Some California Superchargers not providing maximum charging rates

[wdolson]

I suspect there are quite a few different reasons for slow downs. Heat will degrade electronics as well as wiring and superchargers do run a lot of current through those cables. There may also be something going on with utilities that the tech didn't know about.

He did find something wrong in the wiring of the supercharger that initially gave me such slow charging rates at Mantecca and he said there was one stall at Gilroy that had some serious problems the day before. We determined that I may have been at the stall he ended up repairing later the same day.

I think the SpCs that are charging in the 60Kw up to 120Kw range may sometimes be something upstream from the supercharger itself, or it may not. Today I charged at the Grants Pass, OR and Springfield, OR superchargers. I got around 60Kw at Grants Pass, but that was OK because I was getting some breakfast. By the time I was done, the car was charged up enough to get to Springfield with a decent reserve and I got pretty much full power at Springfield.

 

[cpa]

A little late in reporting in, but my rates when I drove to Portland and back were pretty much crappy. This was September 24/25 going up and September 29/30 coming home

Manteca (15% SOC) started out at 116, dropped down to 60-something then rose to 78 until 40%, then slowly dropped to 48 where it stayed until around 70%.

Corning was similar to Manteca.

Mt. Shasta was early AM, so hard to tell with the cold battery what the rate would have been.

Bend started out at 118, then dropped down to the dread 78, then ramped up to 90 or so at 26%.

Sandy was OK.

Seaside (21%) started out great, but then dropped down to 60-something for a while before rising to the dread 78.

Lincoln City was cold in the morning, so never got above 80.

Crescent City was OK.

Eureka was cool in the early morning, and the rate was limited to around 80.

Ukiah was like bad--forget the actual numbers.

Manteca was the same as when I was there the week earlier.

I have made the trip from home to Mt. Shasta City five times before my trip two weeks ago. I can state that with the reduced power at the SC, my most recent trip was about 45-50 minutes longer than in the past.

I checked Fresno before going home just to get a taste, and Fresno was bad too, starting out at 116 and then dropping to 60-something before climbing to 78 with a small rise to 80-something awaiting the normal taper.

 

[MikeC]

Odd that some only experience this behavior very infrequently. My car has yet to supercharge normally this summer at any location. Makes me wonder whether there is a fault with my car that is compounded by bad connectors at superchargers.

Had the same issues on the 5 in a brand new Model X, so it's not your car.

 

[FlatSix911]

My guess is the manufacturing tolerances in the cable/connector in the car isn't good enough and/or wear and tear on the car and cable connectors. If the charging cable and car charging port don't mate correctly, there will be heat build up and then presumably safety related throttling.

Tesla is probably at the bleeding edge here. Pushing 300A through a connector that gets a huge amount of insertions probably isn't done much anywhere else. I don't think it is purely a co-incidence that the throttles settle around 50-60 kW which is the maximum power that Chademo systems routinely use worldwide. My point being that it is possible that Tesla has mis-engineered their cable/car connector and now they are stuck with it. This would also explain why they haven't spoken about the issue.

Nonsense.

Superchargers will throttle based on dirty or otherwise poor connections. Temperature at almost all points of the charging chain is monitored (at least according to the supercharger tech I spoke with) and will result in ramping down if temp or anything else is out of line. The pins Tesla uses aren't huge, and have to be constantly monitored to ensure they are safe. It seems like Tesla made the choice to achieve safety via close monitoring in software, vs safety in oversized, over-spec'd, physically larger connectors. Chargepoint engineer I spoke with also agreed with this. He thought they used super close monitoring of the connectors as a way to safely put so much current through a smaller connector, and that was a smart way to accomplish high speed charging.

More nonsense and FUD.

I was lucky enough to meet a Tesla tech at the Menteca SpC yesterday. Interestingly, Tesla is transferring him to the NW soon and he just got back from house hunting in the county where I live. He was replacing the plugs on a couple of the SpCs, but was also asking people about their charge rates. I was only getting about 50Kw initially and he had me move to the other SpC on that pair and I got 120Kw. He took apart the one that was only delivering 50Kw and found a wire that was loose.
On the others being slow he said the California SpCs get some of the heaviest use in the world and many times they don't get a chance to cool down after use. If the unit gets too hot it goes into limiting to save itself. He also said that after a lot of charging cycles the hardware gets degraded from the constant heating up. The good news is they are designed to still work as they degrade, but the bad news is a lot of California SpCs get a lot of abuse and the hot summers don't help. It's a lot tougher for an SpC stall to cool down in 100F heat than it is in 70F temps.

A Tesla tech speaks the truth ...

 

[trils0n]

More nonsense and FUD.

Never been accused of FUD before. Could you explain why you think my statement was FUD? Or why you think a Supercharger tech would relay FUD about the safety elements of the Superchargers? I was complimenting Tesla on their ability to safely put large amounts of current through their connector.

The car/Supercharger will certainly reduce current based on poor connections/increased resistance. I have had this happen multiple times. It is a good safety measure. Similar to how AC charging will lower the current if voltage sag is detected.

Not sure why you would criticize me for claiming that superchargers will throttle if temperature is out of line, and then praise another poster for stating the exact same thing -- that superchargers will go into reduced power mode when they overheat.

 

[Lump]

Buana Park & Santa Ana should be opening soon, if 60KW is reported then we know Tesla is capping.

 

[wdolson]

Buana Park & Santa Ana should be opening soon, if 60KW is reported then we know Tesla is capping.

Or something is throttling the superchargers. I think it's been suggested in this thread that the utility may be the one doing the throttling.

 

[Lump]

Or something is throttling the superchargers. I think it's been suggested in this thread that the utility may be the one doing the throttling.

I would accept the utility excuse if capping was occurring at Harris Ranch & a few other sites but its been reported across the country starting last June so I place responsibility on TM.

 

[jeffro01]

Since we're all full of WAGs currently, which Tesla could help with immensely if they'd at least acknowledge the issue and provide some context, I think it's a combination thermal management and use. The statement the Tesla tech made really backs this up. The hardware isn't cooled well enough in the cabinet and as such as time goes on, degrades slightly after each time it really heats up. Given the use of the hardware in some locations, this matches up...

Again... Just a WAG...

Jeff

 

[Khatsalano]

Those are brand new. Warm day?

Nope, 70F. Following day, capped at 60 kW at Manteca ... not hot and SOC was at like 20%. Kinda ridiculous.

- K

 

[wdolson]

Nope, 70F. Following day, capped at 60 kW at Manteca ... not hot and SOC was at like 20%. Kinda ridiculous.

- K

But you don't know how much usage that stall had gotten that day, nor do you know how many heating and cooling cycles it's been through. When I was there the tech was working on 1A and 1B. He had just finished 1A when I arrived, but it had problems and he found something he missed. He switched me to 1B when he was finished with it and it ran at 120Kw.

 

[apacheguy]

But you don't know how much usage that stall had gotten that day, nor do you know how many heating and cooling cycles it's been through. When I was there the tech was working on 1A and 1B. He had just finished 1A when I arrived, but it had problems and he found something he missed. He switched me to 1B when he was finished with it and it ran at 120Kw.

You know, last summer (2015) I SpC at 120 kW on several days with temps > 100 F. I'm not buying this thermal argument.

 

[aesculus]

I think it's been suggested in this thread that the utility may be the one doing the throttling.

I can pretty much assure you they are not. First off the superchargers are not really heavy loads to the utilities. Second they don't have that level of visibility or control.

 

[ecarfan]

I can pretty much assure you they are not. First off the superchargers are not really heavy loads to the utilities. Second they don't have that level of visibility or control.

Agreed. Every time someone posts about the local utility possibly limiting power to a Supercharger site, I wonder how the utility could remotely monitor how much power a site was drawing and then remotely control and reduce that power draw. I am not aware that an electric utility has installed (at least in the US) the equipment needed to do that.

I am not a power grid expert so of course I could be wrong...

 

[4SUPER9]

This Thanksgiving, I am supposed to make a loop from LA to Phoenix, to Las Vegas and back to LA. I am a bit nervous. The last time I did this identical trip was 2 years ago. I ran into only 2 other Teslas in the whole trip, until I got to Barstow, which was newly expanded and no wait. This is a lot of driving, and I am now thinking of taking the ICE. One tank of gas will get us all the way to Phoenix without stopping. That will save us an hour of charging, but much more if charging speeds are reduced. I am especially worried about the return traffic on Thanksgiving. Now that there are so many vehicles, I can see myself waiting in a line, only to get a slow charge, potentially adding 2 hours to a 4.5 hour trip.

 

[Lump]

We cheered when 90KW was increased to 120KW & expected 135KW & possibly 150KW.

Now that 60KW is reported at most SpC's that I would need for family vacations I am glad I didn't trade in my ICE for a second Tesla.

1.Tapering at 80% SOC is something we understand but sucks having to explain to kids.
2. Waiting in line for a charge in California...UGH.
3. Locals overstaying at SpC while Tesla takes no action is unacceptable.
4. Finally getting a stall & pairing with someone who started charing 2 minutes before you is always a fun suprise.
5. Tesla capping without explanation, is this another overhyped feature where they have discovered a problem or costs too much so they have decided implement capping? Battery swap being reintroduced soon?

SpC experience has worsened.

 

[NOLA_Mike]

You know, last summer (2015) I SpC at 120 kW on several days with temps > 100 F. I'm not buying this thermal argument.

I, too, never had an issue before THIS summer (and this is my third summer of supercharging). I'm buying the thermal argument - maybe the fans in the charger cabinets aren't functioning properly (whereas they were before) or maybe there are filters at the air intakes that are dirty so the fans can't move as much air as they used too. Or, maybe Tesla changed the coding in the charger firmware which doesn't allow them to get as hot as once allowed before they start reducing power.

Even this year, I have experienced this malfunction at many different superchargers across the country but I usually don't experience the premature taper in the early morning or at night (when the superchargers are less used and the temperature is less).

I wish Tesla would own up to the issue and tell us what's going on so we could quit guessing.

 

[jeffro01]

I wish Tesla would own up to the issue and tell us what's going on so we could quit guessing.

^^^This... 100% this...

Jeff

 

[joebob73]

Was at Burbank Supercharger this morning around 9:30am. There were one or two free stalls and the temperature was about 73 degrees. 50kW charge rate at 1B. When my paired partner left 1A, I unplugged and replugged and it was still 50kW. SOC was about 50%. Based on temp and the early time of day (plus some availability of extra stalls), I don't see this as an overheating issue.

 

[apacheguy]

Good point. I've seen those fans roar in the heat. They can easily keep up with the thermal load when less than 80 F. That would have to be some severe dust collection to restrict the air flow sufficiently to cause problems. Also, doesnt Tesla maintain the sites exactly for reasons such as these? I could understand if there were a couple that fell behind in the maintenance routine, but not all chargers
along the 5 and the 101.