Juice box 48

[Alan M]

My LR 2021 Model 3 charges at 40 amps. I have a Juice Box 48 and can’t get the car to charge at 48 amps. I changed the setting in the car on the charging that was at 5 amps to 48 amps which is what someone suggested but that didn’t work. What am I doing wrong?

 

[jwharnish]

My LR 2021 Model 3 charges at 40 amps. I have a Juice Box 48 and can’t get the car to charge at 48 amps. I changed the setting in the car on the charging that was at 5 amps to 48 amps which is what someone suggested but that didn’t work. What am I doing wrong?

What size breaker is the Juice box hooked up to? 50amp or 60amp?

 

[Alan M]

My LR 2021 Model 3 charges at 40 amps. I have a Juice Box 48 and can’t get the car to charge at 48 amps. I changed the setting in the car on the charging that was at 5 amps to 48 amps which is what someone suggested but that didn’t work. What am I doing wrong?

What size breaker is the Juice box hooked up to? 50amp or 60amp?

I just checked, and it is a 50.

 

[jeremymc7]

Well that’s your problem.

60A gives yo 48A
50A only gives you 40A

If you have wiring to support 60A you can swap to a 60A breaker.

The likely hood though is it’s unlikely higher rated wire was installed with a lower rated breaker. But ehh it happens.

 

[Alan M]

Well that’s your problem.

60A gives yo 48A
50A only gives you 40A

If you have wiring to support 60A you can swap to a 60A breaker.

The likely hood though is it’s unlikely higher rated wire was installed with a lower rated breaker. But ehh it happens.

Thank you. The electrician followed the instruction. Oh well, another expense, but I guess it is worth it.

 

[jwharnish]

Thank you. The electrician followed the instruction. Oh well, another expense, but I guess it is worth it.

40 amps works well for home charging. Changing everything out to get 48 amps would only achieve a couple more mph charge rate. I'm not sure the Model 3 can charge at 48 amps, I thought the max for level 2 charging is 44 amps?

 

[Alan M]

40 amps works well for home charging. Changing everything out to get 48 amps would only achieve a couple more mph charge rate. I'm not sure the Model 3 can charge at 48 amps, I thought the max for level 2 charging is 44 amps?

So much involved. Bought the JB48 intentionally to have the most power, looking to the future. Then I find out PSEG doesn’t give a rebate (I called before actually buying it and was told they were working on it), for that model (32 and 40 they do). The extended range Model 3 can go to 48 amps; the charge screen in the car when I saw it this morning showed 0/48 amps. So I guess if I was in the car during charging it would show 40/48. The app shows 40/40 amps but is charging it says at 41 miles an hour while I read at 40 amps it charges at 33 miles an hour. I am assuming at this moment that the app would show the accurate number of amps used. Next charge I will go into the car to see what the charge screen shows. Going to read the installation instructions when I get home, may call the company if paperwork not clear. New to this, and did not expect an issue.

 

[Alan M]

Thank you. The electrician followed the instruction. Oh well, another expense, but I guess it is worth it.

Just looked at the instructions and it says if using a plug, use a NEMA 14-50 outlet and doesn’t say what size breaker to use. It seems they are saying to use a 50 based on the plug. Seems logical to me, but am I thinking correctly?

 

[jjrandorin]

40 amps works well for home charging. Changing everything out to get 48 amps would only achieve a couple more mph charge rate. I'm not sure the Model 3 can charge at 48 amps, I thought the max for level 2 charging is 44 amps?

A LR or Performance model 3 can absolutely, positively charge at 48amps, given the correct charging infrastructure. "Right charging infrastructure" = Device capable of passing through 48amps, and appropriate breaker / cabling.

With that being said, there are very few instances where the difference between someone charging at 40amps on a 50amp breaker and 48 amps on a 60 amp breaker will make any impactful difference at all in a persons ownership / charging experience.

I get wanting "the fastest it can go" (I really do, I did that too back when I got my model 3 performance in 2018). Given that this OP is charging at 40amps on a 40amp breaker, I wouldnt pay anything to change it, though.

Here is teslas estimation of charging speed. The difference in 40amp vs 48amp is 37mph to 44 MPH. The number of times that 7 additional miles per hour is going to make some difference in the OPs charging experience is likely "almost never" or "never".

 

[jjrandorin]

So I guess if I was in the car during charging it would show 40/48.

Nope, it would show 40 / 40

The "charger" is actually in the car. It announces to the equipment how much power it can take, and the wall connector will provide power up to its available limit.

There is also almost zero reason to have a juicebox 48 over a tesla HPWC, especially since its more expensive than the tesla HPWC. To charge at the speed you are asking about, you would want to hard wire that device, not use a 14-50.

Still, see my previous post. None of this is worth 7 miles per hour charge rate.

 

[Rocky_H]

Just looked at the instructions and it says if using a plug, use a NEMA 14-50 outlet and doesn’t say what size breaker to use. It seems they are saying to use a 50 based on the plug. Seems logical to me, but am I thinking correctly?

Yes, a 14-50 outlet would use a 50A outlet. That naming convention is that the first number is the code for the type of outlet, and then the second number is the number of amps it is.

There is also almost zero reason to have a juicebox 48 over a tesla HPWC, especially since its more expensive than the tesla HPWC. To charge at the speed you are asking about, you would want to hard wire that device, not use a 14-50.

Yes, that is very strange to get a Juicebox 48 if you are going to use a 14-50 outlet. You wouldn't be able to use it at 48A then. That would require a 60A circuit, which a 14-50 outlet can't be on.

 

[jeremymc7]

40 amps works well for home charging. Changing everything out to get 48 amps would only achieve a couple more mph charge rate. I'm not sure the Model 3 can charge at 48 amps, I thought the max for level 2 charging is 44 amps?

Yeah I was thinking the exact same thing. I just (previously) didn’t want to say anything. It’s their money after all. If they want to pay twice for an extra trickle.

 

[Alan M]

Nope, it would show 40 / 40

The "charger" is actually in the car. It announces to the equipment how much power it can take, and the wall connector will provide power up to its available limit.

There is also almost zero reason to have a juicebox 48 over a tesla HPWC, especially since its more expensive than the tesla HPWC. To charge at the speed you are asking about, you would want to hard wire that device, not use a 14-50.

Still, see my previous post. None of this is worth 7 miles per hour charge rate.

Hi, it is hard wired, I was just quoting the instructions where it said what the plug would be and then why when hard wired the electrician used the 50 amp breaker. I wish he had known to use a 60 amp breaker.

 

[jjrandorin]

Hi, it is hard wired, I was just quoting the instructions where it said what the plug would be and then why when hard wired the electrician used the 50 amp breaker.

If I were you, I would check for information of what the electrician stated they were going to do, and get them back out there. You will need a 60amp breaker at a minimum (to set it up to charge at 48amps), and the wiring may or may not have been run that supports that. Its either a fairly easy (for an electrician) breaker change, or, a breaker change and re running some wiring (provided your panel can support 60amp vs 50 amp charging for your EV)

Who pays for that depends on what the agreement you had with them was. If you were clear that you were expecting to be able to charge at 48amp speed and it was EV charging (thus you can only charge at 80% load for continuous charging), then perhaps its on the electrician.)

If it was "i want to connect this thing for fast charging", and they gave you a price for "connecting that thing for fast ev charging" then its likely on you.

 

[jwharnish]

A LR or Performance model 3 can absolutely, positively charge at 48amps, given the correct charging infrastructure. "Right charging infrastructure" = Device capable of passing through 48amps, and appropriate breaker / cabling.

With that being said, there are very few instances where the difference between someone charging at 40amps on a 50amp breaker and 48 amps on a 60 amp breaker will make any impactful difference at all in a persons ownership / charging experience.

I get wanting "the fastest it can go" (I really do, I did that too back when I got my model 3 performance in 2018). Given that this OP is charging at 40amps on a 40amp breaker, I wouldnt pay anything to change it, though.

Here is teslas estimation of charging speed. The difference in 40amp vs 48amp is 37mph to 44 MPH. The number of times that 7 additional miles per hour is going to make some difference in the OPs charging experience is likely "almost never" or "never".

Thanks for the correction on the charge rate. Looks like I was seeing 44 and thought that was amps and not mph.
Still would call it a day and go with the 40amp charge rate. 8 hours of charging overnight would still get you around 280 miles, which for most would be more than sufficient. I'm using a 30amp plug for 21 mph rate. Never had a problem with having enough charge in AM when I did trips.

 

[Alan M]

Ok, to start with, it is now charging at 48 amps. Had electrician change 50 amp breaker for a 60 breaker. Wiring he put in matches the charger, so is a 6 when it needs a 4 to match the breaker. Still charged at 40 amps. I called Enel X and spoke with the tech department. Bottom line, he sent new instructions for wiring and for the voltage. Said that the 50 amp breaker would have been fine and worked. So a little while ago I checked on it and low and behold, charging at 48 amps.

 

[Nobodytoo]

Can you tell us what exactly yuo did. Did you change the #6awg wire to #4awg wire?

 

[paulsalem]

If you have a 60a breaker connected to the JBHome via Nema14-50, how does the JB know to only pull 40a instead of 48a?

 

[jeremymc7]

Draw on many electronic devices is deigned for 80% of plug rating, baring peaks. 14-50 is 50A. 80% is 40A. But there should also be programming in/on the box. Not sure why there is a 60A breaker on a 50A line. You don't want to push a 50A line to 60A before breaker trips. But JB should have smart settings/sensing.