Model S - HPWC (High Power Wall Connector)

[Cottonwood]

As a data point my HPWC cable gets warm at 80A but not hot at all. Maybe my voltage is 200V, not 240V.

BTW recently my Tesla only charges at 71A rather than full 80A, and I asked Tesla to check the logs. I thought my circuit's internal resistance or transformer capacity caused some voltage drop, but the engineer told me that my car's one phase of dual chargers is broken hence 71A. They offered me to change the on-board charger unit but I didn't ask because it's a minor issue.

However I thought "a phase is broken" seemed a little bit odd, since my circuit is 200V single phase, not three phase.

My guess is that you have 3-phase chargers where all three sub-chargers are connected in parallel. The 3-phase chargers seem to have about 10% more capacity than the single phase chargers. If I take 80 Amps * 5/6 * 1.1, it is 73 Amps; that is pretty close to your 71 Amps.

If I were you, I would have this problem fixed at the next regular service visit. One problem can sometimes be a warning of another to follow.

 

[FlasherZ]

My guess is that you have 3-phase chargers where all three sub-chargers are connected in parallel. The 3-phase chargers seem to have about 10% more capacity than the single phase chargers. If I take 80 Amps * 5/6 * 1.1, it is 73 Amps; that is pretty close to your 71 Amps.

If I were you, I would have this problem fixed at the next regular service visit. One problem can sometimes be a warning of another to follow.

That's not really how they work - the limitation is amps and you really can't apply the 10% factor in that way. The new chargers actually have 20% more capacity, but it's only effectively 10% because of EU's 230V nominal vs. the US spec of 250V. (230V * 96A = 22 kW; 250V * 80A = 20 kW)

In a single-charger car, there are 3 sub-chargers; in a dual-charger car there are 6 sub-chargers. Each is capable of 16A. So single-charger car has up to 48A, dual-charger is up to 96A when the gen2 chargers are used. The loss of one sub-charger would still leave 80A capacity, while the loss of one entire phase connector would be 2 sub-chargers or 32A, leaving 64A capacity.

The chargers are capable of three-phase, but the cable attached to the car simply joins all three phases together to the single phase line conductor if you have single-phase power.

I suspect you're seeing a compromise in the car software that seeks to ensure that the shared neutral isn't overloaded on the other (remaining good) charger, so it reduces by an additional 8A, leaving 72A. At that point it just becomes a case of that 1A difference we sometimes see (79/80 vs. 80/80), so you get 71A.

 

[hiroshiy]

That's not really how they work - the limitation is amps and you really can't apply the 10% factor in that way. The new chargers actually have 20% more capacity, but it's only effectively 10% because of EU's 230V nominal vs. the US spec of 250V. (230V * 96A = 22 kW; 250V * 80A = 20 kW)

In a single-charger car, there are 3 sub-chargers; in a dual-charger car there are 6 sub-chargers. Each is capable of 16A. So single-charger car has up to 48A, dual-charger is up to 96A when the gen2 chargers are used. The loss of one sub-charger would still leave 80A capacity, while the loss of one entire phase connector would be 2 sub-chargers or 32A, leaving 64A capacity.

The chargers are capable of three-phase, but the cable attached to the car simply joins all three phases together to the single phase line conductor if you have single-phase power.

I suspect you're seeing a compromise in the car software that seeks to ensure that the shared neutral isn't overloaded on the other (remaining good) charger, so it reduces by an additional 8A, leaving 72A. At that point it just becomes a case of that 1A difference we sometimes see (79/80 vs. 80/80), so you get 71A.

@Cottonwood, @FlasherZ,
Thanks for the explanation. Fortunately my car is almost trouble free except at the delivery my car somehow got Euro TPMS unit giving TPMS error all the time. After one month of engineers coming to my ho e and office a few times, they found that a wrong TPMS was in my car.

So I'm not sure when the next service visit would be, but will take your advice and have them fixed soon.

Re; 71A, now I think I understand - so my one sub charger is broken and it is still capable of handling 200V 80A, but for safety it reduces the current.

A little bot off topic but in the latest Tesla blog article in Japan, they said single charger equipped vehicle is compatible with this CHAdeMO charger, but vehicle with dual chargers is not. I thought single charger and dual chargers is just difference of number of chargers, but it seems I was wrong...

 

[FlasherZ]

Re; 71A, now I think I understand - so my one sub charger is broken and it is still capable of handling 200V 80A, but for safety it reduces the current.

Correct. I suspect that on single-phase the car is limiting your good charger to 40A, and your bad charger to 32A, total 72A and you only see 71A because of headroom) to protect the neutral conductor.

 

[Cottonwood]

A little bot off topic but in the latest Tesla blog article in Japan, they said single charger equipped vehicle is compatible with this CHAdeMO charger, but vehicle with dual chargers is not. I thought single charger and dual chargers is just difference of number of chargers, but it seems I was wrong...

I have dual chargers and a CHAdeMO adapter and they all work together. It sounds like that is true for you as well. That blog is probably mistaken.

 

[scaesare]

A little bot off topic but in the latest Tesla blog article in Japan, they said single charger equipped vehicle is compatible with this CHAdeMO charger, but vehicle with dual chargers is not. I thought single charger and dual chargers is just difference of number of chargers, but it seems I was wrong...

Odd... the on-board chargers are for AC charging and are bypassed for DC charging such as CHAdeMO...

 

[meltoots]

I installed a HPWC yesterday at a second home of mine to be able to quickly charge.

Only issue I had was after I had it all set up, dip switches set for 80 amps, my MS would only charge at 40 amps.
I have dual chargers, and a 100 Amp circuit set up. I read on this site to try to "flash" or turn the 100 amp circuit on
my panel on and off. I did that and fixed my problem. I then charged at 80 amps. Woohoo!
So if you are only getting 40 amps instead of 80 amps on your HPWC, try turning circuit breaker on and off.
It worked for me!

Love charging at 56-58 miles per hour. Sweet. As an added bonus I charged up to 259 rated miles, which is the highest
I have ever seen on my P85D

 

[Andyw2100]

Love charging at 56-58 miles per hour. Sweet. As an added bonus I charged up to 259 rated miles, which is the highest
I have ever seen on my P85D

Did you have a reason why you wanted to do a 100% charge? I ask because you didn't mention going on a trip or anything, and I just wanted to make sure you knew that in general the Tesla advice is not to charge to 100% unless you need to.

 

[Klaus]

HWPC dip switch setting changes require the power to the HPWC to be cycled off and on to be registered. Presumably that was missing.

 

[efusco]

Just an observation (hopefully not previously addressed in the prior 91 pages).
I had my HPWC cord replaced at my last service visit because the remote charge door opening feature was not working well, I had to sometimes hold the charger handle over the hatch window to get it to work.
The replacement cord not only works MUCH better for charger door opening, but I also found that it is much more flexible than my prior cord (which was also a replacement maybe 1 year ago because of overheating of the handle/connector. My prior cord could not really be looped over the cord organizer, it was far too stiff to be practical to do so. But this new one forms into nice loops quite easily. I don't know exactly what was changed, maybe just the rubber compound in the cord, but it is a very nice improvement.

 

[FlasherZ]

Just an observation (hopefully not previously addressed in the prior 91 pages).
I had my HPWC cord replaced at my last service visit because the remote charge door opening feature was not working well, I had to sometimes hold the charger handle over the hatch window to get it to work.
The replacement cord not only works MUCH better for charger door opening, but I also found that it is much more flexible than my prior cord (which was also a replacement maybe 1 year ago because of overheating of the handle/connector. My prior cord could not really be looped over the cord organizer, it was far too stiff to be practical to do so. But this new one forms into nice loops quite easily. I don't know exactly what was changed, maybe just the rubber compound in the cord, but it is a very nice improvement.

The stranding of the cable plays an important part, too - finer stranding means more flexibility of the cord. It also presents a greater chance of failure as the occasional strand breaks in the cable, especially at stress points like the handle connection and terminal lugs. This is why the NEC has lower ampacity specifications for flexible cord than sturdier infrastructure wiring. It's certainly a trade-off; the use of 4/0 welding cable (very finely stranded for manual use in welding) is not rated for use in infrastructure wiring for the reason I mentioned, although there are some cable options that come very close - they're built with much thicker insulation for protection against conductor failure.

 

[meltoots]

Did you have a reason why you wanted to do a 100% charge? I ask because you didn't mention going on a trip or anything, and I just wanted to make sure you knew that in general the Tesla advice is not to charge to 100% unless you need to.

Yep, had a long run yesterday. But it was nice to see the extra miles!

 

[Andyw2100]

Yep, had a long run yesterday. But it was nice to see the extra miles!

Excellent. Glad to hear it. Just trying to watch out for another new P85D owner!

 

[Bugeater]

Note that if you cycle the HPWC on and off you will chagellrge a 0 amps. You have to cycle it off and on to get useful results.

 

[Atebit]

I'm thinking about getting a HPWC soon. Any rumors about major changes/updates in the pipeline? I'm not sure what these would be, though.

 

[ChrisPDX]

There's been rumors with the UMC being changed due to the NEC guidelines and the fact Tesla is not making a few adapters for it anymore. But nothing I recall with the HPWC. Since they are pretty committed with their plug design, I would not expect any major changes in the future. They could change the look of it, but when it comes to the critical parts like the plug and charging protocol (J1772 standard), it should remain unchanged for a very long time. I have one on my single charger MS and I'm very happy with it. Much more beefy then the UMC and since I run it at half the rated capacity, it should last for long time.

 

[Cosmacelf]

Other than some difficulty of installation (bending thick gauge supply wire), I haven't heard of any systemic problems with the HPWC. So other than a tweak here and there, I don't forsee any significant changes. Early HPWCs did have a fusing problem, but that was years ago now.

And I agree about the UMC, I suspect (with no concrete proof) that a redesign is in the works there. What's the NEC rule change that might affect the UMC?

 

[FlasherZ]

Other than some difficulty of installation (bending thick gauge supply wire), I haven't heard of any systemic problems with the HPWC. So other than a tweak here and there, I don't forsee any significant changes. Early HPWCs did have a fusing problem, but that was years ago now.

And I agree about the UMC, I suspect (with no concrete proof) that a redesign is in the works there. What's the NEC rule change that might affect the UMC?

NEC 2014 requires that cord-and-plug connected EVSE's >125V and/or >15/20A to be "fastened in place". I posted the details here:
lack of charging adaptors? - Page 2

Technically, if you believe that the UMC must follow article 625, then as NEC 2014 is adopted, it can no longer hang from the face of the outlet.

 

[jerry33]

NEC 2014 requires that cord-and-plug connected EVSE's >125V and/or >15/20A to be "fastened in place". I posted the details here:
lack of charging adaptors? - Page 2

Technically, if you believe that the UMC must follow article 625, then as NEC 2014 is adopted, it can no longer hang from the face of the outlet.

I'd hope that having one of the roach motel holders would qualify as not "hanging" from the outlet.

 

[SW2Fiddler]

Upgraded from NEMA 14-50 to HPWC today.
Outdoor installation. Set up with #3 to a 70A breaker in a 100A subpanel. #3 from the main (~30 feet) in 1" EMT.
Pearlie May is happy drinking 14kW (she has two "straws" ...chargers) and the voltage stays up at 242/243 even when the house HVAC comes on.
Inspection Wednesday (two days from today).
Question though. re: Weatherproofing. Does the HPWC have a drip channel, inside, at the left-side conduit ingress? Do I spy a weep hole at bottom front? Or should I ask this electrician for some gasket for the outside (see pics)? Same question re: sub panel. This is not in a dry area.