Low kW at Supercharger, but full Amps

[badiban]

Hi everyone, I was at the Fort Worth Supercharger (urban charger maxing at 72kW) the other day, and for some reason, I was only getting around 30-40kW max. My notes about the car and conditions:

• The amperage was at a full 32A (I have an SR+)
• The car was getting about 40kW at the beginning, and decreased to around 33kW towards the end of the session
  
• I was charging from 65% to 80%
• Battery had enough time to precondition so that it didn't have any dots for regen
• I changed the GPS destination from my original destination to the Supercharger about 10 miles outside the Supercharger
• No error messages
• Weather was about 70F, but the night before was colder
• I tried 3 different chargers at this station, all 3 were giving me about the same rate of charge

I am just wondering if this is normal, or if it may be something wrong with my car.

Thanks!

 

[jjrandorin]

going to guess its this:

I was charging from 65% to 80%

I would guess that, if you look at one of the various charging curves around, you would find the taper at that state of charge is built into the car, so to answer your question, there is nothing wrong with your car.

 

[badiban]

going to guess its this:



I would guess that, if you look at one of the various charging curves around, you would find the taper at that state of charge is built into the car, so to answer your question, there is nothing wrong with your car.

Thanks! I didn't think the taper would be so aggressive if it was at the 72kW chargers, but I guess it's across the board...

 

[jjrandorin]

I dont have an SR+ so havent paid that much attention to supercharging for one, but when I googled a SR+ charging curve and picked the first website that came back for me:

(Here's How Tesla Model 3 LR and SR+ Charging Power Differs)

Glancing at the chart, it looks like there is a fairly aggressive taper starting around 60% or so

 

[1100MCM]

• The amperage was at a full 32A (I have an SR+)

• I could be wrong but I don’t think amperage is displayed anywhere on the car display while supercharging. I think the 32 you see is just the default level 2 charge amps.

 

[JulienW]

As tiij664 stated the amperage in settings is for the onboard AC charger at 220V. Superchargers (which is a DC charger) bypasses the onboard AC charger.

An Urban SC at a full power would be about 200A (70kW=200Ax350V).
So at 40kW you were getting about 115A.
A Level 3 250kW can go up to about 700A.

 

[badiban]

• I could be wrong but I don’t think amperage is displayed anywhere on the car display while supercharging. I think the 32 you see is just the default level 2 charge amps.

Yup, you and @JulienW are correct. I learned this in my research for this.

 

[Gasaraki]

Yeah, it's because the high state of charge and the temperature. I have charged from 50 - 80% a lot so i know the rate of charge usually. I get slightly higher than that ~65KW at 70%+ to 45KW or so at around 80-85%.

 

[cdswm3]

I dont have an SR+ so havent paid that much attention to supercharging for one, but when I googled a SR+ charging curve and picked the first website that came back for me:

(Here's How Tesla Model 3 LR and SR+ Charging Power Differs)

Glancing at the chart, it looks like there is a fairly aggressive taper starting around 60% or so

That's an old Charging curve. SR's can now charge at 170KW at the start.