You can bet that as soon as we can get our hands on a 277V NACS EVSE, we're going to install one! Also: If you want to go deeper down the rabbit hole, 120/240V split phase AC is 120V RMS (root mean square), not peak. The peak voltage is actually 170/340V, but for reasons that I'll let you google, we use the RMS value colloquially and act like that's actually the peak. An earlier cut of this video took a deep drive down that long road but our editing staff fell asleep so we decided to leave that on the cutting room floor.
@@olemissjim277 volt support was always iffy on Tesla vehicles. The older wall connector supported it officially, but the on board charger has over voltage protection that trips just a bit higher than 277V, so it can be flaky if your voltage is even slightly high. As far as I know, the newer Tesla wall connectors don't officially support 277V. Hopefully this changes with official support in NACS.
@@BrianCairns As I recall, there was a "Legacy" DIP switch that had to be set in order for the HPWC to accept 277 V. However, regardless of whether they were set properly, the older Tesla units were considered low quality/unreliable, so the internals were likely to need to be repaired/replaced even when operating within those specs.
@@olemissjim The older destination chargers explicitly support it, current destination chargers say 240V max so 277V support is best described as "unofficial" but Tesla has said directly that Model 3/y fully support 277V.
@@EVBuyersGuideIf my memory serves me correctly the v2 Supercharger cabinets is a stack of Model S/X onboard chargers and the cabinet input voltage is 277/480 volt three phase. So, technically it can handle 277 volts without any issues. I have to say that was quite an ingenious way to keep costs low by using what they already had by ganging them up together with a little bit of power electronics and voilà you got yourself a high power DC fast charger.
THIS is why I watch Alex on autos. No other car journalist would think about, let alone make a 14 minute video about a topic that (while somewhat niche for this platform) is such a big deal in the real world. Love the detail you go into as well
yeah. this is an excellent video. I just finished constructing a 3 phase apt building and I did not know this was an option. Tesla just has more common sense than allot of other companies. Build in 277 from the start, make all those light poles available all over America.
Love the use of a Mac SE/30 to demonstrate what uses a 120v plug 👍😆. I loved this video, thought it was really helpful as someone who understands EVs and the basics of charging but am by no means an electrician
I rarely post comments, but I really wish you were my Circuits professor when I took that class all those years ago, Alex. This was great, thank you for this explanation.
Excellent. I'm a mechanical engineer, work for hydroelectric power and just bought a new Ford Lightning. Its interesting to learn the background of why how EV charging works and how our grid works (at residential level). Anyway, great video!
Very useful. I've been peripherally involved with electrical service in my work for years and this was a good explanation of how American electrical service works and the differences between residential and electrical service. I don't think it was too deep into the weeds at all.
As a recently retired Electrical Power Generation Engineer who worked for Square D, Leviton, Cummins Power Generation, and T&B this was well explained. There is one issue that I ran across in Denver at a police/emergency station where they designed a step-down xfmr off one phase of the 480/277-volt panel to feed one charger. After the installation, they wanted six chargers. Sometimes a dedicated 480V delta to 120/240V delta EV charging xfmr is easier to balance from the main 480/277 volt panel which has a lot of 277 volt lighting loads.
You have to be careful with that stinger though. ChargePoint chargers cannot be used with the stinger phase. Probably the way they check for ground faults could end up sending the stinger to ground and not being able to handle it.
This was fun. I am an Electronics Technician and spent 20 years working on very low power DC devices used in potentially explosive environments like oil and gas facilities. Now I work for a company that does a lot of electrical safety testing so I am in the world of AC and anything from single phase 120 VAC to 3 Phase 480. It's been a (safe mentored) learning experience and interesting wrapping my brain around power delivery. Great video.
Excellent presentation, very educational and definitely not too deep. As someone who has cross shopped home and restaurant cooking appliances for my kitchen I've encountered the 208/240V conundrum. Glad to have the power differences explained so clearly.
It is typically heating elements that are more flexible that can run on either voltage, while the motor and controls that are more voltage-sensitive that run on the 120V. This comes at a cost of less power to the heating element, since it only runs at 75% of its power.
I really appreciate that final point about why a “Global” connector is not only never going to happen, it’s just a bad idea. We have totally different power systems in the US vs Europe, and what works best for the US would be awful in EU. A “universal” charging connector would be massive and wasteful.
Yep you would have to change AC multi phase standard for the entire infrastructure first before you can do a universal charger connector. No clue why you would even want to do that.
Yep you would have to change AC multi phase standard for the entire infrastructure first before you can do a universal charger connector. No clue why you would even want to do that.
I am just realizing this is probably a drag on the resale value of electric cars. You can’t just send them off to any country and sell them there, they can only be sold in a region with equivalent electrical systems
To be fair, a NACS-like connector that simply doubled the pins while making them half as big would work worldwide. In 3-phase countries, it would be wired L1+L2+L3+unused/N for all phases or L1+unused+unused+N for one phase, in split-phase it'd be L1+L1+L2+L2 (or L1+L2+unused+unused/N) for 240V or L1+unused+unused+N for 120V, on DC plus+plus+minus+minus.
@@HenryLoenwind We are lucky in the 50 HZ world to only have 2 voltages to deal with. Electricity is delivered along the street from a single remote sub-station as 3-phases at 400 volts.(+-5%) using 4 physical wires. ie. a neutral wire and 3 phase wires. The voltage from neutral to any phase is 230v. This power is sent to most homes from the street using a neutral wire and one of the phase wires giving ordinary homes a single phase at 230v. Alternate houses along the street and connected to different phases in the street to balance the load. We do not use split phase. Larger premises, or houses requiring 400v 3-phase get a neutral and all three phases. This gives them access to both 230v and 400v. This simpler approach is why NACS will not be used in the rest of the world.
I appreciate the deep dive. Not that I understood it all, but I now understand just a little bit more about single- and triple-phase power -- and have a "high-level" understanding of how /why it changes things. Thanks. Keep 'em coming.
I’ve been advocating this for years 277v is one leg of a 480v transformer. So a one 3 pole 480v 20A would have very little voltage drop, an inexpensive L1 N G to a EVSE would be 20A x 277v = 5.5kW Vs the less efficient 3p 208, so you need L1 and L2 plus G and with volt drop it’s around 201v. 20A x 201v = 4kW. So you your EV is charging at 37% faster with less loss and the transformer doesn’t have to deal with wacky L1 L2 and L2 L3 and L3 L1 balancing For cars with 32A max it's even better 32A x 201v = 6.4kW 32A x 277v = 8.9kW Or 48S Or 48A x 201v = 9.6kW 48A x 277v = 13.2kW Residential is 240v. So it's still a big improvement at 277v and no phase balance issues Saves SO much money on copper and transformers and line loss, while boosting charging time ~20% to 40% Large parking lots, like malls, apt, condos, and airports could deploy super inexpensive 20A NACS stalls at 277v and be close to the speed of their 208v 30A at dramatically lower deployment cost
This was awesome! I’ve had so much difficulty finding explanations on these topics that aren’t “dumbed down” to the point of not offering useful information. I get it that not everyone has the background to follow what you just presented but it’s frustrating when deeper dives are not posted by anyone.
I always wondered why commercial L2 chargers were at 208V but never bothered to google it. Thanks for answering that and also helping me understand why allowing 277V is a big deal! Can’t wait for everyone to switch to NACS.
In the UK most home supplies are single phase and max out at 32A so charge at 7.4kW on 230V. In some Scandinavian countries their house stock is newer and therefore have 3 phase as standard, giving them up to 22kW charging.
5:04 I assume you simplified this to make it easier to understand, but technically the 120 volts refers to the RMS voltage. The peak voltage as drawn on your graph would be √2 times higher, or 170 volts. In terms of the power delivered, 120V RMS AC delivers the same power as 120V DC (for a given current), which is why we use the RMS voltage. However, because the peak voltage is actually higher, things like wire insulation and capacitors need to be designed for the higher peak voltage.
Yes. Our original video was nearly twice as long and went down too many rabbit holes, so we re-cut it and re-filmed parts to make things simpler and easier for the average EV intender to follow. RMS was just a bridge too far
Great, simple explanation of the voltage spreads and the benefits of operating "pre-transformer" on 3-phase power! Another reason to be excited about the move to NACS!
That was a fantastic deep dive, I’ve installed 240V charger at home and required a lot of other stuff and I thought I understood North American electrical circuits now. But oh man commercial US power is very different, couldn’t take my eyes off your drawings. Good job mate!
Fantastic video. Very educational indeed. I would love to see more of these deep dives. As EE grad, I love this pivot to some nerd stuff. I had wondered about why 240V & 208V were explicitly called out on my EVSE. But never bothered to think more about it. Now I know. Thanks guys.
One easy way also to think of it is that a 480/3 vs a 208/3 has over double the power for the same amperage so you can cut you service size in at least half
More deeper dives. I’ve definitely witnessed this Split1Phase 240 vs 3Phase 480 explanation before but it never stuck. In one ear and out the other leaving me confused. You’ve got a clear, concise, effective teaching style that worked for me this time. Thank you so much.😊
One of the reasons 277V will take a bit longer is the safety factor. Heat specifically the incident energy is a squared variable. So that relatively small increase in voltage means there's a lot more heat in case of a fault. The equipment, wires, everything has to be able to safely handle the added stress.
When will we start seeing NEMA 7-15, 7-20, 7-30, & 7-50 adapters for our Tesla mobile connectors? Thanks for your peak vs RMS disclaimer, as a power nerd I was vibrating watching your presentation. The adoption of 277 charging will make large level 2 sites much cheeper and more efficient. Thanks for getting this issue into the public eye.
It's nice to watch a video on something you already understand to see if the author actually knows what he's talking about and as an electrician I can confirm, he got everything correct!
i loved this deep dive, Alex! I'm a bit of an electrical tech nerd too! used to work on emergency backup generators and transfer switches/paralleling gear.
Yea, in Canada you'll just have to make do with either a high-leg delta stepdown transformer that could give you 120/208/240V, but 347 I think was just too far outside the ~240V nominal window to logically support.
I'd really love to see a deep dive into the toyota/lexus hybrid systems. the theory of operation if you will. how both mechanical and electrical power flow etc. I saw a deep dive into the honda systems a while ago and i enjoyed that a lot.
I wonder if the 277v will be labeled. Right now with a J3400-J1772 adapter I can charge a non-tesla at a tesla brand destination charger. However what would happen if I plugged in to a 277v destination charger with a system that can only handle 240? Sparks / Fire / Nothing? All are less than ideal outcomes.
This is the exact question I, too, have. I am guessing that, currently, all Tesla destination chargers ARE 240 Volt. But how will we know if that’s not the case and what are the repercussions?
Currently "it depends". Apparently Mach Es will charge, some vehicles will give an over voltage warning, some will start charging but then have charger faults and possible damage. Exact data is hard to come by but supposedly Volt and Bolt chargers can get damaged by charging on a 277V destination charger.
@@EVBuyersGuide that is good to know. So it's a bit of russian roulette if I plug into a Tesla destination charger if I'm going to damage my vehicle or not. Problems like this are a significant part of what holds back EV adoption.
I love nerding out! 😇 Especially with a Mac SE/30 w/a Motorola 030 processor... that SE/30 was like a killer Mac IIci in a lil' box back then. 🤓 Oh wait there was a Mac IIci next to it!!! ha ha I LOVE it!!!
Wow, very interesting. I originally come from Australia and normally there a home will have single phase 240 V. However, if you install a Tesla wall connector, as you pointed out, you have to wire it three phase because of the phase load balancing requirements. The electrical system in the United States has always bamboozled me somewhat because I am so used to having a three phase environment for heavy electrical loads in a household. Great explanation Alex I learned a lot, particularly that the onboard chargers are current limited, not power limited and the difference between US Mains power delivery at a residential home as compared to a commercial property. I personally would very much like to see that in the near future on board EV chargers are all rated for at least 80 Amps, vs the current 40/48Amp, as with batteries the size of the Silverado they are not simply adequate enough to take advantage of super off peak rate time periods..
This is a difference between the standards, not the connectors. J1772 is more than capable of handling 277V, but it is not written into the standard, and thus it is not supported. It could probably be easily accomodated, but contrary to your statement, most buildings DO have 208/240V and very few non-commercial (read not a factory) buildings have 480V 3 phase service, which is what is required in order to get a 277V 2 phase power source. Certainly most apartment buildings, churches, and schools would not have 3 phase service unless they were pretty huge, and then only to power the HVAC system.
Agreed, but again, like you said, if you have that 480VAC switch panel for the HVAC right where the utilities come in, that's what you need to pull out the EV circuits. Plus, for big parking lot jobs, the utility will want to pull in new feed and 480/277 for AC charging directly for a large employee parking lot job covering a good fraction of the lot. Now they do a 208/277 service for a job like that; what a waste. 33% more copper plus the losses.
Model 3/Y and refreshed S/X can do up to 300VAC charging, even if it's not advertised. I would expect that the OBC's on most other EV's are capable of it too, but the software almost certainly doesn't support it considering the limit of J1772. But that does make me wonder if J1772 could be amended to support it. I can't imagine there's any physical limitation preventing it from handling a small increase in voltage.
I had never realised what a mess the US electrical supply is. In the UK it’s much simpler - we have either 230V single phase or 400V 3 phase (230V x 3). In the UK we get three phase in some domestic properties (I have a 3 phase 75kW into my home) but the majority are single phase. New properties are now being installed with 3 phase due to the strategic aim to move to EVs and heat pumps for home heating. European EVs typically can charge at 3.7kW, 7.2kW (16A/32A single phase), 11kW or 22kW (16/32A three phase). Not all EVs support 32A three phase so a lot of cars only support up to 11kW. I have a dual 3 phase charging post in my driveway which can handle two cars either at 3.7kW or 11kW.
Some of the Teslas here in Europe that were early builds or imported have NACS and with that I've even seen some Superchargers that have both NACS and CCS.
@@EVBuyersGuide Possibly this one as a bit of a tech tangent maybe? I'd bet there's a high overlap of tech nerds and EV enthusiasts on this channel. If not maybe the Mountain Garden channel?
Great explanation! the MAIN point is cheaper Level 2 installations but as you rightly pointed out, what will happen to existing J1772 vehicles...? For the good of the EV future, they need to start handing out these J3400 Level 2 277V EVSEs like candy. So many commercial building owners are very reluctant to install the Level 2 chargers due to cost.
Alex, really curious how this is going to play out in the Retail space as charging your car may become a perk of Walmart+ etc. Right now, the LOE (level of effort) is burdened on the on premise transformer / end user-- however, with that potentially changing, that could be the ticket to higher speed charging and widely available compatible charging stations independent of the car you drove. As for the standards themselves, are they governed by an IEEE like board for all geographical countries? Seems like a no brainer to help with moving standards forward. Great video btw! 😎
Never heard of that 3,5/3,6 kW limit in Europe. Matter of fact, most single phase vehicle/charger uses 7,4 kW (1phase 230V - 32A) But it's true that you'll find a lot of 22 kW (3phase 230V - 32A) stations in parking lots. Not so much at home, which is more commonly 7,4 kW.
Great description, however suspect the onboard vehicle charger immediately rectifies any AC power into DC, where it can use a low cost switching tranisitors (IBGTs) to control the charging. 3 phase is better for rectifing to DC since it doesn't create as ugly DC pulses. It only requires six (6) inexpensive diodes in the wall connector for an NACS (SAE J3400) to work. I've suspected the lower voltage DC support might have been planned for 3 phase and home direct DC solar charging solutions.
I once owned a 2017 Model X with the dual chargers which would charge at 72a. I found a place that had a level 2 Tesla charger on a 277v 100a breaker. The car charged at 19.9 kW. That’s what I call fast AC charging.
This is a timely topic. I suppose it's been obvious for quite a while, but it's now becoming even more obvious, that what we'll be needing is level 2 charging everywhere.
Thank you for the explanation of how to get how many Kw an hour you can charge at. I was curious how that worked and had wondered how you figured that number out and now I know.
Here is a dumb question I had years ago. Why won’t public EVSE makers such as ChargePoint include an auto transformer kit to be installed at the base of the charger pedestal that would reduce voltage by 40 bringing 277 down closer to 240 range? seems like an easy fix, if such a transformer would fit. That way we wouldn’t have to install 112.5 kVA transformer for every 13 charging stalls. This, as you can, imagine, is a huge expense and why it is challenging in North America to adopt chargers when we have 4 different three phase AC systems, while Europe just has 1
Not quite right, in Europe, 32A at 230V (7kW) is available in most places, such as wired-in home EVSEs. Only if you resort to “emergency” 3 pin plug charging will you be limited to 3 or 4kW. In public and workplace settings you will always get 3 phase, which means 22kW. Yes, my Tesla charges at 22kW. At home. Even 44kW is possible by the standard. And most new homes get 3 phase nowadays. All for one more conductor in the connector and cable. A bit short sighted of North America to adopt the NACS/Tesla connector which can only ever support single phase.
One of our biggest problems was never allowing 3 phase to residential. 208 3 phase would of allowed evse's to be made 208 like they are in europe, and would of allowed the very easy scaling of 480v 3 phase and that would fix all these problems. Personally i see 240v split phase becoming a problem in the future and the lack of residential 3 phase leading to issues
The lack of residential 3 phase isn't really an issue. While 3 phase charging could have reduced conductor sizes, it's not an enormous difference and the cost of conversion would be huge. The main rationale for split phase power is that the voltage potential is lower so less risk of arcing and higher safety margins.
@EVBuyersGuide as we move into a world of electric utilities like hot water, stoves, heating, and clothes dryers, electrical usage is going up in the average home drastically. The single phase network was never designed to support this volume of high demand utilities. I bought a house with a 50A service in 2023. That's it. That's all it needed to supply everything for the whole house. I had to upgrade it because my ev ate 30A and it did trip the main, but prior to that ev it wasn't needed because nothings electric. A hot water heater is 20A, a stove is 40-50A, a dryer is around 20A, I saw an electric heating system that was 100A for a 2500sqft house! Yes heat pumps would help but not when it's 5 degrees out. 208 3 phase would cut down current by a third, and maybe we wouldn't need 350A mains on homes today for high electrical houses
We have historical analogies we can look back on. When air conditioning first hit the market there were the same concerns and the utilities and the grid just adapted. If everyone replaced their car with an EV in the same year this would be an issue, but the gradual replacement is less likely to be an issue. It is entirely possible to live with an EV and charge slower. For instance I (Alex) live off the grid and my inverters max out at 19 kW continuous so the answer is: charge slower. At 3kW we're still talking a solid 30kWh charge overnight which is 60-120 miles of driving depending on the vehicle, well over the average daily commute.
@@EVBuyersGuide I live in nyc and air conditioners certainly cause problems for the grid during the summer. There are notable brownouts throughout the whole area the hotter it gets. Thankfully most of the cities infrastructure is still built around gas and fuel rather than electric outside of it, or the grid would implode. EV charging has already been documented to be an issue, and charging restrictions have already been implemented by local municipalities due to how hard they're hitting the grid.
According to the utilities I have spoken with, the electric vehicles are fairly easy to integrate because of several factors. The demand is fairly constant. Regardless of the weather, air-conditioning based blackouts are harder to cover with grid improvements because they occur relatively infrequently compared to the average load.. an electric vehicle on the other hand would cause the daily load to increase steadily overtime, allowing a profitable case for expansion of the grid. In addition to that, offer smart, charging profiles, and generally speaking charging reaches its peak late in the day, after air-conditioning demand has dropped
The reason it’s single please and not two phase is because only one of the three phases from the utility feeders along with the neutral runs to the transformer.
i'm surprised no one has mentioned the very common three phase Wye transformers that deliver 120v/208v without the need for a secondary transformer. This works great for EVSE's and does not require compatibility with 277v.
At first i was just wondering why not just wire your three phase transformer with a wild leg, then i realized the load balance with EV chargers all being on that phase would not be optimal to put it nicely
OKAY I edited before posting... 🤣😂 . . . While we're at it why not use 480 AC for EV charging ? Anything under 600v is basically the same .... Nevermind... I googled it 480v is 600v+ so that's not going to work. Because once you go over 600v you need 1k rating and a tons of testing and the insulation will be bigger than the wire 🤣😂 Nice and concise covering the AC voltage waves. 👍
You can bet that as soon as we can get our hands on a 277V NACS EVSE, we're going to install one! Also: If you want to go deeper down the rabbit hole, 120/240V split phase AC is 120V RMS (root mean square), not peak. The peak voltage is actually 170/340V, but for reasons that I'll let you google, we use the RMS value colloquially and act like that's actually the peak. An earlier cut of this video took a deep drive down that long road but our editing staff fell asleep so we decided to leave that on the cutting room floor.
Tesla wall connectors ALREADY support 277v and I believe all Model3/Y and most s/x support 277
@@olemissjim277 volt support was always iffy on Tesla vehicles. The older wall connector supported it officially, but the on board charger has over voltage protection that trips just a bit higher than 277V, so it can be flaky if your voltage is even slightly high. As far as I know, the newer Tesla wall connectors don't officially support 277V.
Hopefully this changes with official support in NACS.
@@BrianCairns As I recall, there was a "Legacy" DIP switch that had to be set in order for the HPWC to accept 277 V. However, regardless of whether they were set properly, the older Tesla units were considered low quality/unreliable, so the internals were likely to need to be repaired/replaced even when operating within those specs.
@@olemissjim The older destination chargers explicitly support it, current destination chargers say 240V max so 277V support is best described as "unofficial" but Tesla has said directly that Model 3/y fully support 277V.
@@EVBuyersGuideIf my memory serves me correctly the v2 Supercharger cabinets is a stack of Model S/X onboard chargers and the cabinet input voltage is 277/480 volt three phase. So, technically it can handle 277 volts without any issues.
I have to say that was quite an ingenious way to keep costs low by using what they already had by ganging them up together with a little bit of power electronics and voilà you got yourself a high power DC fast charger.
Was not expecting an electrical engineering crash course in this video. Nice job!
THIS is why I watch Alex on autos. No other car journalist would think about, let alone make a 14 minute video about a topic that (while somewhat niche for this platform) is such a big deal in the real world. Love the detail you go into as well
yeah. this is an excellent video. I just finished constructing a 3 phase apt building and I did not know this was an option. Tesla just has more common sense than allot of other companies. Build in 277 from the start, make all those light poles available all over America.
*tries to remember which videos Out of Spec Reviews and Transport Evolved have put out recently*
What is Alex on Autos? This channel has a different name.
Old arse news now. Must be a slow news day
Love the use of a Mac SE/30 to demonstrate what uses a 120v plug 👍😆. I loved this video, thought it was really helpful as someone who understands EVs and the basics of charging but am by no means an electrician
I should have used a shotgun mike to add in the floppy disk noises LOL
I rarely post comments, but I really wish you were my Circuits professor when I took that class all those years ago, Alex. This was great, thank you for this explanation.
Excellent. I'm a mechanical engineer, work for hydroelectric power and just bought a new Ford Lightning. Its interesting to learn the background of why how EV charging works and how our grid works (at residential level). Anyway, great video!
Very useful. I've been peripherally involved with electrical service in my work for years and this was a good explanation of how American electrical service works and the differences between residential and electrical service. I don't think it was too deep into the weeds at all.
As a recently retired Electrical Power Generation Engineer who worked for Square D, Leviton, Cummins Power Generation, and T&B this was well explained. There is one issue that I ran across in Denver at a police/emergency station where they designed a step-down xfmr off one phase of the 480/277-volt panel to feed one charger. After the installation, they wanted six chargers. Sometimes a dedicated 480V delta to 120/240V delta EV charging xfmr is easier to balance from the main 480/277 volt panel which has a lot of 277 volt lighting loads.
You have to be careful with that stinger though. ChargePoint chargers cannot be used with the stinger phase. Probably the way they check for ground faults could end up sending the stinger to ground and not being able to handle it.
@@patrickmay8261 I am not following your thought process
Highlight of my day is Alex validating my nerd credentials by sticking with the video. Very informative and useful, thanks!
Yay for power nerds!
This was fun. I am an Electronics Technician and spent 20 years working on very low power DC devices used in potentially explosive environments like oil and gas facilities. Now I work for a company that does a lot of electrical safety testing so I am in the world of AC and anything from single phase 120 VAC to 3 Phase 480. It's been a (safe mentored) learning experience and interesting wrapping my brain around power delivery. Great video.
You remain the best at razor sharp accurate facts. Thank you for being such a power nerd.
Excellent video. As a European viewer I’ve just learned a lot about US power grid standards.
Excellent presentation, very educational and definitely not too deep. As someone who has cross shopped home and restaurant cooking appliances for my kitchen I've encountered the 208/240V conundrum. Glad to have the power differences explained so clearly.
It is typically heating elements that are more flexible that can run on either voltage, while the motor and controls that are more voltage-sensitive that run on the 120V. This comes at a cost of less power to the heating element, since it only runs at 75% of its power.
I really appreciate that final point about why a “Global” connector is not only never going to happen, it’s just a bad idea. We have totally different power systems in the US vs Europe, and what works best for the US would be awful in EU. A “universal” charging connector would be massive and wasteful.
Yep you would have to change AC multi phase standard for the entire infrastructure first before you can do a universal charger connector. No clue why you would even want to do that.
Yep you would have to change AC multi phase standard for the entire infrastructure first before you can do a universal charger connector. No clue why you would even want to do that.
I am just realizing this is probably a drag on the resale value of electric cars. You can’t just send them off to any country and sell them there, they can only be sold in a region with equivalent electrical systems
To be fair, a NACS-like connector that simply doubled the pins while making them half as big would work worldwide. In 3-phase countries, it would be wired L1+L2+L3+unused/N for all phases or L1+unused+unused+N for one phase, in split-phase it'd be L1+L1+L2+L2 (or L1+L2+unused+unused/N) for 240V or L1+unused+unused+N for 120V, on DC plus+plus+minus+minus.
@@HenryLoenwind We are lucky in the 50 HZ world to only have 2 voltages to deal with. Electricity is delivered along the street from a single remote sub-station as 3-phases at 400 volts.(+-5%) using 4 physical wires. ie. a neutral wire and 3 phase wires. The voltage from neutral to any phase is 230v. This power is sent to most homes from the street using a neutral wire and one of the phase wires giving ordinary homes a single phase at 230v. Alternate houses along the street and connected to different phases in the street to balance the load. We do not use split phase.
Larger premises, or houses requiring 400v 3-phase get a neutral and all three phases. This gives them access to both 230v and 400v.
This simpler approach is why NACS will not be used in the rest of the world.
This is what I really appreciate about your channels, lots of "deep" facts and backgrounds, not just opinions.
I appreciate the deep dive. Not that I understood it all, but I now understand just a little bit more about single- and triple-phase power -- and have a "high-level" understanding of how /why it changes things. Thanks. Keep 'em coming.
I’ve been advocating this for years
277v is one leg of a 480v transformer. So a one 3 pole 480v 20A would have very little voltage drop, an inexpensive
L1 N G to a EVSE would be
20A x 277v = 5.5kW
Vs the less efficient 3p 208, so you need L1 and L2 plus G and with volt drop it’s around 201v.
20A x 201v = 4kW.
So you your EV is charging at 37% faster with less loss and the transformer doesn’t have to deal with wacky L1 L2 and L2 L3 and L3 L1 balancing
For cars with 32A max it's even better
32A x 201v = 6.4kW
32A x 277v = 8.9kW
Or 48S
Or
48A x 201v = 9.6kW
48A x 277v = 13.2kW
Residential is 240v. So it's still a big improvement at 277v and no phase balance issues
Saves SO much money on copper and transformers and line loss, while boosting charging time ~20% to 40%
Large parking lots, like malls, apt, condos, and airports could deploy super inexpensive 20A NACS stalls at 277v and be close to the speed of their 208v 30A at dramatically lower deployment cost
This was awesome!
I’ve had so much difficulty finding explanations on these topics that aren’t “dumbed down” to the point of not offering useful information.
I get it that not everyone has the background to follow what you just presented but it’s frustrating when deeper dives are not posted by anyone.
I always wondered why commercial L2 chargers were at 208V but never bothered to google it. Thanks for answering that and also helping me understand why allowing 277V is a big deal! Can’t wait for everyone to switch to NACS.
Great explanation! Coming from Europe I now understand more about the system in America. Thanks a lot!
In the UK most home supplies are single phase and max out at 32A so charge at 7.4kW on 230V. In some Scandinavian countries their house stock is newer and therefore have 3 phase as standard, giving them up to 22kW charging.
Most excellent deep dive!!! Never even thought 277v would be option (or even consideration) for level 2 commercial! Nice...
this was excellent. great work. agree, hope it can help expand lvl 2 which is sorely needed literally everywhere!
5:04 I assume you simplified this to make it easier to understand, but technically the 120 volts refers to the RMS voltage. The peak voltage as drawn on your graph would be √2 times higher, or 170 volts.
In terms of the power delivered, 120V RMS AC delivers the same power as 120V DC (for a given current), which is why we use the RMS voltage. However, because the peak voltage is actually higher, things like wire insulation and capacitors need to be designed for the higher peak voltage.
Yes. Our original video was nearly twice as long and went down too many rabbit holes, so we re-cut it and re-filmed parts to make things simpler and easier for the average EV intender to follow. RMS was just a bridge too far
Great, simple explanation of the voltage spreads and the benefits of operating "pre-transformer" on 3-phase power! Another reason to be excited about the move to NACS!
Oh, what a lovely SE/30 and IIci! The most beautiful classic Macintoshes ever.
That was a fantastic deep dive, I’ve installed 240V charger at home and required a lot of other stuff and I thought I understood North American electrical circuits now.
But oh man commercial US power is very different, couldn’t take my eyes off your drawings. Good job mate!
Fantastic video. Very educational indeed. I would love to see more of these deep dives. As EE grad, I love this pivot to some nerd stuff.
I had wondered about why 240V & 208V were explicitly called out on my EVSE. But never bothered to think more about it. Now I know.
Thanks guys.
One easy way also to think of it is that a 480/3 vs a 208/3 has over double the power for the same amperage so you can cut you service size in at least half
Thank you for the education. You are a standouts in your field. And I still have my SE/30 and NeXT Cube!
Great job explaining that. I think most people will completely understand this.
More deeper dives. I’ve definitely witnessed this Split1Phase 240 vs 3Phase 480 explanation before but it never stuck. In one ear and out the other leaving me confused.
You’ve got a clear, concise, effective teaching style that worked for me this time. Thank you so much.😊
LOVED the detail. Getting into the weeds is my kink.
One of the reasons 277V will take a bit longer is the safety factor. Heat specifically the incident energy is a squared variable. So that relatively small increase in voltage means there's a lot more heat in case of a fault. The equipment, wires, everything has to be able to safely handle the added stress.
You broke it down really well Alex. Great primer on why 277V is needed for the commercial side on EV charging.
When will we start seeing NEMA 7-15, 7-20, 7-30, & 7-50 adapters for our Tesla mobile connectors? Thanks for your peak vs RMS disclaimer, as a power nerd I was vibrating watching your presentation. The adoption of 277 charging will make large level 2 sites much cheeper and more efficient. Thanks for getting this issue into the public eye.
It's nice to watch a video on something you already understand to see if the author actually knows what he's talking about and as an electrician I can confirm, he got everything correct!
Learned a lot in the time of a coffee break. Thanks!
Knowing more is usually better and it is in this case. Still don’t fully understand everything, but learned a lot in this video. TY
Great explanation, really ticked all the curiosity boxes.
This was great information! Great work!
Thanks for covering this Alex, Power Geek here.
i loved this deep dive, Alex! I'm a bit of an electrical tech nerd too! used to work on emergency backup generators and transfer switches/paralleling gear.
It seems no one working on SAE J3400 talked to Canada, they use 600/347V for commercial 3-phase. Why not use the same voltage range as J3068?
Yea, in Canada you'll just have to make do with either a high-leg delta stepdown transformer that could give you 120/208/240V, but 347 I think was just too far outside the ~240V nominal window to logically support.
This was great. We are rewiring our building and parking for EV's and I wasnt aware of this difference!
I'd really love to see a deep dive into the toyota/lexus hybrid systems. the theory of operation if you will. how both mechanical and electrical power flow etc. I saw a deep dive into the honda systems a while ago and i enjoyed that a lot.
1:47 excited to see working Macintosh
This was awesome! Just as the detail started to make my eyes glass over, you brought it all home and made perfect sense to me. Great information!
I wonder if the 277v will be labeled. Right now with a J3400-J1772 adapter I can charge a non-tesla at a tesla brand destination charger. However what would happen if I plugged in to a 277v destination charger with a system that can only handle 240? Sparks / Fire / Nothing? All are less than ideal outcomes.
This is the exact question I, too, have. I am guessing that, currently, all Tesla destination chargers ARE 240 Volt. But how will we know if that’s not the case and what are the repercussions?
There are a few 277V destination chargers out there, but they are rare.
Currently "it depends". Apparently Mach Es will charge, some vehicles will give an over voltage warning, some will start charging but then have charger faults and possible damage. Exact data is hard to come by but supposedly Volt and Bolt chargers can get damaged by charging on a 277V destination charger.
@@EVBuyersGuide that is good to know. So it's a bit of russian roulette if I plug into a Tesla destination charger if I'm going to damage my vehicle or not. Problems like this are a significant part of what holds back EV adoption.
This seems to be why we have not seen adapters for destination chargers from Ford, GM, etc and possibly never will.
I love nerding out! 😇 Especially with a Mac SE/30 w/a Motorola 030 processor... that SE/30 was like a killer Mac IIci in a lil' box back then. 🤓 Oh wait there was a Mac IIci next to it!!! ha ha I LOVE it!!!
Wow, very interesting. I originally come from Australia and normally there a home will have single phase 240 V. However, if you install a Tesla wall connector, as you pointed out, you have to wire it three phase because of the phase load balancing requirements. The electrical system in the United States has always bamboozled me somewhat because I am so used to having a three phase environment for heavy electrical loads in a household. Great explanation Alex I learned a lot, particularly that the onboard chargers are current limited, not power limited and the difference between US Mains power delivery at a residential home as compared to a commercial property. I personally would very much like to see that in the near future on board EV chargers are all rated for at least 80 Amps, vs the current 40/48Amp, as with batteries the size of the Silverado they are not simply adequate enough to take advantage of super off peak rate time periods..
Great idea for a video and very well done! Homrun!
Thank you. Not too deep a dive.
32A at 208V, (ergo 3Ø) seems to be most popular at low power L2 charging stations.
277V is quite exciting since we would get 33% more pixies!
This is a difference between the standards, not the connectors. J1772 is more than capable of handling 277V, but it is not written into the standard, and thus it is not supported. It could probably be easily accomodated, but contrary to your statement, most buildings DO have 208/240V and very few non-commercial (read not a factory) buildings have 480V 3 phase service, which is what is required in order to get a 277V 2 phase power source. Certainly most apartment buildings, churches, and schools would not have 3 phase service unless they were pretty huge, and then only to power the HVAC system.
Agreed, but again, like you said, if you have that 480VAC switch panel for the HVAC right where the utilities come in, that's what you need to pull out the EV circuits. Plus, for big parking lot jobs, the utility will want to pull in new feed and 480/277 for AC charging directly for a large employee parking lot job covering a good fraction of the lot. Now they do a 208/277 service for a job like that; what a waste. 33% more copper plus the losses.
Model 3/Y and refreshed S/X can do up to 300VAC charging, even if it's not advertised. I would expect that the OBC's on most other EV's are capable of it too, but the software almost certainly doesn't support it considering the limit of J1772. But that does make me wonder if J1772 could be amended to support it. I can't imagine there's any physical limitation preventing it from handling a small increase in voltage.
Perfect level of depth, thanks!
In europe, single phase AC chargers go up to 32 amps, about 7.2kw. The plug in granny chargers are usually limited to 16 amps (3.6kw).
I had never realised what a mess the US electrical supply is. In the UK it’s much simpler - we have either 230V single phase or 400V 3 phase (230V x 3). In the UK we get three phase in some domestic properties (I have a 3 phase 75kW into my home) but the majority are single phase. New properties are now being installed with 3 phase due to the strategic aim to move to EVs and heat pumps for home heating. European EVs typically can charge at 3.7kW, 7.2kW (16A/32A single phase), 11kW or 22kW (16/32A three phase). Not all EVs support 32A three phase so a lot of cars only support up to 11kW. I have a dual 3 phase charging post in my driveway which can handle two cars either at 3.7kW or 11kW.
Some of the Teslas here in Europe that were early builds or imported have NACS and with that I've even seen some Superchargers that have both NACS and CCS.
Wow this was a fantastic explanation! I've driven an EV for the past 8 years and know a lot of nitty-gritty details but this is new to me
Alex, are you telling me on top of everything else you have a vintage Macintosh collection? If so I'd love to see a video on that!
I’m not sure which channel we would put that on?
@@EVBuyersGuide Possibly this one as a bit of a tech tangent maybe? I'd bet there's a high overlap of tech nerds and EV enthusiasts on this channel. If not maybe the Mountain Garden channel?
I love this! No one else talks about 277V being in spec now!
Nice rundown..thanks
This was great - this kind of stuff needs to be integrated into highschool curriculum.
electricity? it is.....right hand rule and all....
🙄
School teaches you how to learn. Figure it out. Shoving more factoids at kids doesn’t make them smarter.
GREAT LECTURE. Love it! I think you might be implying that we should wait 3-5 years for the new charging standard to get implemented in vehicles.
Great explanation! the MAIN point is cheaper Level 2 installations but as you rightly pointed out, what will happen to existing J1772 vehicles...? For the good of the EV future, they need to start handing out these J3400 Level 2 277V EVSEs like candy. So many commercial building owners are very reluctant to install the Level 2 chargers due to cost.
At the moment it would only benefit Tesla and could physically damage pre J3400 EVs/PHEVs. That would be a big problem. -Travis
That was fantastic. It explained a lot for me.
Awesome explanation, Alex!
Thanks! 😃
Great explanation!
Alex, really curious how this is going to play out in the Retail space as charging your car may become a perk of Walmart+ etc. Right now, the LOE (level of effort) is burdened on the on premise transformer / end user-- however, with that potentially changing, that could be the ticket to higher speed charging and widely available compatible charging stations independent of the car you drove.
As for the standards themselves, are they governed by an IEEE like board for all geographical countries? Seems like a no brainer to help with moving standards forward. Great video btw! 😎
Never heard of that 3,5/3,6 kW limit in Europe.
Matter of fact, most single phase vehicle/charger uses 7,4 kW (1phase 230V - 32A)
But it's true that you'll find a lot of 22 kW (3phase 230V - 32A) stations in parking lots. Not so much at home, which is more commonly 7,4 kW.
Great information as always!
Australia has 240 volts single phase power as standard and 415 volts three phase for special purposes like welding.
Great description, however suspect the onboard vehicle charger immediately rectifies any AC power into DC, where it can use a low cost switching tranisitors (IBGTs) to control the charging. 3 phase is better for rectifing to DC since it doesn't create as ugly DC pulses. It only requires six (6) inexpensive diodes in the wall connector for an NACS (SAE J3400) to work. I've suspected the lower voltage DC support might have been planned for 3 phase and home direct DC solar charging solutions.
I once owned a 2017 Model X with the dual chargers which would charge at 72a. I found a place that had a level 2 Tesla charger on a 277v 100a breaker. The car charged at 19.9 kW. That’s what I call fast AC charging.
This is a timely topic.
I suppose it's been obvious for quite a while, but it's now becoming even more obvious, that what we'll be needing is level 2 charging everywhere.
Excellent video Alex, thanks!
This was brilliant! Answered a lot of questions I had about single vs 3 phase power. Thank you!
Thanks. Great info
LOVE the educational information. NERDS RUN THE WORLD!!
Thank you for the explanation of how to get how many Kw an hour you can charge at. I was curious how that worked and had wondered how you figured that number out and now I know.
Great discussion. Could add delta vs. wye transformers in US related to EV charging another video.
Forget the electric cars, I want your fully restored SE/30 and IIci!
Here is a dumb question I had years ago. Why won’t public EVSE makers such as ChargePoint include an auto transformer kit to be installed at the base of the charger pedestal that would reduce voltage by 40 bringing 277 down closer to 240 range? seems like an easy fix, if such a transformer would fit. That way we wouldn’t have to install 112.5 kVA transformer for every 13 charging stalls. This, as you can, imagine, is a huge expense and why it is challenging in North America to adopt chargers when we have 4 different three phase AC systems, while Europe just has 1
OMG! Was that an Apple II?!? Love it!
It’s an SE/30 😂
Thanks for the lessons!
Not quite right, in Europe, 32A at 230V (7kW) is available in most places, such as wired-in home EVSEs.
Only if you resort to “emergency” 3 pin plug charging will you be limited to 3 or 4kW.
In public and workplace settings you will always get 3 phase, which means 22kW.
Yes, my Tesla charges at 22kW. At home.
Even 44kW is possible by the standard.
And most new homes get 3 phase nowadays.
All for one more conductor in the connector and cable. A bit short sighted of North America to adopt the NACS/Tesla connector which can only ever support single phase.
That was a fantastic video. Thank you for sharing your knowledge.
Thank you for watching! -Travis
One of our biggest problems was never allowing 3 phase to residential. 208 3 phase would of allowed evse's to be made 208 like they are in europe, and would of allowed the very easy scaling of 480v 3 phase and that would fix all these problems.
Personally i see 240v split phase becoming a problem in the future and the lack of residential 3 phase leading to issues
The lack of residential 3 phase isn't really an issue. While 3 phase charging could have reduced conductor sizes, it's not an enormous difference and the cost of conversion would be huge. The main rationale for split phase power is that the voltage potential is lower so less risk of arcing and higher safety margins.
@EVBuyersGuide as we move into a world of electric utilities like hot water, stoves, heating, and clothes dryers, electrical usage is going up in the average home drastically. The single phase network was never designed to support this volume of high demand utilities. I bought a house with a 50A service in 2023. That's it. That's all it needed to supply everything for the whole house. I had to upgrade it because my ev ate 30A and it did trip the main, but prior to that ev it wasn't needed because nothings electric. A hot water heater is 20A, a stove is 40-50A, a dryer is around 20A, I saw an electric heating system that was 100A for a 2500sqft house! Yes heat pumps would help but not when it's 5 degrees out. 208 3 phase would cut down current by a third, and maybe we wouldn't need 350A mains on homes today for high electrical houses
We have historical analogies we can look back on. When air conditioning first hit the market there were the same concerns and the utilities and the grid just adapted. If everyone replaced their car with an EV in the same year this would be an issue, but the gradual replacement is less likely to be an issue. It is entirely possible to live with an EV and charge slower. For instance I (Alex) live off the grid and my inverters max out at 19 kW continuous so the answer is: charge slower. At 3kW we're still talking a solid 30kWh charge overnight which is 60-120 miles of driving depending on the vehicle, well over the average daily commute.
@@EVBuyersGuide I live in nyc and air conditioners certainly cause problems for the grid during the summer. There are notable brownouts throughout the whole area the hotter it gets. Thankfully most of the cities infrastructure is still built around gas and fuel rather than electric outside of it, or the grid would implode.
EV charging has already been documented to be an issue, and charging restrictions have already been implemented by local municipalities due to how hard they're hitting the grid.
According to the utilities I have spoken with, the electric vehicles are fairly easy to integrate because of several factors. The demand is fairly constant. Regardless of the weather, air-conditioning based blackouts are harder to cover with grid improvements because they occur relatively infrequently compared to the average load.. an electric vehicle on the other hand would cause the daily load to increase steadily overtime, allowing a profitable case for expansion of the grid. In addition to that, offer smart, charging profiles, and generally speaking charging reaches its peak late in the day, after air-conditioning demand has dropped
Excellent. Well done.
I learned something today thanks to you and you earned a subscriber. Awesome job thank you!
Thanks for watching and subscribing! -Travis
Omg the old Mac! I think I love this man.
The reason it’s single please and not two phase is because only one of the three phases from the utility feeders along with the neutral runs to the transformer.
Extremely informative and helpful 👍
I wish 3-phase charging was a thing in the US. Level 2 charging would be so much faster.
i'm surprised no one has mentioned the very common three phase Wye transformers that deliver 120v/208v without the need for a secondary transformer. This works great for EVSE's and does not require compatibility with 277v.
That’s discussed in the video. It’s very rare to have a utility deliver 208 in the USA, power is delivered as 480v and you have to step down yourself
At first i was just wondering why not just wire your three phase transformer with a wild leg, then i realized the load balance with EV chargers all being on that phase would not be optimal to put it nicely
Makes sense now why N.America is the only one with the Tesla handle.
OKAY I edited before posting... 🤣😂
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While we're at it why not use 480 AC for EV charging ? Anything under 600v is basically the same .... Nevermind... I googled it 480v is 600v+ so that's not going to work. Because once you go over 600v you need 1k rating and a tons of testing and the insulation will be bigger than the wire 🤣😂
Nice and concise covering the AC voltage waves. 👍