Am I being throttled?

[Dublin 'Eer]

I have a 2016 S 75 with around 21,000 miles on it. I've had the car for about 10 months, so I've obviously done quite a bit of longer trips and used Superchargers and CHAdeMOs. I have no idea of the percentage of DC charging and AC charging, but I'd guess it has been around 50/50 or relatively close to it.

Recently, my supercharging experience has been terrible. This has happened at many different Superchargers, and I'm normally the only car charging. I've never been on a paired Supercharger. When plugging in, I'll initially get a charge rate of 90+ KW sometimes up to 96-97. The charge rate will stay in the 90 KW range for about 10 added miles before the rate quickly drops tick by tick into the 40s or 50s KW range (and sometimes lower) over the next 10-20 miles added and then stabilizes in that range. If I unplug and move to another bay, the charge will start at over 90 KW and then quickly slow again, so it doesn't appear to be related to a hot battery or charge cable.

Today I deliberately ran the battery low before plugging in with only 24 miles remaining just to assure it wasn't related to the charge rate slowing as the battery filled, and this happened even with almost no juice in the battery. I plugged into all four circuits of an 8 bay Supercharger, and got the same results each time.

Obviously this is very frustrating and adds substantially to the time spent at Superchargers. Has anyone else experienced anything similar? I have not contacted the service center yet because I wanted to try once when the battery was nearly depleted to see if this happened. Since it did, it looks like I've either got an issue with the car or am being throttled.

 

[whttiger25]

Every single time you get sub-par charging speeds, call tech support to report it. Very often you'll be told there is a general issue with the supercharger. At the very least they will be made aware of the issue. If there isn't an issue with the supercharger you should ask them to schedule an appointment to have your car looked at.

Throttling due to high historical DC charging is reportedly not as severe as what you are describing, and resulted in a total 5-10 extra mins max for a nearly full charge from the several accounts I read when it was first reported as an issue. As an example, on a 90kwh battery, while you would previously have had a 115kw max, the new max is somewhere around 95kw. However, this was partially offset by a more gradual decline in power as the battery filled up, partially offsetting the negative affect of the lower max.

I haven't seen updates on this in a while but that's what was reported at the time.

 

[TexasEV]

Obviously this is very frustrating and adds substantially to the time spent at Superchargers. Has anyone else experienced anything similar? .

Yes, the dozens of people who have posted similar experiences in the existing threads on this problem.

 

[DarkMatter]

Are your louvers working okay? High initial charge rate that drops quickly can indicate a battery cooling problem on the car. Same if the condenser fan is not working for whatever reason.

 

[Dublin 'Eer]

TexasEV, although I didn't do an exhaustive search of all threads, I've seen many addressing slow supercharging rates but didn't see any where the charge started at a normal rate and dropped so dramatically almost instantly.

 

[Dublin 'Eer]

Are your louvers working okay? High initial charge rate that drops quickly can indicate a battery cooling problem on the car. Same if the condenser fan is not working for whatever reason.

I'll check those. Thanks for the advice.

 

[MarcusMaximus]

I have a 2016 S 75 with around 21,000 miles on it. I've had the car for about 10 months, so I've obviously done quite a bit of longer trips and used Superchargers and CHAdeMOs. I have no idea of the percentage of DC charging and AC charging, but I'd guess it has been around 50/50 or relatively close to it.

Recently, my supercharging experience has been terrible. This has happened at many different Superchargers, and I'm normally the only car charging. I've never been on a paired Supercharger. When plugging in, I'll initially get a charge rate of 90+ KW sometimes up to 96-97. The charge rate will stay in the 90 KW range for about 10 added miles before the rate quickly drops tick by tick into the 40s or 50s KW range (and sometimes lower) over the next 10-20 miles added and then stabilizes in that range. If I unplug and move to another bay, the charge will start at over 90 KW and then quickly slow again, so it doesn't appear to be related to a hot battery or charge cable.

Today I deliberately ran the battery low before plugging in with only 24 miles remaining just to assure it wasn't related to the charge rate slowing as the battery filled, and this happened even with almost no juice in the battery. I plugged into all four circuits of an 8 bay Supercharger, and got the same results each time.

Obviously this is very frustrating and adds substantially to the time spent at Superchargers. Has anyone else experienced anything similar? I have not contacted the service center yet because I wanted to try once when the battery was nearly depleted to see if this happened. Since it did, it looks like I've either got an issue with the car or am being throttled.

I've been having this exact issue quite a bit lately, and saw it at every single charger on my 400 mile trip on Saturday. I called support yesterday to report it and ask if they could look at the logs to see if anything stood out, but the guy said the temperatures in the logs all looked within spec and he couldn't see anything wrong on his end.

To give more information on the conditions: this was all at night with temperatures being ~80F. In each case, I saw the indicated outside air temperature on the dash shoot up to about 20-25F above the actual outside temperature while charging(it would then drop within a minute or two back to the actual outside temperature when driving away).

Also, I only thought to try this on the very last attempt, so it's only one data point but: When I saw the speeds drop the last time at Harris Ranch, I turned off "Range Mode" in the settings and it stabilized at 72kW instead of dropping down to ~58kW as it was before. I'm starting to wonder if Range Mode isn't just affecting the cabin cooling but also limiting power to the battery cooling while Supercharging

 

[MarcusMaximus]

TexasEV, although I didn't do an exhaustive search of all threads, I've seen many addressing slow supercharging rates but didn't see any where the charge started at a normal rate and dropped so dramatically almost instantly.

Agree with this. The other threads have to do with consistent slightly lower charging speeds(e.g. 85kW max instead of 95-96). I haven't seen any other threads about this specific issue(normal maximum charging speed followed by a massive, fast plummet to 40-60kW when still at low battery percentage)

 

[DarkMatter]

charging slow at Superchargers

Many parts of this thread talk about exactly this. Check out the graphs on the first post. Look familiar? There's also discussion of the cooling problems later on. If it's happening everywhere instead of just at a few Supercharger locations, it's probably the car inlet connector or a cooling problem.

 

[Mrwatchdawg]

So my loaner that I have right now has the same issue.

Starts at 95 and than drops down to about 50.

 

[Deanoy]

Took delivery 09/12/17. Model x 75d. Have supercharger only 3 times with capacity down to 60-70 miles. Starts off great at 95kw and by the time I reach about 125 miles in charge it drops to the 40-50kw range and only continues down from there. Sounds like what others are experiencing. I see the posts in this thread go back to aug 7. Has anyone found out anything new about this problem?

 

[DarkMatter]

Same location every time? How hot is the handle? That taper does seem a bit hard compared to normal, but my sense of that isn't really well calibrated for the 75s.

 

[Deanoy]

Charged once in Allentown, Pa, once in Harrisburg,Pa and once in Buffalo, Ny. Not sure about the handle each time. Will be supercharging later today in Erwin,Ny and will pay attention to handle heat.

 

[BlueRocket]

Charged once in Allentown, Pa, once in Harrisburg,Pa and once in Buffalo, Ny. Not sure about the handle each time. Will be supercharging later today in Erwin,Ny and will pay attention to handle heat.

Just a note... Allentown has always charged super fast for me and maintained fast charging rates up to at least 70% charge

 

[Dublin 'Eer]

I started the thread back in August, and since it has come back to life, I thought I’d post an update. Short answer is no, this is not throttling. Longer answer – see below.


I subsequently had the service center pull my logs which resulted in an answer that everything was normal. During trips involving other superchargers, I’ve had normal charging experiences where the charge rate maintains a 94-96 KW level until the taper curve kicks in.


Now that it is cooler in Ohio, I was curious if the superchargers that had been giving me issues during the summer would charge normally. During a recent visit to one on a cooler day (temperature in the 60s), I experienced the same issues I’d been having in the summer with the charge starting in the mid-90s and quickly dropping to the 50-60 range. As I was charging, another Tesla with a 75 battery arrived, so I walked over to talk to the driver. We watched his charge rate, and he was experiencing the exact same issue. We tried multiple chargers with the same results each time.


After leaving, I called the Tesla support number listed on the Superchargers. They were aware of issues at that supercharger and implied it was some sort of hardware issue.


At the end of all of this, we know this isn’t throttling issue, many people are experiencing the problem, it does not appear to be heat related, and Tesla is aware of the issue. Probably the best course of action is for all of us to call and report the problem each time it happens. I’m sure Tesla is aware of the superchargers with issues, but if we keep reporting them, maybe whatever repairs need to be made will happen more quickly which needs to happen because charge times are dramatically increased when encountering one of these faulty superchargers. What I'm not sure of is if this is only an issue with 75 batteries.

 

[appleguru]

Took delivery 09/12/17. Model x 75d. Have supercharger only 3 times with capacity down to 60-70 miles. Starts off great at 95kw and by the time I reach about 125 miles in charge it drops to the 40-50kw range and only continues down from there. Sounds like what others are experiencing. I see the posts in this thread go back to aug 7. Has anyone found out anything new about this problem?

This sounds like a normal 75 taper, no problems.. the 75 packs are 350V and charge slower than the 85/90/100 packs.