not quite right...

    In the US the HV distribution is generally a delta system. Now, to get the LV domestic supply they use an open delta system. To do this, you get two single phase transformers and connect one between red and blue phases and the other between blue and yellow. On the LV side, you connect one end of one secondary winding to one end of the other. You can now get 120v between the wire that connects both transformers and the other end of one of the transformer windings. You can get about 210v by going between the other two wires on the ends of the secondary windings.

    Now, if you only want the single 120v, you only need one transformer. Very often one transormer is larger than the other because it will be used in oproviding both the 120v and the 210v.

    This is a nasty but cheap system. The point that connects the two secondary windings is usually grounded. When you look at the two legs of the 210v supply they may be at different voltages with respect to ground and voltage regulation in general is crap.

    You can get propper 3 phase but it is going to cost you 50% more.

  43. Stephen Bungay

    Data Interchange over power lines...

    It's called ethernet over power and the protocol is TCPIP. Using the car as a resource to power the house is putting the cart before the horse, instead use the house as a resource to fuel the car.

    Regarding the connector at the end of the wire, it doesn't care what voltage and current flows through it just so long as it doesn't get driven beyond it's design capacity. One global standard makes perfect sense, I don't care what the standard is, just so long as there is one.

    Now, having said all this I think plug-ins are NOT the solution... batteries are

    * toxic

    * heavy

    * slow to recharge

    * costly to make

    * costly to replace

    * difficult to decommission/recycle

    * perform poorly in cold weather

    And the list goes on, so the fewer of these we use the better.

  44. Hardcastle
    Flame

    @ The Cube...

    If it wasn't for the Americans in WWII, you would be sprechen sie Deutsche and saying "Sieg Heil".

    That said, it isn't just the US who prefers to maintain their own standards compared to the EU, and therefore assure that the "One World Order" doesn't happen. The UK also maintains many standards of their own that also differ from the EU. Better? Worse? It doesn't matter. It's what we're used to in the way of measurements, no matter which side of the Atlantic you're from. A good chunk of US standards originated from England, such as the inch, mile, acre, etc. And, neither of us are spending Euros either... We have stuck with the Dollar, and the UK prefers those Pounds Sterling.

    As for the plug standard, I would prefer a 3-phase solution in the long run, as this would mean that smaller wires would be needed, and a loss reduction would be realized. Short term, however, as was noted earlier, a 220V standard would be needed, as this is what feeds the residential districts. However, if the infrastructure was revamped for the addition of a 3-phase outlet for the garage (Business districts already have 3-phase wiring available) then the long term goal of a 3-phase solution would be practical (440V in this case). But, until then, a 220V solution would mean quicker adoption, as this can be used with the existing infrastructure in the US. Then, as 3-phase becomes accessible to the residences, the 440V solution could be more readily adopted.

  45. Bounty

    ok it's settled then

    220v charge it overnight or whenever you can. If you need a quick re-fill, buy some gas.

  46. Charles Manning

    The connector isn't so important

    Standardizing the voltage and current are far more important because otherwise if you drive up to the wrong voltage and plug the thing in you will get poor results (no charge, fire, whatever).

    Connector wars are easy to rectify with adapter cables like the power -to-SATA-power cable or the things you buy when traveling overseas.

  47. Anonymous Coward
    Anonymous Coward

    3 prongs is not a good 3-phase solution

    'Cause it doesn't provide any grounding. And if you really did it in a real petrol station sparks would fly just from static electricity. It would work only for 3-phase delta wired distribution which is pretty expensive to run in US over the "current" single phase (aka two phase) three wire (2 hot, 1 neutral) drops between the pole pig ( the two-part transformer referenced above) and the house. The J1772 drawing (assuming it is right), has 4 prongs showing and would support 3-phase delta or 3-phase wye with that long ground pin that makes contact drawing off static and safing the car apparatus before the hots do. Would suspect that EU standards committees will want to have more that 3 prongs if 3-phase is expected.

    Of course 3-prongs is what is on the common US 115V/230V plugs which could work in EU also. Does the UK get standard plugs on their appliances yet?

    And there are no real problems with making a car charge controller that can handle 100-450 Volts (100 being a typical Japanese voltage) and have it control how much current gets drawn from checking out the voltage and AC frequency on the hot plugs. (Did you know that Japan is reported to have 50Hz service on one part of the country and 60Hz in others?

    Add another 8 cent timer chip to the onboard or household power sequencer controller and you could program it to charge only at 0000-0500 hours when there would be more excess capacity.

  48. JC

    Relax Fellows

    The charging system is modular, it's really quite irrelevant if there are two plugs. Note there are often more than one seat color, engine, and myriad other options on a car. The thing of primary importance is that within a region using the same charging standard, plugs on all vehicles in that region are the same.

  49. Argus Tuft
    Paris Hilton

    bugger the connector

    what's important is how long is the lead. And how do I stop it getting tangled up around the lamp posts while i'm driving??

  50. hugo tyson
    Flame

    Sprechen sie Deutsch? Russki?

    If it wasn't for the British in WWII, the USA would have had to wage the Nuclear-armed Cold War against either a) The Third Reich, controlling all Europe and Russia and N Africa, or b) The USSR controlling all Europe, Russia and N Africa. With all the British and German scientists you can think of in either case. It would have been... different...

    Seriously and on-topic, it looks to me like the USA is approaching the issue assuming most people charge up at home overnight, using (extant) private infrastructure, whereas Europe/Japan is assuming most people charge up whilst parked at work/shopping centre/motorway service station ie. using (new) public or shared corporate or subsidized infrastructure. Not least 'cos the Old World has on-street or shared parking for many many people rather than a private garage each. It also kinda matches the different approach to public services in the two worlds.

  51. Wize

    Padlocked cable

    You don't want to padlock the cable to the car and the charging post. What happens when someone drives off forgetting about it? We've seen the pics from petrol stations.

    And there is no chance I'll be able to get parked near one. I park in the street as I have a flat. Its difficult enough finding a spot big enough for a car when some idiots like parking one car in the middle of two spaces because they cant park properly. When there is a space, you have to watch for trees, lamp posts and wheely bins blocking your door before you park before they put on some charging posts.

    Stick these things in and you'd either need to space them along every street in the UK at half car lengths or you'd risk not being able to park at one.

    If I'm driving across the UK and run low on juice, I fill up in minutes with petrol. I'd have to plan a route in advance with a hotel at the right distance down which has charging posts in its carpark.

    Plugging in cars to charge them is an impractical idea.

  52. Alfonso Vespucci

    re. tax

    They won't bother to tax the leccy, they'll just introduce comprehensive road charging.

  53. John Smith Gold badge
    Thumb Up

    Its a money thing

    Whenever this comes up one side goes for the cheap limited option the other side goes for something better with a longer life expectancy.

    The US thing sounds like its domestic only. There is no high rate fast charge option which presumably an electric filling station (super-capacitor array, underground flywheel, gas turbine) could offer.

    Of course if they had gone with IEC 60309 (or agreed that an extension of that standard would sort them out) things would have gone a lot further.

    However this is a good thing in principle. People are thinking infrastructure. Unbundling charging from buying an EV. Potential competition.

    The agreement may not be perfect. But getting an agreement to begin with is a start. Cautious thumbs up.

  54. GrahamT
    Boffin

    To all those saying US doesn't have three phase to the house...

    But it seems you have two of the three phases (240? volt for cookers) already! In Europe we use the normal single phase 220-240V with thicker cable and a bigger fuse for cookers. We therefore only have single phase to the house, but the substation (3phase) transformer has a Y wound secondary with blocks of houses fed from each phase-to-ground to balance the load and stop the centre tap earth/ground from wondering too far from 0V.

    Kerbside charging stations could, therefore pick up all three phases from the underground cables. I assume it is similar in the US. It would be engineering stupity to put the whole neighbourhood on a single phase and ignore the other two. (The distribution networks are always 3 phase, but usually delta with no ground, hence the use of delta-Y transformers in the substation in Europe and America to provide a 0V centre tap)

    A three phase charging system at least gives the option of using (domestic) single phase for "trickle" charging. Designing for single phase removes the option of high speed commercial charging stations. Domestic supplies don't cut it for high speed charging.

  55. John Smith Gold badge
    Unhappy

    @GrahamT

    I didn't know about the septics using 2ph for their cookers. Although anyone setting such a standard as the plug should be familiar with the US 2nd level distribution network. You have to wonder, does the cost of such a plug change the price of an EV *that* much?

    That the US would not adopt a European standard is a given. Choosing such a limited and inflexible design is above and beyond the duty of fail.

  56. Anonymous Coward
    Anonymous Coward

    @GrahamT

    Predominating US distribution is 3-phase Wye into the neighborhod and to feed 4-10 households from one step-down transformer connected to just one of the phases (A, B, or C) and ground. The step-down creates two 180-degree opposite hot leads with a center-tapped neutral. Different than 120-degree shifts of real 3-phase. If one 100 Amp 7500 Volt fuse up the street blows it takes out only 1/3 of the neighborhood services by the step-downs on that phase.

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