Charge Current dropped from 32A to 23. Should I be worried?

[M3Maybe]

Hi guys

I got my SR+ in July and have been charging exclusively at Superchargers (I live in an apartment).

Yesterday while I was charging at 150kW station, I noticed charge current dropped to 23. Didn't think much about it.

Today only drew 70kW from 250kW SC station and thought maybe something is wrong.

Researched little bit and it seems something is definitely amiss.

I already made and appointment for Mobile Service tech to come on Wed.

How bad is this problem?

Is my battery damaged?

Thanks!

 

[RandyS]

Sounds like you might be talking about two different scenarios. Current dropping from 32 to 23 is a Level 2 charging thing (at 240 volts or 208 volts), and usually means there is voltage drop from a poor connection, small wire, heating, etc.

The second statement about Supercharger power CAN be a normal thing, depending on what is going on with your car. At a low state of charge, charging power starts higher, and then it tapers off as the car is charged to prevent overheating the battery (a V3 "250 kW" charger will only stay high for a few minutes before tapering off; you won't get 250 kW for very long if even that much). If you starting charging at a SC site with a high state of charge on the car, then the charging power starts at a lower power level automatically....Maybe you could provide more information about what was happening? Thanks...

 

[M3Maybe]

Sounds like you might be talking about two different scenarios. Current dropping from 32 to 23 is a Level 2 charging thing (at 240 volts or 208 volts), and usually means there is voltage drop from a poor connection, small wire, heating, etc.

The second statement about Supercharger power CAN be a normal thing, depending on what is going on with your car. At a low state of charge, charging power starts higher, and then it tapers off as the car is charged to prevent overheating the battery (a V3 "250 kW" charger will only stay high for a few minutes before tapering off; you won't get 250 kW for very long if even that much). If you starting charging at a SC site with a high state of charge on the car, then the charging power starts at a lower power level automatically....Maybe you could provide more information about what was happening? Thanks...

Thanks Randy

I understand that as battery charge increases the amp decreases. But that is not what I am talking about.

Even after I finish charging, drive home and park, I see the Charge Current is still at 23A. It allows me to dial down from 23 but not back up to 32.

 

[RandyS]

What type of charging station at home are you using? Was it ever higher than 23 amps?

 

[M3Maybe]

What type of charging station at home are you using? Was it ever higher than 23 amps?

Not using any home chargers. Only superchargers.

It was 32A two days ago

 

[RandyS]

Sorry, I'm not understanding what you're saying.....You said "Even after I finish charging, drive home and park, I see the Charge Current is still at 23A. It allows me to dial down from 23 but not back up to 32."

You can't change any charge power or current settings at a supercharger site (that's DC Fast charging at levels higher than 23 or 32 amps). Only Level 2 charging really corresponds to 23 amps or 32 amps, which you say you're not doing. So I'm confused....Can you please elaborate a little more?

 

[GenralSpecific]

Take a picture of your screen. I bet you’re getting the offline charge current confused. The active charging current is probably not still showing and we can all help you better if we can get a picture of what you mean when you say you can adjust it while parked at home...

 

[camalaio]

Thanks Randy

I understand that as battery charge increases the amp decreases. But that is not what I am talking about.

Even after I finish charging, drive home and park, I see the Charge Current is still at 23A. It allows me to dial down from 23 but not back up to 32.

Ohhh, that was really confusing to me. So the number on the right side, on the bottom?

That is actually weird, but I'm not sure what to make of it. I can adjust it when parked and not plugged in, all the way to 48A (I have the LR, it goes higher). There have been partial power conversion system (PCS) failures before (one of three modules can die, resulting in a third of the charge current being dropped) but it's never been mentioned like this, and 23 is not 2/3 of 32 like I'd expect if that matched the other cases. That would be especially weird since your PCS isn't really doing much as you only Supercharge.

Let us know what comes of the service appointment, please. Very interested. Even if it's "something dumb" you did I'd be interested, because I cannot fathom what would cause this!

I doubt the 70kW from Supercharging is related to this at all though. I can make some real silly theories as to how they could be related, but I'll hold off. Nah, I can't resist. Battery is heated for Supercharging so it takes more power than normal - but if that's reduced even with a hot battery, I guess it could also impact the max AC charging speed. But I wouldn't think it would show up like that? And then it should impact regen. Have you noticed any significant regen limitations? (should show as dots on the left side of the bar underneath the speedometer)

Has it been colder at all recently?

 

[M3Maybe]

I went to get a pic but now the charge current is back up to 32A

I don't know what is going on

Since it is back to normal and I guess I will have to cancel the service appt

Thanks everyone

 

[bedoig]

Simplest answer...Dyslexia

 

[M3Maybe]

Simplest answer...Dyslexia

What a moron

Current charge reading IS dropping for few hours after I charge at 150kW stations. It goes up to 32 eventually.

 

[ucmndd]

What a moron

Current charge reading IS dropping for few hours after I charge at 150kW stations. It goes up to 32 eventually.

Jokes aside, you’re not listening.

The amps shown there has absolutely nothing to do with supercharging. Nothing.

It WILL however remember your setting based on geographic locations for L2 charging.

 

[Gasaraki]

Hi guys

I got my SR+ in July and have been charging exclusively at Superchargers (I live in an apartment).

Yesterday while I was charging at 150kW station, I noticed charge current dropped to 23. Didn't think much about it.

Today only drew 70kW from 250kW SC station and thought maybe something is wrong.

Researched little bit and it seems something is definitely amiss.

I already made and appointment for Mobile Service tech to come on Wed.

How bad is this problem?

Is my battery damaged?

Thanks!

Not enough information. What was the state of charge when you began charging those two times? How hot was it outside? Was there a car next to you?

The important thing is your state of charge.

 

[Gasaraki]

What a moron

Current charge reading IS dropping for few hours after I charge at 150kW stations. It goes up to 32 eventually.

That number that you can change in you screen HAS NOTHING TO DO WITH SUPERCHARGING. That is only for home charging. You can change that all you want. Doesn't do anything unless you are on a AC charger.

 

[Phlier]

@M3Maybe Hopefully, this will help you to understand a bit more about the different way the car charges...

When you charge at a supercharger, the car's onboard charger is completely bypassed; high voltage DC current flows directly into the battery. You cannot affect this charge rate by changing it on the page you're referring to. The supercharger itself determines this rate dynamically over the course of the charge session. The rate that you'll get is dependent on many things... if you are on a shared stall (if you're on stall 1A and there is also a car charging at 1B then you'll share the total charge rate), the temperature of your battery pack, the state of charge of your battery pack, and even the temperature of the supercharger's cable. Not getting the full rated charge of the supercharging station you're at is seldom cause for alarm.

When you charge at home, or using any AC power source, the car's onboard charger charges your battery by first changing the AC current into DC current. The rate at which this current flows is shown on the page that you're referring to. This particular page has nothing to do with supercharging.

Tesla has a couple of very informative tutorials on their site about how the car charges when charged from superchargers and AC power sources. It's worth taking a few minutes to check them out.

 

[Candleflame]

@M3Maybe Hopefully, this will help you to understand a bit more about the different way the car charges...

When you charge at a supercharger, the car's onboard charger is completely bypassed; high voltage DC current flows directly into the battery. You cannot affect this charge rate by changing it on the page you're referring to. The supercharger itself determines this rate dynamically over the course of the charge session. The rate that you'll get is dependent on many things... if you are on a shared stall (if you're on stall 1A and there is also a car charging at 1B then you'll share the total charge rate), the temperature of your battery pack, the state of charge of your battery pack, and even the temperature of the supercharger's cable. Not getting the full rated charge of the supercharging station you're at is seldom cause for alarm.

When you charge at home, or using any AC power source, the car's onboard charger charges your battery by first changing the AC current into DC current. The rate at which this current flows is shown on the page that you're referring to. This particular page has nothing to do with supercharging.

Tesla has a couple of very informative tutorials on their site about how the car charges when charged from superchargers and AC power sources. It's worth taking a few minutes to check them out.

that is not true, the supercharger does not determine the charge rate. Otherwise all our CCS and other third party stations would ruin our teslas haha.

 

[Phlier]

that is not true, the supercharger does not determine the charge rate. Otherwise all our CCS and other third party stations would ruin our teslas haha.

It's a joint discussion between the car and the supercharger, really, with both sides having a say in the matter.

 

[Candleflame]

It's a joint discussion between the car and the supercharger, really, with both sides having a say in the matter.

I hope the shitty 50kw tritium charger has NO say in the matter.

 

[Gasaraki]

that is not true, the supercharger does not determine the charge rate. Otherwise all our CCS and other third party stations would ruin our teslas haha.

The car and the charger has to be able to talk to each other first. If the car can't tell the charger "hey, I can take up to 250KW with this charger curve", then the charge doesn't happen. That's why third party chargers are such hit or miss. Anything wrong with either side will cause the charging to stop or not even start at all.

 

[Candleflame]

The car and the charger has to be able to talk to each other first. If the car can't tell the charger "hey, I can take up to 250KW with this charger curve", then the charge doesn't happen. That's why third party chargers are such hit or miss. Anything wrong with either side will cause the charging to stop or not even start at all.

that may be but the car always has the final say.