What is the fastest model 3 charge rate other than Supercharger

[Big Earl]

That's interesting! I installed the charger at our shop, where we have both 120/208Y and 277/480Y panels. I connected it to a 120/208 panel, two legs on a dual pole 60A breaker are delivering ~ 215VAC single phase power to the wall charger. The manual says it is to be hooked up to 208V - 250V single phase, so I did not think of connecting to to 277V.

Would you mind sending me a link to the thread where you read this? Has anyone had any bad results?

If 277V makes that much of a difference, individuals who only have single phase could install a couple of buck/boost transformers 'in front' of their wall charger and take their single phase 240VAC up to 277VAC. My only concern is damaging the charger, or worse, the batteries.

Thanks!

More info here: Info from Tesla - 277v feed to Wall Connector (HPWC) - Which Cars Support It

Be sure you set your wall connector dip switch to line-to-neutral instead of line-to-line if you're connecting it to 277 volts.

You should be able to get an extra ~2 kW charge rate if you hook it up to your high voltage panel.

 

[cobrahead]

More info here: Info from Tesla - 277v feed to Wall Connector (HPWC) - Which Cars Support It

Be sure you set your wall connector dip switch to line-to-neutral instead of line-to-line if you're connecting it to 277 volts.

You should be able to get an extra ~2 kW charge rate if you hook it up to your high voltage panel.

Thanks for the link! I will read up on it tonight.

 

[cobrahead]

Yep, 277 volts rocks. 13 kW is about the max it'll do before it starts backing the amps down, as shown in this picture.

Wait, will this only work on the LR model? Or does the 277V magically allow any M3 battery model to charge at the higher rate? Thanks again!

 

[Vines]

277v allows higher charge rates for all Model 3 (I think), as the magic is power delivered to the battery is a function of Volts x Amps. So for instance any charger will give less miles per hour on a 208v system vs a 277v system, for the same amps. Some X and S do not like 277vac last I checked and might have issues with that voltage.

LR cars charger are maxed at 48A, but that is 13.3 kW at 277vac and 10 kW at 208vac. I don't see why the MR cars are any different besides a lower maximum charge amps through the HPWC. I just don't have any firsthand knowledge.

 

[Big Earl]

277v allows higher charge rates for all Model 3 (I think), as the magic is power delivered to the battery is a function of Volts x Amps. So for instance any charger will give less miles per hour on a 208v system vs a 277v system, for the same amps. Some X and S do not like 277vac last I checked and might have issues with that voltage.

LR cars charger are maxed at 48A, but that is 13.3 kW at 277vac and 10 kW at 208vac. I don't see why the MR cars are any different besides a lower maximum charge amps through the HPWC. I just don't have any firsthand knowledge.

I agree. I haven't tested a MR or SR, but I suspect they'll also benefit from the higher voltage.

This is particularly beneficial in commercial environments where charging stations are typically hooked up to 208 volts rather than residential's 240 volts.

 

[eprosenx]

I agree. I haven't tested a MR or SR, but I suspect they'll also benefit from the higher voltage.

This is particularly beneficial in commercial environments where charging stations are typically hooked up to 208 volts rather than residential's 240 volts.

Yeah, so now that SR and SR+ and MR Model 3’s are out we need some folks to test them on 277v feeds!

I am curious what causes the limit in the LR at 13kw or so (which causes it to back down the amps by one or two at 277v). Perhaps the MR/SE/SR+ won’t have this limit and so 277v will be even more beneficial to them?

Note that Tesla no longer technically supports new installs of wall connectors at 277v due to an intermittent issue with newer S and X units (that just causes them not to charge in some situations), but there is nothing unsafe about it and the unit was designed and rated for it. So if you are only going to use it on a model 3 then I would totally do 277v if available.

There is even someone in the forums here who uses a UMC Gen 1 and Gen 2 at 277v and it worked! (Though this is *really* not supported since it is unclear if all the internal components are rated for this and having a 14-50 adapter that be provides 277v is a bad idea).

So to answer the original question: Short of a DC fast charging solution like a supercharger or CCS, I would say 277v is the fastest way to charge a model 3. But very marginally faster than 240v.

 

[cobrahead]

277v allows higher charge rates for all Model 3 (I think), as the magic is power delivered to the battery is a function of Volts x Amps. So for instance any charger will give less miles per hour on a 208v system vs a 277v system, for the same amps. Some X and S do not like 277vac last I checked and might have issues with that voltage.

LR cars charger are maxed at 48A, but that is 13.3 kW at 277vac and 10 kW at 208vac. I don't see why the MR cars are any different besides a lower maximum charge amps through the HPWC. I just don't have any firsthand knowledge.

Ok, let me see if I understand this so far. The charge rate of any given model is capped using amperage only, not power or voltage.
Therefor by cranking up the voltage, while keeping the amperage at the same level, the power (wattage) goes up and the car charges faster?

My wall charger is connected to our 208V service, which runs a little 'hot' ~218V, drawing 32A, I won't get into PF (let's assume 100%) so we were charging today at 7kW. If I bump that up to 277 I could get ~8.85kW. If it was being used on a single phase service at 240 it would be 7.7kW. AND if it was turned all the way up to 295V at 32A we could charge at 9.4kW ... I only mention that because of the other thread. In the original thread Eprosenx talked to someone at Tesla who said the wall charger and Model 3 in conjunction could handle as high as 300V.... though I would not want to push it.

I agree. I haven't tested a MR or SR, but I suspect they'll also benefit from the higher voltage.

This is particularly beneficial in commercial environments where charging stations are typically hooked up to 208 volts rather than residential's 240 volts.

Many commercial electric services are simply 120/208Y ... so without adding a step up transformer they are stuck with 208. The other commercial settings who have 277/480Y, 240/480D, or even true high voltage services, all use transformers to get the voltages they need for their large motors and then step down to 120V, be it 120/208Y or 120/240D. Even then, if the electrician installing the charger follows the instructions, it is going to be 208 or 240. It is unfortunate that they have 'de-rated' the wall charger, though it sounds like they had to with some models not being able to charge at 277.

Yeah, so now that SR and SR+ and MR Model 3’s are out we need some folks to test them on 277v feeds!

I am curious what causes the limit in the LR at 13kw or so (which causes it to back down the amps by one or two at 277v). Perhaps the MR/SE/SR+ won’t have this limit and so 277v will be even more beneficial to them?

Note that Tesla no longer technically supports new installs of wall connectors at 277v due to an intermittent issue with newer S and X units (that just causes them not to charge in some situations), but there is nothing unsafe about it and the unit was designed and rated for it. So if you are only going to use it on a model 3 then I would totally do 277v if available.

So to answer the original question: Short of a DC fast charging solution like a supercharger or CCS, I would say 277v is the fastest way to charge a model 3. But very marginally faster than 240v.

Yeah, I will have to give it a try. Really though, anyone who wants to get in the 275V-290V range at home could use a boost transformer and get the same results. Like you said, it is marginally faster and might not be worth the expense.

How does CCS charge faster?

Thanks to everyone for their input!

 

[Big Earl]

Ok, let me see if I understand this so far. The charge rate of any given model is capped using amperage only, not power or voltage.
Therefor by cranking up the voltage, while keeping the amperage at the same level, the power (wattage) goes up and the car charges faster?

My wall charger is connected to our 208V service, which runs a little 'hot' ~218V, drawing 32A, I won't get into PF (let's assume 100%) so we were charging today at 7kW. If I bump that up to 277 I could get ~8.85kW. If it was being used on a single phase service at 240 it would be 7.7kW. AND if it was turned all the way up to 295V at 32A we could charge at 9.4kW ... I only mention that because of the other thread. In the original thread Eprosenx talked to someone at Tesla who said the wall charger and Model 3 in conjunction could handle as high as 300V.... though I would not want to push it.



Many commercial electric services are simply 120/208Y ... so without adding a step up transformer they are stuck with 208. The other commercial settings who have 277/480Y, 240/480D, or even true high voltage services, all use transformers to get the voltages they need for their large motors and then step down to 120V, be it 120/208Y or 120/240D. Even then, if the electrician installing the charger follows the instructions, it is going to be 208 or 240. It is unfortunate that they have 'de-rated' the wall charger, though it sounds like they had to with some models not being able to charge at 277.



Yeah, I will have to give it a try. Really though, anyone who wants to get in the 275V-290V range at home could use a boost transformer and get the same results. Like you said, it is marginally faster and might not be worth the expense.

How does CCS charge faster?

Thanks to everyone for their input!

Yes and no. The charger still has a wattage limit, which is why the Model 3 long range starts backing down from the full 48 amps when it’s charging on 277 volts. I would expect similar behavior in short and mid range variants. You might get 8.5 kW out of the them, but probably not 9. Cranking the voltage up to 280 or 290 volts will not yield faster charging.

CCS, CHAdeMO and Tesla Superchargers are all DC charging and bypasses the car’s onboard AC charger.

 

[cobrahead]

Yes and no. The charger still has a wattage limit, which is why the Model 3 long range starts backing down from the full 48 amps when it’s charging on 277 volts. I would expect similar behavior in short and mid range variants. You might get 8.5 kW out of the them, but probably not 9. Cranking the voltage up to 280 or 290 volts will not yield faster charging.

CCS, CHAdeMO and Tesla Superchargers are all DC charging and bypasses the car’s onboard AC charger.

Cool. I will definitely try 277 and report back, not sure how soon I will be able to get that done... hopefully in the next couple of weeks. Does CCS or CHAdeMO work with the Model 3 yet?

Fingers crossed they get our supercharger back online soon!

 

[eprosenx]

Yes and no. The charger still has a wattage limit, which is why the Model 3 long range starts backing down from the full 48 amps when it’s charging on 277 volts. I would expect similar behavior in short and mid range variants. You might get 8.5 kW out of the them, but probably not 9. Cranking the voltage up to 280 or 290 volts will not yield faster charging.

CCS, CHAdeMO and Tesla Superchargers are all DC charging and bypasses the car’s onboard AC charger.

So I suspect you are right in that the MR and SR variants may also have to bump down the amps at some wattage due to some limit, though it is also possible that the limit is not a factor if say it is a limit of some bus or cable which is the same size in the LR and SR/MR so because the SR/MR is only rated to 32a you are nowhere close to that limit.

That is probably just wishful thinking, but worth testing!

I am guessing btw that the MR/SR only have two of the three charger units populated. (though one wonders how they will deal with this ok European models that accept three phase charging- would it be a jerk move to just draw zero from one of three phases?

 

[Big Earl]

So I suspect you are right in that the MR and SR variants may also have to bump down the amps at some wattage due to some limit, though it is also possible that the limit is not a factor if say it is a limit of some bus or cable which is the same size in the LR and SR/MR so because the SR/MR is only rated to 32a you are nowhere close to that limit.

That is probably just wishful thinking, but worth testing!

I am guessing btw that the MR/SR only have two of the three charger units populated. (though one wonders how they will deal with this ok European models that accept three phase charging- would it be a jerk move to just draw zero from one of three phases?

Only 2 out of 3 charging boards are populated on MR and SR, so I would expect 2/3 of the increase that a LR gets. If 277 volts gives the LR an additional 1.5 kW (just guessing), expect MR and SR to get an extra 1 kW.

 

[IROAR]

Do you have a Gen 1 mobile charger running at 40A continuous, or a Gen 2 mobile charger (included with Model 3) running at 32A continuous? Or something else?

Don't know. Bought my car November 2018

 

[MorrisonHiker]

Don't know. Bought my car November 2018

I think the Model 3 always shipped with the Gen 2 32 Amp Mobile Connector.

Since mid-December 2017, all cars (S, X and 3) have the Gen 2 32 Amp Mobile Connector.

 

[Sophias_dad]

Yeah, I will have to give it a try. Really though, anyone who wants to get in the 275V-290V range at home could use a boost transformer and get the same results. Like you said, it is marginally faster and might not be worth the expense.

How does CCS charge faster?

Thanks to everyone for their input!

I could be wrong, but I think a boost transformer would cost >$1k and you'd end up losing at least a few percent in heat in the windings. Not really worth it to go from 240 to 277V, IMHO...

I looked into getting a 277 to 240V transformer for the 'slow' charger at work, and there was no viable option(pricewise). The 'slow' charger is likely on a 3:2 transformer, delivering a measly ~183V to a j1772 connector. I presume the other direction would be the same(or probably even the same transformer connected in reverse!)... Recall that its gotta be rated to handle ~14kw continuously.

 

[Dr. J]

Don't know. Bought my car November 2018

37 miles of range per hour is unusually high for a Gen 2 UMC operating at 32 amps, per this post: Miles per hour reading during charge

 

[niekbergboer]

Someone here posted about hooking up at their work which has 480v 3 phase, the hooked up a HPWC to 277v and got a higher charge rate at 48 amps.

That is an interesting options that we, in Europe, unfortunately do not have. We typically have either 240V 16A 3-phase, for 11 kW. On the UMC, though, we are limited to single phase, so that is 240A 16A max (for 3.8 kW) best case; often, local regulations put lower limits on either the outlet, or on sustained load vs. short-term load. That means you may be looking at 13A, 10A, or even 8A (3.1 kW, 2.4 kW, and 1.9 kW respectively).

At home, I use the Tesla Wall Charger on 240A 16A 3-phase, and I get 11 kW, and 70 km/h (~43 mph).