New Model X charging limit to 32A

[ajdelange]

How did you measure the power and the VA?

I track power usage in my house with an eGauge. This is a little box to which one connects the both sides of the line and neutral for voltage measurement and CTs (current transformers) to measure up to 16 (depending on model) currents in whatever wires you can conveniently clip a CT onto, The voltage and current waveforms are sampled at a high enough rates that the integrals I mentioned in my last post can be calculated. The box basically determines VA and power for any set of CTs desired as programmed by the installer who can also set it up to compute harmonic distortion, power factor, vars etc. Naturally, it is on the internet so I can, should the occasion arise, determine the power factor of a selected load from Port Louis. It also keeps 10 years of history. In this case for the latter set of measurements I took an installed CT from one of the air conditioner compressor units and moved it over to the breaker going to the WC.

I assume you can get the power from the car.

You can but the readout is to the nearest kW and the nearest ampere and volt.

Did you measure the volts and amps directly with a meter?

With the eGauge as described above.

When I put in a HPWC I plan to provide some loops in strategic locations so I can measure the current.

You might want to consider the eGauge: eGauge | eGauge Core. You would put CTs on the service, a generator if you have one, the output of your solar system inverter if you have a solar system, and any individual loads you want to monitor (in this case the WC). From anywhere where you can connect to the internet you can see what's going on in your house's electrical system. Program it with your cost per kWhr and it will show you your electric bill. Download the data to prepare load histograms and use that data to size a generator, solar arrays or determine if your service is adequate. etc.

I seem to recall there is a way to communicate with the HPWC to get info from it, but I don't recall what that is.

Sure - tap the CAN bus. It seems pretty obvious that the little pins in the charger plugs are for connecting the WC to the CAN bus to allow the WC to tell the charger how the dip and rotary switches are configured and to allow the OBC to command the contactor in the WC. Of course you will need to be able to figure out what the messages mean and evidently the OBC exchages thousands of these with the car.

Does it have a wifi link???

No, but it obviously has some sort of rf link to be able to open the charge port door.

Please clarify for me.

I gave a pretty complete but at the same time concise explanation of these concepts in my last post. I did it in terms of the integrals involved in order to encompass non sinusoidal voltage and current waveforms but you can avoid those if you know the Fourier series expansions of the waveforms by working with each harmonic separately and just multiplying the rms values for each harmonic then adding the results as cross frequency terms all integrate to 0. Or you could just ignore the harmonic content. These supplies are clearly switching supplies but I am guessing the switching speed is high enough that the current waveform might be pretty much a sinusoid, That's why I want to look at the current waveform. Try the Wikepedia article on A.C. Power to get you started.

Ok, so what is OBC???

On Board Charger.

It would surprise me greatly if the numbers you recorded turn out to be both accurate and typical.

Keep in mind that the surprising numbers I reported in the first post were based on an improperly configured CT and are definitely not pertinent to this discussion. The numbers measured with a properly configured CT ( 0.92 - 1) are perfectly reasonable.[/QUOTE]

Do you know what the regulations are for a residence? I know businesses have restrictions and get whacked with penalties if their power factor is too far out of line.

AFAIK residential loads are generally considered to be too small and are generally largely resistive to the point that utilitlies don't care or monitor this. For example, at my summer place (the one with the 600A service I mentioned in another thread) the average load is about 6 kW and the pf averages about 0.95 (though it will occasionally dip below 0.9 for a minute or two). This implies an average reactive load of 1.9 kVAR which isn't enough for Hydro to worry about. They bill by the kWhr, not the kVAhr. Now if you are running an ore crushing operation it is a different matter entirely and the utility is very interested in the VAR load and bill accordingly to the point that such operations invest in capacitor banks, big synchronous motors etc. in order to pull pf back towards 1.

 

[gnuarm]

I track power usage in my house with an eGauge. This is a little box to which one connects the both sides of the line and neutral for voltage measurement and CTs (current transformers) to measure up to 16 (depending on model) currents in whatever wires you can conveniently clip a CT onto, The voltage and current waveforms are sampled at a high enough rates that the integrals I mentioned in my last post can be calculated. The box basically determines VA and power for any set of CTs desired as programmed by the installer who can also set it up to compute harmonic distortion, power factor, vars etc. Naturally, it is on the internet so I can, should the occasion arise, determine the power factor of a selected load from Port Louis. It also keeps 10 years of history. In this case for the latter set of measurements I took an installed CT from one of the air conditioner compressor units and moved it over to the breaker going to the WC.

You can but the readout is to the nearest kW and the nearest ampere and volt.

With the eGauge as described above.

You might want to consider the eGauge: eGauge | eGauge Core. You would put CTs on the service, a generator if you have one, the output of your solar system inverter if you have a solar system, and any individual loads you want to monitor (in this case the WC). From anywhere where you can connect to the internet you can see what's going on in your house's electrical system. Program it with your cost per kWhr and it will show you your electric bill. Download the data to prepare load histograms and use that data to size a generator, solar arrays or determine if your service is adequate. etc.

Thanks. $500 plus transformers is a bit rich, but I will give it consideration.

Sure - tap the CAN bus. It seems pretty obvious that the little pins in the charger plugs are for connecting the WC to the CAN bus to allow the WC to tell the charger how the dip and rotary switches are configured and to allow the OBC to command the contactor in the WC. Of course you will need to be able to figure out what the messages mean and evidently the OBC exchages thousands of these with the car.

I'm not looking to tap anything. That's warranty voiding stuff. I'm talking about an intentional interface in the HPWC. Maybe it doesn't have one and I am confusing it with one of the J1772 chargers I've looked at. I think I would prefer a J1772 charger for the extra utility. An adapter comes with the car and is easy to remove and carry in the car.... if it had a decent console. OpenEVSE has an interface of some sort, wifi I believe.

No, but it obviously has some sort of rf link to be able to open the charge port door.

Not of much use other than opening the charge port door.

I gave a pretty complete but at the same time concise explanation of these concepts in my last post. I did it in terms of the integrals involved in order to encompass non sinusoidal voltage and current waveforms but you can avoid those if you know the Fourier series expansions of the waveforms by working with each harmonic separately and just multiplying the rms values for each harmonic then adding the results as cross frequency terms all integrate to 0. Or you could just ignore the harmonic content. These supplies are clearly switching supplies but I am guessing the switching speed is high enough that the current waveform might be pretty much a sinusoid, That's why I want to look at the current waveform. Try the Wikepedia article on A.C. Power to get you started.

Yes, you other post was more complicated than it needed to be just like this one. There is no point in mentioning the Fourier series. That is overkill in discussing this issue. All you need is to understand is that the real power is the integral of the instantaneous product of the current and voltage. If you wish to do calculations then other methods are needed, but conceptually this says it all without more complicated explanations, or non-explanations.

I do understand the concepts and I stand by my statements. That's why I was asking you to explain what you thought was not correct about what I had posted.

Keep in mind that the surprising numbers I reported in the first post were based on an improperly configured CT and are definitely not pertinent to this discussion. The numbers measured with a properly configured CT ( 0.92 - 1) are perfectly reasonable.

Yeah, so I'm left wondering what info you posted was correct and what wasn't.

AFAIK residential loads are generally considered to be too small and are generally largely resistive to the point that utilitlies don't care or monitor this. For example, at my summer place (the one with the 600A service I mentioned in another thread) the average load is about 6 kW and the pf averages about 0.95 (though it will occasionally dip below 0.9 for a minute or two). This implies an average reactive load of 1.9 kVAR which isn't enough for Hydro to worry about. They bill by the kWhr, not the kVAhr. Now if you are running an ore crushing operation it is a different matter entirely and the utility is very interested in the VAR load and bill accordingly to the point that such operations invest in capacitor banks, big synchronous motors etc. in order to pull pf back towards 1.

If it is one residence that has a more distorted current waveform yielding a much lower power factor which you had mentioned previously even that would not be an issue. But with EVs on the verge of taking off and potentially becoming the norm rather than the exception, even a PF of 0.9 will involve considerable loss of energy and money to the utility if they normally see a residential PF of 0.95.

 

[ajdelange]

It's always wise to think before typing. Take my street as an example: there are about 25 houses. Assume they each draw, on average, the same as mine: 6 kW. The total load for my street's feeder would then be 160 kW. The feeder is 14.4 kV so the current is 10.4 A - call it 10 to simplify. Assuming 2% droop that would be about 4.8 volts or, reflected through the transformers, 288 volts between the substation and my pole. The resistance between the substation and my pole must thus be 28.8 Ω. At pf = 1 the losses would be 2880 W (1.8% of the load). At pf = 0.95 the current in the line goes up to 10.5 amps and there are additional losses of 0.25*28.8 = 7.2 W. At pf = 0.9 the current becomes 11.11 Amps and there are additional I^2R losses of 35.5 Watts. At pf = 0.8 the current is 12.5 amp and the additional losses are 180 W. Do you really think Quebec Hydro would be concerned about any of those? This is why we usually don't pay much attention to pf until it dips down below 0.8.

Now the other thing you are not grasping is that waveform distortion in and of itself does not cause a reduction in power factor. It is the phase relationships between the voltage and current at the fundamental and each of the harmonics (and that's why you need the Fourier analysis when you look at distorted waveforms). But with the Tesla OBC the current waveform is not distorted. It's total harmonic distortion is only about 2.6%.

Summary: The X OBC draws nearly sinusoidal current in phase with the supply voltage. The power factor is nearly unity and the THD is low.

I don't know if anyone really cares about this (except me).

 

[gnuarm]

It's always wise to think before typing. Take my street as an example: there are about 25 houses. Assume they each draw, on average, the same as mine: 6 kW. The total load for my street's feeder would then be 160 kW. The feeder is 14.4 kV so the current is 10.4 A - call it 10 to simplify. Assuming 2% droop that would be about 4.8 volts or, reflected through the transformers, 288 volts between the substation and my pole. The resistance between the substation and my pole must thus be 28.8 Ω. At pf = 1 the losses would be 2880 W (1.8% of the load). At pf = 0.95 the current in the line goes up to 10.5 amps and there are additional losses of 0.25*28.8 = 7.2 W. At pf = 0.9 the current becomes 11.11 Amps and there are additional I^2R losses of 35.5 Watts. At pf = 0.8 the current is 12.5 amp and the additional losses are 180 W. Do you really think Quebec Hydro would be concerned about any of those? This is why we usually don't pay much attention to pf until it dips down below 0.8.

You went through a lot of math there that was of no value. The issue is not that the additional losses are small, the issue is that the aggregate amount is large. Car charging is a new thing. The power company is going to have a shot at new fees on utility bills because one way or the other, car charging is going to result in changes to our utility distribution and more importantly the billing. Don't believe for a minute that any issues of power factor will be ignored.

Now the other thing you are not grasping is that waveform distortion in and of itself does not cause a reduction in power factor. It is the phase relationships between the voltage and current at the fundamental and each of the harmonics (and that's why you need the Fourier analysis when you look at distorted waveforms). But with the Tesla OBC the current waveform is not distorted. It's total harmonic distortion is only about 2.6%.

Summary: The X OBC draws nearly sinusoidal current in phase with the supply voltage. The power factor is nearly unity and the THD is low.

I don't know if anyone really cares about this (except me).

I'm not sure what your point is. The charger won't alter the voltage waveform in any appreciable manner. The trick is to keep the current as close to the same waveform shape as the voltage as practical. You seem to think I don't understand this when I do. You seem to read a lot into my posts that isn't there. The concepts are very simple really. Turning them into equations and numbers may be complicated, but measurements are not so complicated. You also seem to distort numbers I provide. I talked about the utility not being happy with a PF of 0.9 and you did your calculations at 0.95 PF. Doesn't matter really. The utilities are most likely going to get dramatic about this in order to manipulate the regulators. The numbers won't matter because the utility companies won't be engaging in a two sided conversation. It will be all one-sided. Expect your electric bill to be revamped (and raised) in 5 or so years when the utilities declare it to be a crisis.

 

[ajdelange]

You went through a lot of math there that was of no value.

To you perhaps because you either didn't read it or don't understand it.

The issue is not that the additional losses are small, the issue is that the aggregate amount is large. Car charging is a new thing.

The average US male drives 16550 mi/yr. At the rate my X burns power that would require 5792 kWhr. Recognizing that the OBC isn't 100% efficient let's call that 6000 kWhr. In the previous 365 days I used 66,000 kWhr. Thus, if I drive the average and do all my charging at home my electric demand will go up 9.1% and if everyone did the same as I did the utilities (or someone) would have to provide 9% more power. That would, of course, be a challenge for them. I'm not sure if this is what you are about here or if it is power factor. Again I encourage some thought. At the present time about 1% of vehicles on the road are EV's. Thus the increased demand on the nation's electric suppliers would be, based on my usage which is doubtless high even if it pales in comparison to Al Gore's, about 0.1%. It is going to be a while before the emergence of EVs has an appreciable impact on the grid. But someday.... As for power factor the "valuess" math shows that for a reasonable and typical distribution system a power factor as low as 0.8 would impose an additional 0.1% burden on the distribution system (to supply the reactive related I^2R losses) relative to pf = 1.0. Thus at 0.8 pf the system would have to provide not 9% more vars but 9.01%.

The power company is going to have a shot at new fees on utility bills because one way or the other, car charging is going to result in changes to our utility distribution and more importantly the billing.

The utilities will have whatever opportunities to bill the local rate boards grant them.

Don't believe for a minute that any issues of power factor will be ignored.

I'm sure they will be because apparently there aren't any. And even if the chargers did lower the power factor of the house's load to below 0.8 the utilities wouldn't care because the losses, as I calculated in the last post, would be insignificant even if every house had a charger on all the time. This is what the math would tell you if you were to look at it to the point that you understood it. The power factor of the charger (or to be robust we should say the power factor of the single one I have examined at relatively light load) is better than the overall power factor for the combined load of the rest of the house (0.95). Thus no power factor concerns on anyone's part.

I'm not sure what your point is. The charger won't alter the voltage waveform in any appreciable manner. The trick is to keep the current as close to the same waveform shape as the voltage as practical.

I guess the point here is that you seem to be under the impression that waveform shape influences power factor to the point that it is necessary to try to keep the current draw waveform as close to the voltage waveform shape as possible. What determines power factor is not the shape of the current waveform but the phasing of the current pulse WRT the source voltage. Thus the challenge is not to control the shape of the current pulse but the timing. As long as the current and voltage are of the same sign at all times throughout the cycle actual shape doesn't matter (WRT pf).
The early switching power supplies drew a big narrow current pulse which wasn't at all like a sine wave but it occurred when the voltage peaked. Thus the power factor was not reduced though there were plenty of implications with respect to the high harmonic content.

You seem to think I don't understand this when I do.

I can only judge by what you post here.

You seem to read a lot into my posts that isn't there. The concepts are very simple really.

Evidently they are more complicated that you seem to appreciate.

Turning them into equations and numbers may be complicated, but measurements are not so complicated.

That's why I have based my comments on measurements.

You also seem to distort numbers I provide. I talked about the utility not being happy with a PF of 0.9 and you did your calculations at 0.95 PF.

This is how I can tell you aren't actually reading the posts. I gave numbers for power factors of 1, 0.95, 0.9 and 0.8

Doesn't matter really.

Some might question my sanity in taking the time to work the examples you are not reading. I may well be insane but I do derive benefit from all this. I get to take measurements on my new toy and think about things I haven'y been concerned with since I designed power transformers at a summer job many, many years ago.

The utilities are most likely going to get dramatic about this in order to manipulate the regulators. The numbers won't matter because the utility companies won't be engaging in a two sided conversation. It will be all one-sided. Expect your electric bill to be revamped (and raised) in 5 or so years when the utilities declare it to be a crisis.

Logic would seem to dictate otherwise. In the first place, the utilities aren't going to be noticing the increasing load from EVs to the point where it makes a difference for quite a few years. In the second place, a load increase of as much as 9% could probably be handled without the need for additional infrastructure by encouraging charging away from peak times. In the third place the home EV charging load looks better to the utility than the other loads in the modern home. In the fourth place, they aren't having any conversation with you - it is with the state utility boards.

I'm not expecting anything from the utilities directly. What I am expecting is some kind of tax, which could be levied through the utilities, to compensate for the fact that I am using the roads now without contributing any revenue for their maintenance through gasoline taxes.

 

[gnuarm]

To you perhaps because you either didn't read it or don't understand it.

The average US male drives 16550 mi/yr. At the rate my X burns power that would require 5792 kWhr. Recognizing that the OBC isn't 100% efficient let's call that 6000 kWhr. In the previous 365 days I used 66,000 kWhr. Thus, if I drive the average and do all my charging at home my electric demand will go up 9.1% and if everyone did the same as I did the utilities (or someone) would have to provide 9% more power. That would, of course, be a challenge for them. I'm not sure if this is what you are about here or if it is power factor. Again I encourage some thought. At the present time about 1% of vehicles on the road are EV's. Thus the increased demand on the nation's electric suppliers would be, based on my usage which is doubtless high even if it pales in comparison to Al Gore's, about 0.1%. It is going to be a while before the emergence of EVs has an appreciable impact on the grid. But someday.... As for power factor the "valuess" math shows that for a reasonable and typical distribution system a power factor as low as 0.8 would impose an additional 0.1% burden on the distribution system (to supply the reactive related I^2R losses) relative to pf = 1.0. Thus at 0.8 pf the system would have to provide not 9% more vars but 9.01%.

The utilities will have whatever opportunities to bill the local rate boards grant them.

I'm sure they will be because apparently there aren't any. And even if the chargers did lower the power factor of the house's load to below 0.8 the utilities wouldn't care because the losses, as I calculated in the last post, would be insignificant even if every house had a charger on all the time. This is what the math would tell you if you were to look at it to the point that you understood it. The power factor of the charger (or to be robust we should say the power factor of the single one I have examined at relatively light load) is better than the overall power factor for the combined load of the rest of the house (0.95). Thus no power factor concerns on anyone's part.

I guess the point here is that you seem to be under the impression that waveform shape influences power factor to the point that it is necessary to try to keep the current draw waveform as close to the voltage waveform shape as possible. What determines power factor is not the shape of the current waveform but the phasing of the current pulse WRT the source voltage. Thus the challenge is not to control the shape of the current pulse but the timing. As long as the current and voltage are of the same sign at all times throughout the cycle actual shape doesn't matter (WRT pf).
The early switching power supplies drew a big narrow current pulse which wasn't at all like a sine wave but it occurred when the voltage peaked. Thus the power factor was not reduced though there were plenty of implications with respect to the high harmonic content.

If the phase is out, the shape is out. As I previously indicated, real power is measured by integrating/summing the products of the instantaneous measurements of voltage and current. To to measure the apparent power the instantaneous measurements are squared, and summed then the square root is taken (don't worry that I didn't mention the division for the mean, that is just a scale factor to be considered anywhere you wish). Then these RMS values are multiplied to get the apparent power. No need to consider the shape or harmonics or anything else. Just the instantaneous measurements and the time period for the sum.

I can only judge by what you post here.

Evidently they are more complicated that you seem to appreciate.

That's why I have based my comments on measurements.

Did you actually measure the PF of the car charger? I missed that.

This is how I can tell you aren't actually reading the posts. I gave numbers for power factors of 1, 0.95, 0.9 and 0.8

Some might question my sanity in taking the time to work the examples you are not reading. I may well be insane but I do derive benefit from all this. I get to take measurements on my new toy and think about things I haven'y been concerned with since I designed power transformers at a summer job many, many years ago.

You said I'm not reading them, I didn't. In your earlier post you talked about the math a bit, then punt to conclusions. You did calculate the wasted power based on non unity power factor and I missed that you repeated the results for the other two factors. My point about that was the calculation didn't matter. The power companies will use every issue they can raise to alter the rates.

Oh, btw, I read them enough to see the results are entirely based on an assumption that you haven't verified.

Logic would seem to dictate otherwise. In the first place, the utilities aren't going to be noticing the increasing load from EVs to the point where it makes a difference for quite a few years. In the second place, a load increase of as much as 9% could probably be handled without the need for additional infrastructure by encouraging charging away from peak times. In the third place the home EV charging load looks better to the utility than the other loads in the modern home. In the fourth place, they aren't having any conversation with you - it is with the state utility boards.

Exactly. That's why we need to insert ourselves in the conversation. It doesn't matter that they won't feel it for a few years. That is exactly my point. By then it will be a "crisis" and the utilities can get their agenda approved easily to prevent "blackouts", etc. You don't seem to get it, but I hope others will. This is an opportunity to contact out state legislators and let them know that they need to be pro-active about this issue before the utilities declare a crisis. The utilities are already talking about it, but they need to do more than talk. They need to approach the problem from a national perspective rather than a local one.

To prevent costly expansions of the infrastructure we need to steer the utilities to a nationwide, uniform method of controlling EV home charging. Then the utility benefits by having more evenly distributed loading over the course of the day and everyone benefits by using off peak power generation and transmission to lower the costs. Overnight charging can be coordinated at home by the consumer indicating their needs and the charging is adjusted to provide that overnight without undue loading and potentially a lower kWh rate from the utility. I'm getting that now by charging at off peak rates with time of use billing, but I have to manage the times.

I'm not expecting anything from the utilities directly. What I am expecting is some kind of tax, which could be levied through the utilities, to compensate for the fact that I am using the roads now without contributing any revenue for their maintenance through gasoline taxes.

No reason to involve the utilities in your road tax. That is typically added to your vehicle registration fees. I had to pay some hundreds in South Carolina and I know Virginia has that as well. Maryland gives you a rebate when you buy the car. Talk about mixed messages. lol

 

[ajdelange]

I've told you what power factor is, how to measure/compute it and what the power factor measurements are for the Tesla and my houses.
I've told you what the measured loads are on my houses and shown that even if everyone else on my street consumed as much power as I do and had a power factor as bad as 0.8 the utility wouldn't care as that would mean an increase of 0.1% in their required capacity and resistive losses. I've told you that the OBC's current waveform has THD of a couple of percent.

Given that you don't read the posts and don't understand some of the concepts I don't see much point in going round again. If you want to understand this stuff read the posts and/or a basic electrical engineering text.

 

[xyeahtony]

well this got off topic quickly lol

 

[ajdelange]

Let me try to be useful by summarizing a few things that came out here. First a bit of background:
EV charging loads are treated by the NEC (National Electrical Code) as continuous loads. Therefore, the circuit breakers that supply these loads must be rated for 125% of the actual load or the load must be limited to 80% of the breaker size. The breaker is there to protect the wire. You must install a breaker smaller than the wire's rated ampacity.

The NEMA 14-50R is a popular receptacle for clothes dryers, electric ranges etc. It will handle 50 A and can be installed with wiring capable of handling 50 A if protected with a 50A or smaller breaker. In such an installation the maximum allowable load would be 40A and that's what the old Tesla mobile module would tell the car to take (the charging plug tells the car what kind of a supply it is connected to and the car draws current accordingly.

The NEMA 14-50R is apparently often installed on 40 A circuits i.e. with a 40A breaker and wire suitable for 40A. If the old style charger was plugged into such an outlet it would try to draw 40A and the breaker would eventually trip. Therefore, in the second generation of the 14-50P adapter the current demand has been limited to 32 A which is the allowable level for a continuous load behind a 40 Amp breaker.

The wall charger can be wired to a 100A breaker with wire rated for 100 A (or more). Per the code the maximum allowable load for the WC is 80 A.

The model X has an on board charger with up to three modules each capable of 24 A. Prior to some time in late November or early December cars shipped all three modules installed. After that date only two modules are installed or if three are installed only 2 of the 3 are enabled. Thus earlier cars are able to charge at 72A and later ones at only 48A. Telsa now instructs owners to install a 60A breaker which limits allowable draw to 48A. If you have one of the earlier cars you can install a 90A breaker and charge at 72A. Be sure that the right size breaker and wire are used and that the little rotary dial in the WC is set to 80% of the breaker label.

You can share the circuit (with up to a 100A breaker) between more than one car. The chargers inform the cars that they are connected to a shared circuit and from this are able to figure out how much current to ask for.

The on board chargers look like resistive loads. No reactive current is drawn or supplied. The current wave form is a quite pure sinusoid with THD of around 2.5%

 

[TexasEV]

The NEMA 14-50R is a popular receptacle for clothes dryers, electric ranges etc.

Not clothes dryers. Virtually all clothes dryer outlets are 14-30 (or 10-30 in older homes).

 

[tga]

The model X has an on board charger with up to three modules each capable of 24 A. Prior to some time in late November or early December cars shipped all three modules installed. After that date only two modules are installed or if three are installed only 2 of the 3 are enabled.

This isn't entirely correct. Only very early X's came with 72A chargers or 72A chargers software limited to 48A. Those cars could be upgraded to 72A charging capacity over-the-air.

Later cars came with either 48A or 72A hardware, depending on battery size or options ordered. To upgrade one of these cars from 48A to 72A required a service center visit to replace the charger.

In late Nov '18, Tesla stopped installing 72A chargers across the board. All cars built after that date have 48A chargers.

 

[ajdelange]

I have an X that was built in December 1918. It has a 72 Amp charger.

 

[ajdelange]

I wondered why this would be considered funny and then I read it. I'm evidently still stuck in the last century! In fact the car was built in December 2018,

 

[tga]

I have an X that was built in December 1918. It has a 72 Amp charger.

The cut-over date isn't clear. Some have said late Nov, some early Dec. My parents' Nov '18 S 100D has the 72A charger. Tesla was still offering a hidden "off-menu" upgrade to 72A when ordering, but that appears to be gone.

There's been lots of discussion on TMC about this, but suffice it to say, all new S and X built today are 48A only.

 

[ajdelange]

It's been discussed in this thread (around No. 60). Why is it being re-hashed?

 

[DCGOO]

I'm not expecting anything from the utilities directly. What I am expecting is some kind of tax, which could be levied through the utilities, to compensate for the fact that I am using the roads now without contributing any revenue for their maintenance through gasoline taxes.

Indiana charges EV owners an extra $150 annually with License renewal. Called the “EV/Hybid Tax”. Even Prius owners have to pay $50, even though they are 100% gas burners. I think it would be difficult for a utility to collect though. How would they know what I plug in?

 

[ajdelange]

As it turns out 17 states, including VA where I live do this. I can apparently look forward to $64 added on to my registration fee next year. Of course I save $14/yr on emission inspection.

 

[Krazaak]

Originally, the Model X was offered with a 48A charger and a hidden 72A charger option was available for the 90D or P90D. After a while it became an optional $1000 (I believe) upgrade from 48A to 72A available on any X order. Then it was changed so that the 75D was a 48A charger and the 100D a 72A charger. Then, in the streamlining change, all Xs are 48A.

I have a 2016 X P100D that was ordered without the optional 72A charger. The SC has quoted me $1,900 to install the upgraded 72A charger, but I've not done it because 48A is more than sufficient for me at home. The only time I might need a 72A charge is a destination charger, especially since many of them are commercial installs at 208V instead of residential 240V Even then, not all destination chargers are 72A, the UI differentiates them as "up to 8kW" or "up to 16kW". Oddly enough, those 2 ratings are just a holdover from the original Model S chargers which were either 40A (single) or 80A (dual). Even with a 48A charger, you can only max out at a 16kW destination charger and even that stands the chance of being slower than at home if it's on a 208V circuit.

I have a gen 2 HPWC and it supports up to a 100A breaker which will support an older dual charger Model S at 80A. Only a 90A breaker is required to provide 72A in the newer (but not newest) Model S/X. 60A will support the max rate on all the currently produced vehicles (MR Model 3 maxing out at 32A).

Personally, I see the corded HPWC as a bit of a waste, unless you already have the NEMA 14-50 installed. Then it's essentially just a nicer looking, more permanently attached gen 1 UMC. If you need to involve an electrician, then just hard wiring it at 60A is the better path.

 

[Krazaak]

Indiana charges EV owners an extra $150 annually with License renewal. Called the “EV/Hybid Tax”. Even Prius owners have to pay $50, even though they are 100% gas burners. I think it would be difficult for a utility to collect though. How would they know what I plug in?

NC charges $130 annually for PEVs, SC is $120/2 years and GA is $200 annually. Even the GA fee isn't that bad compared to the gas tax for a vehicle comparable to the Model X. Even comparing the Model 3 to the gas tax you'd pay on a BMW 340i isn't that bad, but you're paying quite a bit more than if you were driving a 40mpg vehicle.

 

[jboy210]

The NEMA 14-50R is apparently often installed on 40 A circuits i.e. with a 40A breaker and wire suitable for 40A. If the old style charger was plugged into such an outlet it would try to draw 40A and the breaker would eventually trip. Therefore, in the second generation of the 14-50P adapter the current demand has been limited to 32 A which is the allowable level for a continuous load behind a 40 Amp breaker.

Is that a state/local thing? I had a lot of wiring done for the Model X. We installed a signature HPWC, but wanted the option to remove it and use the same wiring for a NEMA 14-50 outlet if we got a different brand EV in the future. So they redid the breakers to be 50 Amps instead of the 40s that were already there. When I asked my electrician about that he said he could not legally connect a NEMA 14-50 outlet to a 40 Amp breaker. It had to be 240v at 50 Amps.

FWIW, we are in California in the SF Bay Area. (13 miles from Tesla )