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EMotorWerks JuiceBox Pro 75 and Tesla S

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I am new to Tesla and this forum. I apologize in advance if this has been posted but could not find anything on point. I have another EV that I had a JuiceBox Pro 75 installed in my home. This is a direct installed unit to our electric system. They unit is supposed to deliver 75 amps in charging, vs the more standard 40amps.

Upon receiving my 2016 Tesla S 90D I noticed that the settings in the Tesla limit the charing to 40amps. I cannot increase this to the higher levels.

Some questions:

1) Has anyone run into this situation before and is there a fix?

2) Are there settings that need to be adjusted on the Tesla or on the Juice Box to achieve the higher charging rate (even at 60amps would be welcomed)

3) I have to use the Tesla adapter plug converting from commercial unit to Tesla plug unit. Is the adapter limiting the charge limit and if so are there higher end adapters.

I appreciate any solutions or directions that one can point me to. I have opened a claim with EMotorWerks to see if they have dealt with this.
Yes, I have a 2014 S85 that also only has the single 40A limited charger onboard. I've looked at that $2,000 option for the second charger, and it's just not worth it. I would never ever have any need for it overnight at home. The only place that really can be useful is on some routes that are incomplete as far as Supercharger coverage, and you need to bridge the gap with a high amp AC wall connector that a business has put in somewhere. @JFeeler you live in Boise, as I do, and we have a little unique spot in having the largest hole in the north american Supercharger network next to us with some very common routes that are not Supercharger connected and have charging opportunities that could make use of this. See if these would be useful to you or not:

If you drive from Boise to Bend Oregon often. The normal shortest route is US highway 20 through Ontario and then Burns. With 40A charging, it will require about 3 and a half hours of charging in Burns. And it's Burns. There's not that much to occupy 3 hours there. But the Chamber of Commerce building there does have an 80A charger on the back of the building, so if you have the second charger in your car, that could reduce it to about an hour and a half. That's not too bad if you plan a lunch stop there.

The alternate way to go, which I've done is Boise to Baker City, so you can fill up much faster at the Supercharger and then go through John Day to Bend on US highway 26. It's still really tight to do that leg without stopping when the weather is warm, but in cold, no way. So there is a high power charger in John Day, which I haven't used yet.

The other one, which really shocks me is that the pretty common route from San Francisco to Boise is not Supercharger complete. It's US highway 95 from Boise down to Winnemucca. Northward can just barely be done in one shot when it's warm, because it's downhill, but not going South. I've done the South way, and there is a casino at McDermitt that has a high amp wall charger there. I could only use 40A of it, but with careful driving and nice weather, and a full 1 hour stop for lunch there, it was doable. In cold, it would be 2 hours or more.

So if you do either of those routes often, it might be worth it, but for $2,000, you can rent a vehicle several times, and I would expect that within another couple of years, they may get those filled in with Superchargers, and then it's back to not worth it for anything.
Rocky H and Braxus

Thanks for the replies. I did confirm with the makers of Juice Box that there was a 40amp limit on their device with the MS. Likely the adapter. They were quick to indicate as Tesla changes the configuration my 75 amp unit will support. I guess the X has higher charging options. Not sure what the M3 has.

Appreciate the feedback.
This doesn't sound right:
  • The J1772 adapter does not have a limit on it: it's a purely passive (mechanical) adapter, so neither the car nor the chargepoint can actually tell that you are using one.
  • The communication protocol on the original Tesla HPWC and J1772 are exactly the same, so the car can't tell whether you are using an HPWC set for 72A or a standard J1772 offering 72A. (newer HPWC is slightly different, but there's a lot of old HPWC around and new cars still charge correctly with them).
You haven't confirmed whether your Model S is the facelift or original (black 'nose') version. If it's facelift, there's a mystery why you aren't getting the 48A such cars are supposed to get; if pre-facelift and 2nd charger not fitted, then 40A is exactly what you expect.

Thank you. I am new to Tesla so not familiar with the face lift. The nose of my Tesla is black so based on your comment it may not support the 48amp upgrade. I bought it used and it is a 2016.


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Thank you. I am new to Tesla so not familiar with the face lift. The nose of my Tesla is black so based on your comment it may not support the 48amp upgrade. I bought it used and it is a 2016.
Just noticed you're in Boise too! Yes, from that picture, that is the older version of the car, before the "facelift", when they changed several things.
Regarding the chargers in the car: the older ones, like yours and mine had either the default single charger, which could take up to 40A, or they had the optional second charger added, so it was doubled to 80A. And like @arg was talking about, the J1772 adapter that comes with the car is just a passive piece, so it can take up to 80A or whatever the wall unit is providing. But of course if your car can only pull 40A, then that's all you can get. Mine just has the 40A single charger.

After the facelift update, which came late in 2016, they weren't "single" or "dual" chargers. They were single piece units, but there was a smaller one for 48A or a larger one at 72A. By the time the Model X came, it only had those newer charger options.

You asked about Model 3. At the moment, the long range battery version can take up to 48A. Word is that the smaller battery version will only be able to take 32A.
Yes, that's pre-facelift (the change happened around April 2016 IIRC) so the options when that car was built were 40A standard or 80A dual chargers.

So what you are seeing is perfectly normal. Unless you have an unusual driving pattern, 40A at home should be plenty.

Model 3 also takes 40A maximum. So quite likely you won't ever get around to using the 75A capability you had installed.

However, no need to feel bad about that. If the garage was close to your existing electrical panel, then it probably only cost you a small amount extra for the 75A vs 40A model, and it will run cooler and more reliable than running the 40A unit flat-out. On the other hand, if it did cost you a lot more because it was hard work getting a high-capacity circuit into your garage from the other side of the house, then that money will probably end up well spent when you later become a 2 EV household and split the circuit to get two chargepoints out of it.