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Model S - HPWC (High Power Wall Connector)

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Hey, everyone. I recently bought a 2015 P85D with the dual charger upgrade. Naturally, due to my stubbornness, I'd really like to find a Gen 2 HPWC to take advantage of the upgraded chargers. I've seen differing opinions about the benefits of higher vs lower amperage charging, but my question is this: does anyone know how load is distributed across the two chargers? For example, if I charge at 40 amps, will one charger take all 40 amps, or will it split the load 20/20?

Also, with all of the newer gen HPWCs maxing out at 48 amps, as the gen 1/2 HPWC start to fade away, does that make the charger upgrade pretty much useless?
 
Hey, everyone. I recently bought a 2015 P85D with the dual charger upgrade. Naturally, due to my stubbornness, I'd really like to find a Gen 2 HPWC to take advantage of the upgraded chargers. I've seen differing opinions about the benefits of higher vs lower amperage charging, but my question is this: does anyone know how load is distributed across the two chargers? For example, if I charge at 40 amps, will one charger take all 40 amps, or will it split the load 20/20?

Also, with all of the newer gen HPWCs maxing out at 48 amps, as the gen 1/2 HPWC start to fade away, does that make the charger upgrade pretty much useless?

Yes, the dual chargers split the load (above 40 amps IIRC). So if you set it to 42 amps, they would both be used at 21/21. I could be wrong at which setting the load is split but if you look through some old threads, you could probably find the details.

I just found this post which confirms what I stated above: Is the dual charger option useful and worth getting?
On my 80A dual charger S, using <= 40A only the first charger activates. Using > 40A, it splits between the two chargers.

There are plenty of brand new gen 2 HWPC on eBay that would allow you to charge at up to 80 amps with dual chargers.
 
Hey, everyone. I recently bought a 2015 P85D with the dual charger upgrade. Naturally, due to my stubbornness, I'd really like to find a Gen 2 HPWC to take advantage of the upgraded chargers. I've seen differing opinions about the benefits of higher vs lower amperage charging, but my question is this: does anyone know how load is distributed across the two chargers? For example, if I charge at 40 amps, will one charger take all 40 amps, or will it split the load 20/20?

Also, with all of the newer gen HPWCs maxing out at 48 amps, as the gen 1/2 HPWC start to fade away, does that make the charger upgrade pretty much useless?

We have a dual charger model S with a hundred amp breakers to our hpwc. It is great to see 19.2 kilowatt hour going into that battery! Note that it will slow down towards the end to a crawl. Literally runs at 8 amps for a long long time. But then, I have 217000 miles on my car. So yours may do better.
 
Yes, the dual chargers split the load (above 40 amps IIRC). So if you set it to 42 amps, they would both be used at 21/21. I could be wrong at which setting the load is split but if you look through some old threads, you could probably find the details.

I just found this post which confirms what I stated above: Is the dual charger option useful and worth getting?


There are plenty of brand new gen 2 HWPC on eBay that would allow you to charge at up to 80 amps with dual chargers. We have a brand new signature one. If you are interested, feel free to send a PM (Start a Conversation).

This is exactly what I was looking for! Thank you so much! Now I just need to figure out how to come to a decision on which charging philosophy I should go with for standard daily charging; charge for a shorter time at a higher amperage, or longer time at lower amperage.
 
This is exactly what I was looking for! Thank you so much! Now I just need to figure out how to come to a decision on which charging philosophy I should go with for standard daily charging; charge for a shorter time at a higher amperage, or longer time at lower amperage.
We typically aren't in a rush and only charge our cars at 40 amps or so. If we're in a rush, we might bump it up to 48 amps. We have ours (3 load-balanced) on an 80 amp circuit but none of our cars have the 72 (or 80) amp chargers. (It's possible our S100D has it but is software locked.)

Honestly, you can probably get by at the lower charge rates but it's nice to bump it up if needed. Of course there are lots of Superchargers opening up in Colorado so you could always top off at one if you needed to charge even faster.
 
This is exactly what I was looking for! Thank you so much! Now I just need to figure out how to come to a decision on which charging philosophy I should go with for standard daily charging; charge for a shorter time at a higher amperage, or longer time at lower amperage.
I would just give this one little piece of advice. I've seen enough reports on here for all kinds of Tesla wall or mobile charging equipment that there can be some issues with them getting pretty hot and having problems when run at their maximum current daily. So if you do get a 2nd generation wall connector, I would recommend not always using it at 80A. Turning it down a little in the car to 65 or 70 amps will keep it cooler and probably extend the life of it some.
 
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I would just give this one little piece of advice. I've seen enough reports on here for all kinds of Tesla wall or mobile charging equipment that there can be some issues with them getting pretty hot and having problems when run at their maximum current daily. So if you do get a 2nd generation wall connector, I would recommend not always using it at 80A. Turning it down a little in the car to 65 or 70 amps will keep it cooler and probably extend the life of it some.
That would be my plan. If I wire the Wall Connector to run at 80 amps and software limit it to 70 amps, does the car keep that configuration, or do I need to limit it each time I plug in?
 
That would be my plan. If I wire the Wall Connector to run at 80 amps and software limit it to 70 amps, does the car keep that configuration, or do I need to limit it each time I plug in?
The car will remember the setting. There's a chance it might get reset after a firmware update but I haven't seen that happen recently.
Yes, this, but I will also add that what it does if you change the amp setting while charging is to create a limit entry tagged to that location. So if you go to a public charging station or a friend's house, it will revert back to try the max that the charging station is announcing available. But then back at home, it will go back to the level you set there.
 
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I would just give this one little piece of advice. I've seen enough reports on here for all kinds of Tesla wall or mobile charging equipment that there can be some issues with them getting pretty hot and having problems when run at their maximum current daily. So if you do get a 2nd generation wall connector, I would recommend not always using it at 80A. Turning it down a little in the car to 65 or 70 amps will keep it cooler and probably extend the life of it some.

I'm sure there are probably problems, but we haven't had any. Like I said, I've got 217000 miles on my car, supercharged it three or four times a week, charged it at home at 80 amps for the last four years. Haven't had any problems and still have the original battery. of course, Tesla has slowed the supercharging, and all charging in the last 5 to 10%, but still it works well. The advantage of the 80 amps is less time at heat. The advantage of a lower amperage is maybe it never gets that hot. Seems to be a wash to me. personally I think those 7000 batteries all sharing that 80 amps doesn't get them hot enough to be an issue. The cable on the other hand, it's a good hand warmer! the convenience of having the car be ready sooner was a big deal for us. For years we had two different users of the car most days. Schedules off from one another.
 
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70 is pretty high for residential wiring. Esp a retrofit. I personally wouldn’t go over 48 on a daily basis without a need for quick turnaround.
You are talking about this as if it's some random wire of unknown thickness that already existed in the wall, and someone just on a lark decided to hook a high power appliance to it with no idea what was going on. That's not what this is. Besides, EVERY new circuit that anyone adds is a "retrofit".

This is talking about legitimately installing a fully up to code 100A circuit, with the proper size and type of wire. So for a 100A code compliant circuit, running at only 70A is already being very safe and leaving a lot of margin.

I'm sure there are probably problems, but we haven't had any. Like I said, I've got 217000 miles on my car, supercharged it three or four times a week, charged it at home at 80 amps for the last four years. Haven't had any problems and still have the original battery. of course, Tesla has slowed the supercharging, and all charging in the last 5 to 10%, but still it works well. The advantage of the 80 amps is less time at heat. The advantage of a lower amperage is maybe it never gets that hot. Seems to be a wash to me. personally I think those 7000 batteries all sharing that 80 amps doesn't get them hot enough to be an issue.
You're talking about all this as if we're discussing home charging being hard on the battery. Of course it isn't!

The cable on the other hand, it's a good hand warmer! the convenience of having the car be ready sooner was a big deal for us. For years we had two different users of the car most days. Schedules off from one another.
Sure, it's convenient to have it available for when you need it, but heat cycling and thermal stress is a long time build-up of degradation of materials. So if you don't need that fastest charging speed every single night, you can save some wear on the equipment by not letting it get as hot most days.
 
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I finally got a resolution to my Gen 3 Wall Connector issue. After multiple firmware updates, the one flashing red light “grounding fault” went away, only to be replaced by a three flashing red light “overheat fault”. The glass on the wall connector was pretty warm during charging at that point. By bumping the charging amps down to 20amps I could charge continuously without it cutting off. I called the number in the Gen 3 manual PDF and got put through to the help desk for professional installers. I am not a professional installer. He wanted me to get my electrician back for a third time to recheck his work. I decided that wasn’t going to happen so I called the main Tesla number and selected Energy Products, then Wall Connector on the phone options. They sent out a replacement which I switched out and I’m back charging at 40amps with no issues.

My Gen 3 Wall Connector suddenly started having charging interruptions every hour or two while charging my 2016 Model S 90D. One red blinking light on the connector during the interruptions which points towards a grounding issue. I’ve had the car and wall connector(installed by an electrician) about 6 weeks with no issues. Did a trip last weekend and did some 110v charging in an RV park as well as some supercharges and that following night the problem started.

I just happened to have a Tesla Mobile Service tech out yesterday doing an unrelated repair and he said the problem is not with the car from what he could see. He did say that is should be charging at 32 amps instead of 40amps(50amp breaker) as its bad to charge above that. I found that odd as I’ve never heard that before. I bumped the charging amps down to 32 on the car’s screen but the interruption problem persists. Should my next step be to open up the wall connector and move the dial down to 32 amps from there?
 
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If anyone is looking for a new Generation 2 charger, I have an extra Black HPWC with Elon's signature.
It was part of the referral program and has 2 features not available on the new chargers. PM me if interested.

· Power-sharing with previously installed Gen 2 Wall Connectors.
· High power output (up to 80 amps) for older Model S and Model X equipped with 72A or 80A on-board chargers.
 
I would just give this one little piece of advice. I've seen enough reports on here for all kinds of Tesla wall or mobile charging equipment that there can be some issues with them getting pretty hot and having problems when run at their maximum current daily. So if you do get a 2nd generation wall connector, I would recommend not always using it at 80A. Turning it down a little in the car to 65 or 70 amps will keep it cooler and probably extend the life of it some.
My parents have a Gen 2 on a 100A circuit. They have a 2018 w/ 72A charging, I have a 2014 with dual chargers. When I charge there, I dial it back to 56A (80A/sqrt(2)=56A). Since resistive heating is proportional to the square of the current (P=I*V, V=I*R, P=I*(I*R)=I^2*R), a small decrease in charge current has a significant decrease in heating throughout the system.

I try to keep my charge current over 40A whenever possible to test the secondary charger and split the load (and heating) across both chargers.
 
Hey, everyone. I recently bought a 2015 P85D with the dual charger upgrade. Naturally, due to my stubbornness, I'd really like to find a Gen 2 HPWC to take advantage of the upgraded chargers. I've seen differing opinions about the benefits of higher vs lower amperage charging, but my question is this: does anyone know how load is distributed across the two chargers? For example, if I charge at 40 amps, will one charger take all 40 amps, or will it split the load 20/20?

Also, with all of the newer gen HPWCs maxing out at 48 amps, as the gen 1/2 HPWC start to fade away, does that make the charger upgrade pretty much useless?

I have a brand new in the box gen 2 HPWC for sale with the 21ft cable option. Let me know. You can PM or just text me at 425 243 7088.

Thanks!
 
I have a 2014 Model S and a Gen 1 HWPC. I just installed it on a 60A breaker. When I set the dip switches to 60A, the car only charges at 12A. However if I set the dip switches to 50A, the car will charge at the correct rated 40A. Any ideas what is going on here? The HWPC is giving no error lights or anything.