Wall Charger seems slow. Need Advice

[Gize]

Hello everyone,

New Tesla owner here. Did a search and didn't have luck with my particular question. I had a wall connector/charger installed and it's working, it says 48/48 A and 241V. I have only had the car a few days and have charged it twice but when it's still had high percentage of juice left.

I knew my car would slow down as it gets closer to full, but it's charging slower than I thought it would be. So my question is, is it normal for it to only be charging at 12 KW when I am at 59% SOC? Is this normal?

 

[vjason]

Should be charging about 1 mile per amp per hour up to ~mid 90% or so.

I charge at 40A which is ~10KW. Remember home charging uses an onboard charger, SC's bypass that and connect directly to the HV battery.

 

[qdeathstar]

48 amps x 240 volts = 11,520 watts.

 

[cwerdna]

^^^
Yep, that's the highest one can expect on a Model 3 at 240 volts.

Three Things Determine EV Charge Time may help the OP. Highest max amperage OBC of any vehicle that Tesla ships as new in the US is 48 amps now: Onboard Charger.

If you go back as far as Model S and all the way to current, Tesla in the US has offered this as OBC choices/as standard: 32, 40, 48, 72 and 80 amps.

The wall connector (it's not a charger) is the EVSE. And, AC charging uses the car's on-board charger.

 

[SSedan]

What was the temperature?
The battery needs to be warm to charge and it is a curve not a switch.
Also if you are in the car or have the door open HVAC can take a chunk out of charging efficiency.

The packs has to be I think above 32f to charge at all, and warmer than that to get all 48amps. The car and be taking 48amps but using a portion of that to warm the pack or cabin so the miles added looks low. You would be shocked how much power can be used in pack and cabin heating.

 

[Gize]

Should be charging about 1 mile per amp per hour up to ~mid 90% or so.

I charge at 40A which is ~10KW. Remember home charging uses an onboard charger, SC's bypass that and connect directly to the HV battery.

What was the temperature?
The battery needs to be warm to charge and it is a curve not a switch.
Also if you are in the car or have the door open HVAC can take a chunk out of charging efficiency.

The packs has to be I think above 32f to charge at all, and warmer than that to get all 48amps. The car and be taking 48amps but using a portion of that to warm the pack or cabin so the miles added looks low. You would be shocked how much power can be used in pack and cabin heating.

Thanks for the replies, I am still wondering if 12 kw at 59% is normal or not? Can you dumb it down for me please? SSedan ambient temp was about 60 degrees at the time and it was after a short 20 mile drive. My phone may be close enough it stays connected, will this keep the AC on and slowdown the charging speed?

Again thanks for taking the time for a noob and your knowledge!

 

[voip-ninja]

Thanks for the replies, I am still wondering if 12 kw at 59% is normal or not? Can you dumb it down for me please? SSedan ambient temp was about 60 degrees at the time and it was after a short 20 mile drive. My phone may be close enough it stays connected, will this keep the AC on and slowdown the charging speed?

Again thanks for taking the time for a noob and your knowledge!

Charge speed doesn’t really taper off for 240V charging until you get over 90%.
So whether charging from 10% battery or 80% battery the charge rate should be pretty consistent throughout the charge cycle.

Charging is only slowed if the battery is fairly cold.

with the charging amps you have you should be getting approximately 10% into the battery per hour of charging and this is completely normal.

 

[jjrandorin]

Thanks for the replies, I am still wondering if 12 kw at 59% is normal or not? Can you dumb it down for me please? SSedan ambient temp was about 60 degrees at the time and it was after a short 20 mile drive. My phone may be close enough it stays connected, will this keep the AC on and slowdown the charging speed?

Again thanks for taking the time for a noob and your knowledge!

You should see "42 MPH" as the charge rate. If you are charging at 42 miles an hour of charge, you are charging as fast as a model 3 long range / performance will charge on any NON supercharger connection.

@qdeathstar (who is an electrician) gave you the formula for 48 amps, so if you are charging at 11/12 kw you are charging at the max speed your car will charge unless it is connected to a supercharger.

 

[Adam3]

Thanks for the replies, I am still wondering if 12 kw at 59% is normal or not?

48A = 12KW. you can't charge any faster than that with your wall charger. Yes it's normal.

 

[Gize]

You should see "42 MPH" as the charge rate. If you are charging at 42 miles an hour of charge, you are charging as fast as a model 3 long range / performance will charge on any NON supercharger connection.

@qdeathstar (who is an electrician) gave you the formula for 48 amps, so if you are charging at 11/12 kw you are charging at the max speed your car will charge unless it is connected to a supercharger.

48A = 12KW. you can't charge any faster than that with your wall charger. Yes it's normal.

Thank you both, that's exactly what I was wondering. I also went out to the car and changed it to miles for just a sec and it said 36mph. it was at 86% now though. (Changed it back cause I don't want to obsess over miles all the time.)

 

[SSedan]

When you are in the car the HVAC runs siphoning off power.

On the temp thing some folks think it has to be cold to slow charging, well some of us don't live in Cali. This week I have had Regen disabled,this afternoon when I left Regen was barely available , and it was warm for here today.

When considering temp one should consider what the temp was, pack is heavy and does not quickly rise in temp as the morning warms though a 20mile drive and 50s should be warm enough. Probably just seeing HVAC siphon off a few KW so you miles added per hour looks low. Walk away and forget about it and it will be fine.

 

[cwerdna]

48 amps x 240 volts = 11,520 watts.

The above is correct. 11,520 watts = 11.52 kW. That's about the best you're going to be able to do at 240 volts with a 48 amp on-board charger.

To talk about 12 kW... well, that's rounding up by 480 watts...

Forget the "mph" stuff. It is not common for non-Tesla EVs/PHEVs to have anything about "miles per hour" for charging speed anywhere in their UI.

 

[ry-ballz]

Thanks for the replies, I am still wondering if 12 kw at 59% is normal or not? Can you dumb it down for me please? SSedan ambient temp was about 60 degrees at the time and it was after a short 20 mile drive. My phone may be close enough it stays connected, will this keep the AC on and slowdown the charging speed?

Again thanks for taking the time for a noob and your knowledge!

Amps x volts = watts

You have a 48 amp circuit at 240 volts. That's 11.5 kw

 

[Gize]

The above is correct. 11,520 watts = 11.52 kW. That's about the best you're going to be able to do at 240 volts with a 48 amp on-board charger.

To talk about 12 kW... well, that's rounding up by 480 watts...

Forget the "mph" stuff. It is not common for non-Tesla EVs/PHEVs to have anything about "miles per hour" for charging speed anywhere in their UI.

I understand, I had the wall connector installed 4 months before I actually got my car and was unfamiliar with what 12 kw really meant so switching to mph made more sense to me seeing how that was typically what I saw in the all youtube videos I watched to pass the time while I waited for Tesla Day. I just wanted to make sure both the car and wall connector were working as they should. Based on all the info everyone has so helpfully shared; I know I'm good. Love this community!