High Amperage charger

High Amperage charger


I'm looking to purchase a wall connector for my 85D model S.
I don't know whether I need the 60 or 90 amp model.

Where can I find out if I have the, High Amperage charger upgrade?

SpaceGhost | 6 March, 2018

I think you just have to look at the charging screen in the car... There is a place where you set the maximum amperage based on location. I have a MS90D that goes up to 72 amps. I believe the cars without the upgraded charger only go up to 40 amps.

murphyS90D | 6 March, 2018

My pre-refresh S90D goes up to 80 amps.. It was 40 amps when I got the car but I added the optional second charger. Post refresh cars do it differently.

Anthony J. Parisio | 6 March, 2018

SpaceGhost is right.

jordanrichard | 6 March, 2018

Rahul, who are you buying this car from? If it is the original owner, ask them if they ordered the optional dual charger.

rahul | 6 March, 2018

Thanks SpaceGhost, murphy & Anthony i will take a look at that screen.

@jordanrichard this was bought new from the dealer in 2016, I couldn't remember about the optional equipment so i took a look at mytesla page and still there was no mention.This is why i ended up asking here.

Thanks again for the help.

Rocky_H | 6 March, 2018

@rahul, Yeah, what @SpaceGhost mentioned--set the amps up or down on the charging screen, but the important part is to do that while you are NOT hooked up to a charging connection. If you are not hooked up, then it will let you turn it up to whatever the capability of the car has to see what's there. But if you are connected to a charging cable, then the supply equipment is sending a signal of how many amps are available, and you will only be able to turn it up to whatever that maximum is, maybe 30 or 40 amps, and you can't see what the car is capable of.

rahul | 6 March, 2018

@Rocky_H thanks, i just checked and it's maxed @ 40 amps. So this means it's the standard.

so when i purchase the wall connector, i should use a 60 amp circuit.
but when i upgrade this vehicle the next one will likely have the high amperage charger, so can the wall connector then be upgraded to 90 or 100 amp circuit?

joshualangert | 6 March, 2018

Actually, you need a 50amp breaker and wiring gauge for 50amps for a 40 amp circuit (10% cushion). If you want to skip the Tesla wall connector (and save $500) using the mobile connector and putting in a NEMA 14-50 plug will get you 40 amps charging. Unless you like the ease of the wall connector, then hard wire that onto your 50amp circuit

joshualangert | 6 March, 2018

Sorry 20% cushion. Long day...

tes-s | 6 March, 2018

If you are thinking about the future, put in a 100amp circuit to the wall connector.

That way, your wall connector can put out up to 80amps, and will work fine with your 40amp car. If you get a car that can charge at higher current in the future, you are all set. If you get a second car and want another wall connector, it can be daisy-chained with this one and share the 100amp circuit, dividing the available current between the two wall connectors.

Installation cost of 100amp vs 50amp is not that much different. Same labor, just higher cost for the wire. Assumes your panel can handle 100amps.

Rocky_H | 6 March, 2018

@rahul, The NEC rule is for the constant current level to be 80% of the circuit rating, which is the breaker and wire. So a 50A circuit will provide 40A. Up to you how big you want to go. I found the 40A is plenty fast enough for one car overnight at home charging.

About this:
"but when i upgrade this vehicle the next one will likely have the high amperage charger,"

People seem to get weird ideas about this. Let's say you get a car with a faster 150mph top speed. And then an even faster car with a 200mph top speed. You're still going to drive the same 51mph in the 45mph speed zone on your way to work. Same thing with your charging. As you buy electric cars with bigger batteries or faster onboard charging, you don't move 2X, 3X, or 4X as far from work. You drive the amount of miles that you drive, which doesn't change based on the kind of car you have, and you still sleep the same amount of time, so you still have about 7-8 hours to refill it. So your circuit at home needs to cover for how much you drive, not what kind of car it is.

So the 40A of charging will get you about 30-some miles per hour of charging. That's over 200 miles you can refill every night. Who cares if your future cars have faster charging. I agree that's useful sometimes on the road if you need to hit up a charging spot for a couple hours and want the most miles you can get, but for at home, where you have that overnight convenience, it doesn't generally matter.

But for future upgrades, the part that is difficult/costly to change is the wire in the wall or conduit. So if you want to put in slightly oversized wire, then that's OK. Then, you could change to a larger breaker if you want in the future. Also, if you want to plan for a second electric car, the wall connectors have the ability to smartly charge share. So you could maybe go for a 60 or 80 amp circuit to run two wall connectors, and they will shift charging as each car needs.

Anthony J. Parisio | 7 March, 2018

If possible I would install a 100 AMP service and set the HPWC to 100 AMP. The car will only pull 40 AMP but you will be ready for the future.

tes-s | 7 March, 2018

"So if you want to put in slightly oversized wire, then that's OK. Then, you could change to a larger breaker if you want in the future."

What would be the advantage of starting out with a smaller breaker, and then putting in a larger one later? Why not simply put in the larger breaker?

pnajar | 7 March, 2018

It makes the most sense to put in the large breaker and the larger wire. My current car, P85D, uses the high 80A charging. On occasion I’ve charged a neighbors Model X at 40A. The Teslas only draw what they need.

SpaceGhost | 7 March, 2018

The HPWC has a selector inside that is set to match the circuit and breaker size. The current models support up to a 100A circuit, or 80A charging. I think you can find the owners manual online if you search for it.

avesraggiana | 7 March, 2018

@SpaceGhost. There's an installation guide as part of your list of documents in your MyTesla account. I was going to print out a copy of it to give to my electrician but he just informed me that he's already installed "a lot" of these HPWCs.

bp | 7 March, 2018

For an 85, you really only need a 40A charger or a 14-50 for overnight charging.

The 80A charger is really only needed if you're trying to charge faster than overnight, such as on a road trip, if you want to recharge quickly mid-day. Though most destination or public chargers won't provide more than 40A, so even if you have the onboard capability to charge at 72A or 80A, you may have to hunt around to find a destination/public charger that can support that.

We've had our S P85 since early 2013 - and the only time we needed more than 40A was after we drove the car during the day, and needed to quickly recharge before doing a road trip that night. That was in 2013, before there were any superchargers - and we had to get enough charge before we left home to make it all the way to our hotel destination.

Since the supercharger network was deployed - haven't needed it.

And our S P85 (with an 80A onboard charger) is now using a 14-50 outlet, with our S 100D connected to the HPWC.

Unless you need to recharge quickly during the day, save your money at home - install a 50A circuit and use either an HPWC, UMC or 14-50 connector - that's fast enough to recharge an 85 overnight.

Tropopause | 7 March, 2018

Just to be clear, Tesla has configured Model S with four different charging options through the years with different names:

Older S vehicles had:

- Single charger 40 amps. (requires 50 amp breaker)
- Dual chargers 80 amps. (requires 100 amp breaker)

Newer S vehicles have:
- Standard charger 48 amps. (requires 60 amp breaker)
- High Amp charger 72 amps. (requires 90 amp breaker)

Of course you can utilize a lower amp breaker if you don't want to take advantage of your dual-chargers or high-amp charger's higher output.

blacktape242 | 7 March, 2018

Tropopause - thanks for that info i just got a wall charger for a reward and want to install it rather then having the charger that came with the S.

Rocky_H | 7 March, 2018

@tes-s, Quote: "What would be the advantage of starting out with a smaller breaker, and then putting in a larger one later? Why not simply put in the larger breaker?"

Reasonable question. The "advantage" I'm referring to is based on I wouldn't assume that everyone has gigantic 400+ amp main electrical services with tons of spare capacity to throw in an extra 100A circuit without a thought. My whole house runs on a 125A, so adding a 100A right off the bat when it's not needed isn't always the easiest or best thing.

So, my thought was that it probably is fairly easy and cheap to put in the 50A breaker. And then if there are some other plans with the house of adding a circuit for something else in a few years, you haven't unnecessarily used up the capacity with the huge car charging circuit you didn't need.

Changing it to a 100A later might require expansion of the main service, adding a sub-panel, etc. Who knows? That can run into significant money, so I just wouldn't recommend that $$$$ to someone to do up front if it's not needed.

tes-s | 7 March, 2018

In that case, may as well put in the largest circuit supported, with appropriately sized wire. No need for the larger wire since replacing it in the unlikely event of a panel and service upgrade would be a rounding error.

Rocky_H | 7 March, 2018

@tes-s, Yes, if doing a wall connector from the start anyway, that's probably true. I was kind of forgetting that part and reverting to the old advice where people would just put in a 14-50 to use the included mobile cable first, without having to buy anything new. But then later, might get a wall connector at a higher level, and running wire is usually the complicated expensive part to redo later, so you oversize that from the start to save migraines later.