Question about HPWC

[Mrwatchdawg]

*** don't kill me if it's been asked before! I tried searching ***

I bought a HPWC and was going to get it installed next week. What should it be installed at? I keep hearing anything from 20 amps to 100 amp breaker.

What is ideal? Also, what is the highest amperage that the Mode S 75d will charge at? I ordered a 2017 which should be delivered in 2 weeks or so.

 

[AEdennis]

*** don't kill me if it's been asked before! I tried searching ***

I bought a HPWC and was going to get it installed next week. What should it be installed at? I keep hearing anything from 20 amps to 100 amp breaker.

What is ideal? Also, what is the highest amperage that the Mode S 75d will charge at? I ordered a 2017 which should be delivered in 2 weeks or so.

If you didn't order the high amp option, 48 amps on newer S. Which means, install a 60Amp wire that will run at 48amps... 100A breaker is pretty pricey on long runs.

 

[Mrwatchdawg]

What does the standard charger that comes with it charge at? 20 amps?

Appreciate the reply. I guessi do a 60. I wanted high amperage charger but now they don't offer it apparently.

 

[boaterva]

What does the standard charger that comes with it charge at? 20 amps?

Appreciate the reply. I guessi do a 60. I wanted high amperage charger but now they don't offer it apparently.

The standard charger is 48 Amps. The 'High Amp' charger is 72, and is still offered on the 'higher end' models (100D, P's). Part of the assembly line simplification process. Another reason to install a 100 Amp circuit is if you ever want to have two HPWC's for load sharing to charge two cars at the same time. (See my signature for my install; always a good idea to future proof if you are thinking ahead, but, yes, if can be pricy. But less than redoing it later.)

 

[boonedocks]

If you are going to be in your home for the foreseeable future, I would recommend 100 amp service. It will full proof your today and future charging needs. You may buy an additional Tesla or upgrade to something yet unknown and wished you had gone with the higher amperage down the road. HPWC are daisy chainable and can share the load. If you choose a lower amperage you will be severely hampered if you are in that situation. If it is and will be your only EV and you may be moving, 60 amps is all I would do. 80% of 60 would give you your new Tesla's 48 amp service

 

[TexasEV]

Why did you order a HPWC if you don't know that you need higher amp charging? You could have just had a NEMA 14-50 outlet installed (50A circuit) and charged at 40A which is fine for almost everyone for overnight charging. If you're going to the extra expense of a HPWC, then at least install it on a 60A circuit so you can take advantage of the car's 48A charger. (Unless you paid extra for a 72A charger in the car, you won't get any benefit from installing more than a 60A circuit.)

 

[animorph]

The included charger is 40A, using a 14-50 plug on a 50A circuit.

The HPWC can use just about any circuit amperage up to 100A. It has an internal adjustment that is set to match the breaker size. That might be useful if your electrical panel can only support 30A more. It can also share one circuit with other HPWC's. So running a high amperage circuit now might set you up for two Teslas later.

You have to do a load calculation to figure out how many amps your electrical panel can spare for a new circuit. And you need to have some free space in the panel for the new breakers, or a plan to replace an existing circuit. We were able to disconnect an unused stovetop circuit (we use a gas stovetop) and had just enough capacity for a 100A charging circuit. It will be shared by the current 72A Model X and a Model 3 in the future, using two HPWC's.

 

[bob_p]

For 2017's the standard charger is 48A.

On a 14-50 circuit, you'll only be able to get 40A - which is enough to fully charge overnight (even a 100 battery pack).

A 14-50 circuit is less expensive to install. When we received our new S 100D in March, we shifted our 2012 S P85 over to the 14-50 outlet in our garage, and instead of ordering a second HPWC, we ordered Tesla's 14-50 charging cable and the cable organizer - and leave that cable plugged into the wall all of the time on that side of the garage. Even though we have an HPWC that can charge at 80A on the other side of the garage, we haven't found any need to charge the P85 faster than 40A at home.

If you have the additional power and the cable run is short, it might make sense to install an HPWC on a 100A circuit. But if that starts getting expensive, a 14-50 outlet will likely be much less expensive - and should be fast enough to handle home charging, especially when Tesla adds more urban superchargers, that you could use if you ever need a much faster charge.

 

[Silverstreak]

Why did you order a HPWC if you don't know that you need higher amp charging? You could have just had a NEMA 14-50 outlet installed (50A circuit) and charged at 40A which is fine for almost everyone for overnight charging. If you're going to the extra expense of a HPWC, then at least install it on a 60A circuit so you can take advantage of the car's 48A charger. (Unless you paid extra for a 72A charger in the car, you won't get any benefit from installing more than a 60A circuit.)

THIS, nema 14-50 plenty for 95% of folk.

 

[Mrwatchdawg]

So the difference between HPWC and the 14-50 is just 8 amps.

The reason I bought it was because the sales guy made it seem that it charges twice as fast as the one that comes with it and that it was truely needed.

 

[Silverstreak]

Only if you have dual chargers in car and your house can handle the 80 amp draw.

 

[animorph]

I think the problem with 14-50 will be if you need to charge two cars. Two HPWC's can share a single circuit of virtually any amperage. Two 14-50's will require two 50A circuits, which may be too much for the electrical panel. Hopefully many of us will have two (or more) EV's in the future. On the other hand, you may be able to repurpose the 14-50 circuit to supply an HPWC or several with a little preplanning. Certainly a 14-50 socket is cheaper than an HPWC for now.

I like having the mobile charger always in the car, just in case. At that point the HPWC cost is about the same as a second mobile charger, more flexible, and slightly to significantly faster.

 

[Silverstreak]

I have an extra mobile charger, one I keep in car. If I move, then I just unplug and take with me. One Tesla is perfect with the Nema 14-50 plug. Usually just takes a couple hours to bring it to my daily level of 70%

 

[TexasEV]

So the difference between HPWC and the 14-50 is just 8 amps.

The reason I bought it was because the sales guy made it seem that it charges twice as fast as the one that comes with it and that it was truely needed.

It charges almost twice as fast (72A vs 40A) only if you have it on a 90A circuit so you can draw 72A AND your car has a 72A charger. But why do you need to charge that fast at home? As long as it charges overnight, does it matter if it finishes at 2AM or 6AM? The 72A charger is more useful when traveling, if you find a destination charger at 72 or 80A and you're having to share it with another guest.

 

[Mrwatchdawg]

well and the thing is since i have a 75D the HPWC wont make a difference regardless, so might as well just return it in this case.

The car will be plugged in overnight everyday and especially since the normal charger that comes with it will charge at 40 amp and the only advantage the HPWC will do is an extra 8 amps.

Not worth keeping it.

Correct me if i am wrong but returning it sounds like a good deal. Plus i dont see another EV getting added to the stable unless they come out with another SUV (wife loves her RR over the Model X, which i think is stupid)

 

[Silverstreak]

that is what I would do, no advantage at home. Just get a Nema14-50 put in and get an extra portable charger, if you are so inclined.

 

[TexasEV]

Think hard before you get an "extra portable charger" (UMC). Some people think using the UMC (universal mobile connector-- not charger) means you have to disconnect it and take it with you every day. That's not the case. Mobile is a capability, not a requirement! Most keep it plugged in and hanging on the wall, and only take it down if they're going on a trip. "Just in case" just never happens-- you don't need the UMC for superchargers, or J1772s, or HPWCs. The only time you would use it is to plug into an outlet. You would know if you're going somewhere that might need plugging into an outlet-- otherwise leave it in your garage.

 

[gabeincal]

I'm putting in a HPWC right now in my house. Went with 100A breaker and wire to match 80A continuous. I will dial it down for now as I only have a single charger in the car, but eventually I want to be able to dial it up to 80A in the future should I buy a higher charge rate car. Just to future-proof my investment...

 

[tga]

It charges almost twice as fast (72A vs 40A) only if you have it on a 90A circuit so you can draw 72A AND your car has a 72A charger. But why do you need to charge that fast at home? As long as it charges overnight, does it matter if it finishes at 2AM or 6AM? The 72A charger is more useful when traveling, if you find a destination charger at 72 or 80A and you're having to share it with another guest.

Some people have time of use plans with narrow windows for cheap charging.

If you have nearly free electricity from, say, 2-6am, you want to be able to do as much of your charging as possible in that window, which could argue for 72/80A.

I've charged in the wild at 80A a few times. Once when I needed a quick boast to be sure I could get to the supercharger, and a few times while having lunch with friends in Brattleboro. Yes, I could go hang out at the supercharger after we eat, but I'd rather charge while eating. One of the 80A free Clipper Creeks in the town garage can put back more range during lunch than I need to get home.

But at home, I charge at 24A (no time of use yet).

 

[zjfk2]

I wish I had wired my place at 100 amps when I had my clipper creek charger installed for my leaf prior to my Tesla purchase. The electrician talked me out of of future proofing it. The clipper creek works fine for my current use with one tesla at 32 amps charging, but I'm contemplating a pacifica hybrid for my wife or keeping my model 3 reservation for her. If i had run 100 amp service to my carport, I could easily charge 2 cars with it