New Model X charging limit to 32A

[saz25]

Hi,
I have a new (today) Model X after just trading in my 2015 Model S.
I noticed that its charging at a limit of 32A. I think my Model S was charging at 40A.

Its charging in my garage plugged into a NEMA 15-40.

Did something change or do I need to configure something?
thanks in advance.
Steve

 

[redan]

It's the new Generation 2 Mobile Connector - it has a max output of 32 amps when using the 14-50 adapter. Did you keep your old Generation 1 Mobile Connector? If so, use that and you'll get 40 amps again.

 

[saz25]

That sucks. Why would they do that?

I had to give them my cable when I traded it in. At the time I never thought to keep it.

 

[mknox]

That sucks. Why would they do that?

Many existing NEMA 14-50 outlets are wired to 40 amp circuits (wire size and breaker) which is actually permissible. 32 amps is 80% of 40 (80% rule for continuous loads). There were also a few outlet fires when charging at 40 amps for long periods of times. Continuous loads present heating stress that most other plug loads don't have. This was all likely done by Tesla out of an abundance of caution.

 

[DCGOO]

That sucks. Why would they do that?
I had to give them my cable when I traded it in. At the time I never thought to keep it.

My DS suggested that I might want to keep the gen1 I had with my S, by swapping before I turned in the S. I think I might have used it 3 times during the life of the S.

As to why, just my guess, to eliminate continuing to manufacture two different UMC for the 3/S/X. It is also somewhat smaller and lighter. Most folks install a Wall Connector for home use.

 

[renambot]

Or get the 'corded' mobile connector, it's like the regular one, but with thicker cable and a fixed 14-50 adapter. It gets you 40A.

 

[gnuarm]

Or get the 'corded' mobile connector, it's like the regular one, but with thicker cable and a fixed 14-50 adapter. It gets you 40A.

Huh? Is this because the "corded" mobile connector was designed before the gen-2 Mobile Connector?

Since the problem is with the 14-50 connector being "legit" to use on a 40 amp circuit, does a NEMA 6-50 adapter allow the full 40 amps? The corded 14-50 adapter costs some $500 I believe. Picking up a NEMA 6-50 adapter for the other mobile connector is only $35. I found where the Mobile Connector is still only 32 amps with the 6-50 adapter even though the problem of being connected to a 40 amp circuit doesn't exist with that connector.

I find all the limitations to be difficult to track down. What's up with the HPWC only working at 48 amps while there is a chart which seems to indicate it has potential for supplying up to 80 amps. When can it supply 80 amps and to what? At one of my locations I'd like to have the maximum charging speed I can get. The rest are fine at 32 amps if that's all I can get from a 240 volt outlet.

Unless I can find a way to get more than 48 amps out of a HPWC, I think I'm going to use a 14-50 outlet with an HPWC which should let me get 40 amps charging my Tesla without unrolling the mobile connector and an outlet to charge other BEVs and power other devices without running multiple circuits. But I need two referrals to get the HPWC for free, lol!

 

[Webeevdrivers]

Huh? Is this because the "corded" mobile connector was designed before the gen-2 Mobile Connector?

Since the problem is with the 14-50 connector being "legit" to use on a 40 amp circuit, does a NEMA 6-50 adapter allow the full 40 amps? The corded 14-50 adapter costs some $500 I believe. Picking up a NEMA 6-50 adapter for the other mobile connector is only $35. I found where the Mobile Connector is still only 32 amps with the 6-50 adapter even though the problem of being connected to a 40 amp circuit doesn't exist with that connector.

I find all the limitations to be difficult to track down. What's up with the HPWC only working at 48 amps while there is a chart which seems to indicate it has potential for supplying up to 80 amps. When can it supply 80 amps and to what? At one of my locations I'd like to have the maximum charging speed I can get. The rest are fine at 32 amps if that's all I can get from a 240 volt outlet.

Unless I can find a way to get more than 48 amps out of a HPWC, I think I'm going to use a 14-50 outlet with an HPWC which should let me get 40 amps charging my Tesla without unrolling the mobile connector and an outlet to charge other BEVs and power other devices without running multiple circuits. But I need two referrals to get the HPWC for free, lol!

Is your plan to put a 14-50 plug on the HPWC? You’ll want to set your HPWC current down to 40 if you do this.

 

[renambot]

The car can take 48A max at home. And you can use 80% of your breaker output.
Higher amperage lines allow for load balancing between multiple HPWCs.
Wall Connector

 

[gnuarm]

Is your plan to put a 14-50 plug on the HPWC? You’ll want to set your HPWC current down to 40 if you do this.

Yeah, I know. The cord has to be pretty short too I believe. But I don't have the HPWC yet. I'm planning on waiting for a couple of referrals to get a free one. They always charge better when they're free, right? By then I may just want it to run as fast as possible rather than having the flexibility. I just don't understand the issues of not running them faster than 48 amps. I could have sworn they ran at 72 amps when I've used destination chargers.

 

[redan]

I just don't understand the issues of not running them faster than 48 amps. I could have sworn they ran at 72 amps when I've used destination chargers.

They can only run as fast as the on-board charger permits. Current Long Range 3s (and standard S and X) max out at 48 amps. Mid and Short Range are/will be 32 amps. By putting the HPWC on a 100 amp line, you are future proofing your installation. Some MX and MS with dual chargers could max out at 80 amps (40 + 40) and some have upgraded chargers (48 + 24) to max out at 72 amps. My 2010 Roadster Sport has a 70 amp charger. When I installed my HPWC, I installed on a 100 amp line, just to have max capability in the future (my MS and M3 only charge at 48 amps, but I can charge the Roadster at the full 70 amps). I'm hoping the 2020 Roadster will have full 80 amp charging capability, especially with its oversized battery.

Onboard Charger

 

[renambot]

High-amperage 72A charger used to be an option. It might be now on model S/X with 100kWh batteries (100D cars).

 

[Webeevdrivers]

Yeah, I know. The cord has to be pretty short too I believe. But I don't have the HPWC yet. I'm planning on waiting for a couple of referrals to get a free one. They always charge better when they're free, right? By then I may just want it to run as fast as possible rather than having the flexibility. I just don't understand the issues of not running them faster than 48 amps. I could have sworn they ran at 72 amps when I've used destination chargers.

Well, if you put a 14-50 plug on it you’ll have to limit it to 40 amps because of the current limitations of the 14-50 plug. That and the 50 amp breaker in the box.

The onboard charger is limited to 48 amps.

Would appreciate if you keep me posted on what you decide and how it goes. I’ll be walking that path in about 8 months.

 

[xyeahtony]

Like it's been said above, it was redesigned because a lot of NEMA 14-50s are installed on 40amp outlets. In Canada, you can only draw 32A max anyways due to their electrical code.

Also i suspect because the base level model 3 was going to max out at 32A charging that they just wanted to streamline. Honestly, the charge rate between 32A and 40A isn't a big deal for me. I like the redesign of the new plugs.

 

[gnuarm]

Well, if you put a 14-50 plug on it you’ll have to limit it to 40 amps because of the current limitations of the 14-50 plug. That and the 50 amp breaker in the box.

The onboard charger is limited to 48 amps.

Would appreciate if you keep me posted on what you decide and how it goes. I’ll be walking that path in about 8 months.

Don't hold your breath waiting. I'm notoriously slow about doing things. I only have a Tesla because I wanted to drive to a wedding in Houston and knew there was a 2 month wait. I wanted to test drive a model 3 and that wasn't happening at that time.

But I will return to post what I end up with. I'd go ahead and put in the wiring for a HPWC on a 90 amp circuit (or maybe 100?) but I've got enough low gauge wire to run a 14-50 socket. So maybe I'll end up with both. Who knows. I'm sorry, which way is the wind blowing today???

 

[gnuarm]

Like it's been said above, it was redesigned because a lot of NEMA 14-50s are installed on 40amp outlets. In Canada, you can only draw 32A max anyways due to their electrical code.

Also i suspect because the base level model 3 was going to max out at 32A charging that they just wanted to streamline. Honestly, the charge rate between 32A and 40A isn't a big deal for me. I like the redesign of the new plugs.

Yes, I did some digging and found the info on the odd situation of NEMA allowing the use of 14-50 outlets on both 40 amps or 50 amps circuits.

The part I'm puzzled about now is that I'm 90% sure my car has charged at 72 amps from a destination charger which is just an HPWC, no? So why can't I get 72 amps at home? I know that is the default number in the limit adjustment in the car. I was testing a local J-1772 unit once and it started out charging at some current but with a 72 amp limit. After a while the limit adjusted down to about the charge rate.

I agree the difference between 32 and 40 amps is not huge, but 32 or 40 to 72 makes a large difference. That would let me get a full charge in just a handful of hours rather than waiting overnight. So I'd be able to arrive home, charge a while and get back on the road the same day if I needed that. This would have saved me driving 40 miles out of my way and waiting an hour to get a full charge on at the Supercharger 25 miles from one of my locations.

Next time I'm at a destination charger I will pay attention to whether it is running at 72 amps or a lower rate. I'm usually looking at the MPH and not entirely happy I'm not at a Supercharger.

 

[tga]

Huh? Is this because the "corded" mobile connector was designed before the gen-2 Mobile Connector?

Probably. It's based on the Gen 1 UMC. Also the plug is hardwired (no adapters), so one less connection point to worry about.

Since the problem is with the 14-50 connector being "legit" to use on a 40 amp circuit, does a NEMA 6-50 adapter allow the full 40 amps? The corded 14-50 adapter costs some $500 I believe. Picking up a NEMA 6-50 adapter for the other mobile connector is only $35. I found where the Mobile Connector is still only 32 amps with the 6-50 adapter

The Gen 2 UMC is limited to supplying no more than 32A, regardless of adapter/plug used - Mobile Connector

even though the problem of being connected to a 40 amp circuit doesn't exist with that connector.

Not necessarily true. There are plenty of 6-50's out there used for low-current welders wired with smaller wire/breakers.

I find all the limitations to be difficult to track down. What's up with the HPWC only working at 48 amps while there is a chart which seems to indicate it has potential for supplying up to 80 amps. When can it supply 80 amps and to what? At one of my locations I'd like to have the maximum charging speed I can get. The rest are fine at 32 amps if that's all I can get from a 240 volt outlet.

Unless I can find a way to get more than 48 amps out of a HPWC, I think I'm going to use a 14-50 outlet with an HPWC which should let me get 40 amps charging my Tesla without unrolling the mobile connector and an outlet to charge other BEVs and power other devices without running multiple circuits. But I need two referrals to get the HPWC for free, lol!

The max charge current available during a (non-supercharging) session is the lesser of (a) the max current offered by the UMC, HPWC, or J1772 EVSE and (b) the max current supported by the car's internal charger. If you install a HPWC on a 90 of 100A circuit and your car has a 72A charger, you can charge at up to 72A. If you have a 48A onboard charger, you can't go above 48A, regardless of the capacity of the HPWC.

The UMC determines the max current available by the adapter that is attached to it. The max current for the HPWC is set at installation by a dial switch. You set the switch to match the circuit it's installed on.

 

[Bogobec]

I’m currently charging at a supercharger and my current is limited to 32A. Can’t adjust this. Is this normal? Shouldn’t I be able to go up to 72A?

My X was produced on oct 2018.

 

[MorrisonHiker]

You are supercharging at 30 kW, not 32 amps. There's a huge difference. The 32 amp charge current shown at the bottom doesn't apply when you are Supercharging.

We don't know if you are at an urban Supercharger (72 kW) or a regular Supercharger which could allow you to charge at up to 120 kW. However, your battery is nearly fully charged. This will cause your battery to charge slower. You will only charge at maximum rates when the battery is far from being fully charged.

 

[xyeahtony]

I’m currently charging at a supercharger and my current is limited to 32A. Can’t adjust this. Is this normal? Shouldn’t I be able to go up to 72A?
View attachment 359795

My X was produced on oct 2018.

Supercharging rate is 30kw as stated above. That "charge current" you see is just a setting that is always on the charging screen, only applies to AC charging. (120/240V).

I mean just think logically for a second, do you think 32A charging would give you 147km/hr?