No indication of this charger (made in Buffalo, incidentally) uses 277 as there is nothing on the nameplate regarding that. It says the input is '480' with an allowable range of 360-528 volts, 50/60 HZ. Good for Europe or the States. Since this is not used in the home there'd be no reason for it, and other reasonably high power rectifiers rarely have the neutral connection, whether 208, 480, or 600 volts.
The old 40 ampere chargers can take a lower voltage (277 nominal maximum) only, and are single-phase only. Whereas this unit is obviously designed expressly for Supercharger service, and single-phase operation at a low or high voltage is unnecessary.
Whether internally this is a 3 phase, or like Porsche, a 6 phase unit; is unspecified, but the neutral isn't necessary in any case as the loading on the phases is balanced.
Forcing a job for a neutral is a bit silly, as its much less parts to just use the 3 phase input as-is and not use multiple single phase powered supplies. The only downside comparing this nameplate with a v1 nameplate is this unit cannot be used on 240 volts as the v1 models could have been. But then so few were that it surely wasn't a design constraint and hence 360 volts is the lowest operating voltage of this unit.
Electricians typically send 4 wires in the conduit, which is incidentally required here as one of the wires is needed for the equipment grounding conductor as plastic pipe is non-conductive. If you see 5 wires, then it is because they do it out of force of habit. I've seen many pieces of equipment where the neutral wire is uncommitted just because somebody thought they'd need it.
Rather like the Nema 14-50R (4 prong) in people's garages. The neutral is rarely used. Tesla gets most of the credit for 'standardizing' the 'Recreational Vehicle' connection - as at least half the other companies are using this as opposed to a 6-50R (3 prong).
So I am pretty positive the V1 and V2 superchargers are based off the same modules as in the S and X cars (two generations of them). And I am pretty sure that means they utilize the 277v power. I really don't think Tesla would spend money on a neutral conductor if it was not needed (given how very cost optimized they are). ;-)
I know the superchargers I have seen in person (not V3) also say they take 480v (but I am unsure if I have ever seen any V1 units, or if everything around here is V2, not actually sure how to tell).
How can the Porsche unit be 6 phase? Is that just two sets of three phase rectifiers for capacity and redundancy? I think the V1/V2 super chargers are 12x 277v modules, so four on each of the three phases (connected to neutral). Urban ones have 6x dedicated to each stall, long range ones can flip back and forth to either car?
I had no idea the original superchargers could be used on 240v btw! Fascenating, but makes sense. I think they realized any power company was going to want something as high draw as a supercharger to be distributed across the phases. ;-)
Eprosenx: Very interesting regarding the 277 volt allowability.
One question: Since all large battery Teslas now have 48 ampere chargers only, are you implying that the 48 ampere charger in the model 3 is substantially different than the 48 ampere charger in the S/X? Why would Tesla have more than one model for the exact same functionality?
Of course, one thing I do not understand is why Tesla is constantly changing its mind. People who have bought an older HPWC are now incompatible with the load sharing arrangement of the new Models, as well as those who RECENTLY bought a 72 ampere charger (again, the customer having no choice as it was the only size available for their battery choice) now have no Tesla HPWC available to charge it at any more than 48 amperes.
The silly thing is, how much you want to bet that a high mileage, 500 mile range , Cybertruck owner who needs to drive hundreds of miles per day occasionally for work, and whose home is not on a supercharge route, will not be able to recharge in time with just a 48 ampere rate, and Tesla will be forced to change its mind again?
Yes, the charger in the Model 3 was a completely new unit (next generation). I think a lot of it has to do with internationalization. In the Model three it is actually three 16a modules. They de-populate one of them for the shorter range cars (only 32a capable). Then having the three modules allows european cars to charge at 16a three phase. Some countries it is 230v phase to neutral for each of the three (400v phase to phase), and other countries it is 230v phase to phase I think in Europe. Then I think at least in the UK one of the modules can flip over to parallel with one of the other phases and the car can charge at 32a single phase I think if you only have a single phase mains connection.
Yeah, I am super frustrated that Tesla has stopped selling the OLD Wall Connector. I have friends that JUST bought new Wall Connectors before the switch. One of them planned to buy three more of them (and we pre-wired four 100a circuits in the house just for this). The one possible saving grace is that I think there is an RS-485 port on the new Wall Connector, so maybe they will release software that lets you pair the new one to the old ones and do some kind of sharing? Still though, 48a limited...
On the Cybertruck thing: I am right there with you. My assumption has been that it would have an 80a onboard charger since with a 500 mile battery and it uses a ton more per mile you are going to need some serious recharge capability if you want to turn around and do it the next day (think actual contractors). I would not be surprised in the slightest if we see another version of the new Wall Connector that has the WiFi and other improvements, but that can go up to a 100a circuit again (but of course they will sell it for $700 instead).
I totally understand though why the new Wall Connector is a good deal for Tesla. it is probably much less to manufacturer than the last gen one since the contactor can be a lower rating and more importantly, the wire is lower gauge and shorter. It is a slick solution for all new currently sold cars. Sucks for former owners... They should have kept selling the old ones for a while...
(also, I bet they have additional revenue opportunities with the new one - with WiFi, what stops Tesla from letting you install one and charge other Tesla owners for use using the same billing setup as Superchargers? - actually come to think of it, I wonder if my Wall Connector has a serial number embedded in it today - could Tesla just flip the switch and enable billing like that via a software update in all the cars?)