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Question regarding max amperage capability of the "old" HPWC.

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I took delivery of my S90D at the end of March. In preparation for delivery I arranged for an electrician to pull the line from my panel in the basement to the garage and install the HPWC. I've used this electrician previously for reno work so am confident in the quality of their work and value for the $. They've installed "dryer" plugs for other customers but never a Tesla wall connector. They consulted with others(electricians with tesla install experience)and ended up having no problems at all. Sorry for the lengthy preamble but my question is about the max amperage the wall connector can provide and if it is set up properly. The line the electrician pulled is on its own 100 amp breaker from my main panel, to its disconnect box beside the wall connector in the garage. When I plug in the charging cable and watch the charging "stats" either on the app or at the screen in the car, the amperage never strays above 40 amps. Is that all I should expect from the HPWC? Or are there other settings one can adjust on the HPWC itself to raise the amperage? Just wondering if I'm getting the most from my home charging set up.
 
Check to make sure the dip switches in the HPWC are set correctly (consult the manual). Also, check to make sure your Tesla is set to 80 amps (or that you have the ability to switch from 40 amps). If the install was done correctly, sounds like a dip switch issue. Should be able to put them into the 100 amp configuration and you should be good.
 
Check to make sure the dip switches in the HPWC are set correctly (consult the manual). Also, check to make sure your Tesla is set to 80 amps (or that you have the ability to switch from 40 amps). If the install was done correctly, sounds like a dip switch issue. Should be able to put them into the 100 amp configuration and you should be good.

Ok. I will have a look at the dip switch settings info in the manual and go from there. I do know that I cannot increase the amperage any higher than 40 amps on either the app or the screen in the car.
 
HPWC.png
definitely the dip switches - I did the same think when I installed ours. -- Make sure you kill the power before you pull the cover off... safety tip of the day...
 
Couple other things to check would first try to manually change the 40amps to 80amps on the screen. Second would be to double check and make sure you have the dual chargers installed if they didn't install the dual chargers you won't get above 40amps.
 
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definitely the dip switches - I did the same think when I installed ours. -- Make sure you kill the power before you pull the cover off... safety tip of the day...
OP should use the DIP switch settings in his/her manual (not necessarily this picture) as they've changed (ie, this picture shows the later one that replaced some high current settings with low current ones).

Since this was the electrician's first HPWC, it sounds like this "pro" didn't RTFM (1/2 demerit point!), or the OP's car doesn't have dual chargers.
 
You guys are right on that one....no dual chargers.. Guess the debate now begins as to the merit of having it installed......fun times!
Had dual chargers installed three weeks ago and wish I did it sooner. Drive about 80-100 miles per day and having that quick 60+ m/h charge rate makes a big difference for me. All depends on your usage. Looking forward to this being very useful at destination chargers for road trips in the future.
 
Dual chargers with 80amp HPWC is very fast. In fact it's so fast that I don't even keep track of how long it charges after our longest 100+mi drives... rough estimate would be about 60 miles per hour recharge?

**Also I believe that the "old" HPWC can only handle up to 80amps of current... When I had my electrician install mine, he said anything higher would be a potential hazard (putting in a 100amp breaker in an 80amp rated unit).

The new HPWC however I believe CAN handle up to 100amp breaker, but unless you have a brand new/refreshed Model S (or will after this one) then the 100amp breaker would be of no use, and the 80amp would be fine.
 
The upgrade from single charger to dual chargers is a "no brainer" if you drive more than 150 miles per day. When you arrive home and need to head out again, one can charge for another hour and 45 minutes and basically have a full charge.

If you install the dual chargers, when plugged into the HPWC "old one" the car will first charger at 40 amps and then ramp up to 80 amps as the second charger is activated.

I found the installation to by very easy and the manual with the HPWC included all the necessary info for a successful install.
 
**Also I believe that the "old" HPWC can only handle up to 80amps of current... When I had my electrician install mine, he said anything higher would be a potential hazard (putting in a 100amp breaker in an 80amp rated unit).
Your electrician is wrong. All versions of the HPWC could supply 80 amps, provided they were connected to a 100A circuit (wiring and breaker). Circuits are rated for intermittent use, but charging is considered a continuous load, so the circuit has to be up-sized to 125% of the charge current (or, another way to consider it, you can only charge at 80% of the circuit's rating). If you are charging at 80A, you need a 100A circuit.

The new HPWC however I believe CAN handle up to 100amp breaker, but unless you have a brand new/refreshed Model S (or will after this one) then the 100amp breaker would be of no use, and the 80amp would be fine.
I'm not sure what you mean. Any properly installed HPWC on a 100A circuit can deliver up to 80A to a dual-charger, pre-refresh S. Post-refresh cars can only pull 72A max (with the optional high current charger), so they need a 90A circuit (or higher).
 
Your electrician is wrong. All versions of the HPWC could supply 80 amps, provided they were connected to a 100A circuit (wiring and breaker). Circuits are rated for intermittent use, but charging is considered a continuous load, so the circuit has to be up-sized to 125% of the charge current (or, another way to consider it, you can only charge at 80% of the circuit's rating). If you are charging at 80A, you need a 100A circuit.


I'm not sure what you mean. Any properly installed HPWC on a 100A circuit can deliver up to 80A to a dual-charger, pre-refresh S. Post-refresh cars can only pull 72A max (with the optional high current charger), so they need a 90A circuit (or higher).
Good thing I'm not an electrician then!
 
The only merit is "good looks". A dryer plug will do the same job with your mobile charger.

Not really. If you don't want the hassle taking out the UMC (mobile charger) every time you come home and put it back in the car when you leave, you want either a 2nd UMC (which is what I did, because back then the HPWC was $1200) or a HPWC so the cable will be waiting for you

Some owners recommend branching off a NEMA 14-50 outlet so you can switch to the UMC if the HPWC fails.
 
I've read a lot of posts on how much people have paid to have their hpwc installed and how much they had a 50amp installed for regular 240 charging. I know we've purchased expensive cars but that doesn't mean we should get ripped off by an electrician. The install for a reg 50 amp should cost around $300. If the run isn't long it's a matter of balancing the loads and running a conduit. I was lucky my panel is in the garage, my friend had to go through a wall and run roughly 15 feet and it only cost him $300 by an insured electrician it was an hour and a half job, he had to pay 30 min travel as well. I highly recommend against telling any electrician you have a tesla and are planning on installing a charger for it, that automatically hikes the price. When installers hear tesla they see $$$.
You should hire an insured electrician on an hourly basis and you will be surprised on how little the install for hpwc or just a regular nema plug costs.
 
I've read a lot of posts on how much people have paid to have their hpwc installed and how much they had a 50amp installed for regular 240 charging. I know we've purchased expensive cars but that doesn't mean we should get ripped off by an electrician. The install for a reg 50 amp should cost around $300. If the run isn't long it's a matter of balancing the loads and running a conduit. I was lucky my panel is in the garage, my friend had to go through a wall and run roughly 15 feet and it only cost him $300 by an insured electrician it was an hour and a half job, he had to pay 30 min travel as well. I highly recommend against telling any electrician you have a tesla and are planning on installing a charger for it, that automatically hikes the price. When installers hear tesla they see $$$.
You should hire an insured electrician on an hourly basis and you will be surprised on how little the install for hpwc or just a regular nema plug costs.

It also depends upon whether you need to replace your old panel, either because is one of the unsafe ones or it's just way too small (100 amps for example), add a sub panel, the amount of conduit needed, and if there are any other circuits to be run (since the electrician is already out there). Not telling them about the Tesla is a good idea, but not very practical when the car is sitting in the driveway :)