Got kicked off a SuperCharger...

Got kicked off a SuperCharger...

I arrived at the SuperCharger in Metz, France. It is a 2-stall portable SC.
I was the first to arrive, docked and started charging at 117 kW. All fine. I entered a local supermarket to buy some roadwarrior-food.

Within 10 minutes of leaving the car, i got an alert on my iPhone that charging was interrupted. So i walk back to the car but it was charging. Glancing at the phone i noticed a second notification telling me that charging resumed quite soon after it was interrupted.

However, it was now charging at 24kW and not 100ish as it did a minute earlier.

Then i noticed the reason. A second Tesla had arrived and started charging. I got kicked out somehow when he started charging and as i was now "number two to arrive" from the SC's perspective, i got the lower priority. When the other MS started to get "fuller", my charging speed increased accordingly.

I use SC's a lot (i drive a lot) and had other MS'ses enter the second, paired Stall many times and never got kicked off from "mine" because the second, paired stall started charging. Until now. How rude...
The result was that because i was charging much much slower, i had to wait about 40 minutes longer overall (i needed a 100% range-charge to get to the next SC).

To explain the priority thing: two Stalls form one SuperCharger. An 8-Stall SC are actually four SC's and not eight. An SC has 12 "sections" capable of delivering 10kW each which are divided over both paired Stalls when both are in use. If only one Stall of the pair is in use and the cars battery has a very low State Of Charge (SOC), it will allocate all 12 sections delivering 120kW. If a second car starts using the other paired stall, sections are "taken away" from the first stall/car and allocated to the second stall. This of course reduces the charging speed of the first car. Example: The first stall, 12 sections in use, might get reduced to 9 as 3 are decoupled and allocated to the other stall.
As soon as the first car is lowering it's charging "speed" because the battery is getting "filled" more, sections are decoupled and added to the second car's stall, increasing it's charging "speed" more and more.
That's how SC's work and that is why you see MS drivers pull into Stalls of which the paired stall is not in use whenever they get the chance. Stall-pairs are easy to spot as they are called 1A and 1B, 2A and 2B etc. etc where the "1x are the two that are paired. | January 5, 2015

I forget, can you interrupt a charging session by pressing the button on the handle, even if the car is locked?

johncrab | January 5, 2015

France continues to be an enigma to me. They export electricity and run trains electrically. Alstom is a world innovator in generation and distribution, yet in some parts of the country it is possible to turn on a lamp and have three blocks go dark. Delivery infrastructure in some places seems to go back to Edison.

Your information on actual charging is good to have. I'd love to get into the design of the battery and charging systems but what you say corresponds to my hypotheses of how this is handled.

Captain_Zap | January 5, 2015

@ O

I believe you are correct. I wasn't going to put it in print though. But, since you broke the ice...

Bighorn | January 5, 2015

Not sure how you got disconnected/interrupted with the plug locked to the charge port.

DonS | January 5, 2015

I am curious why you lost first priority. In my experience, the second car gets 30kW minimum, and then more as the first car reduces charging current.

cpmarino | January 5, 2015

Theoretically speaking, in such a case would it actually be better for the 2nd user to wait until the 1st user is finished and then be able to charge at the higher rate all on his own? Certainly if the 1st user is close to full that should be the case. But in a case where two Teslas fully depleted arrive at the exact same time, sounds like it might take less time to charge each fully individually than for both to be "sharing" the same charger for what sounds like a much longer period of time. Am I nuts?

ElectricSteve | January 5, 2015

@ omar: no

@ BigHorn: i'm in the dark as you are but it happened. The car was locked (i was about 400 yards away) and charging fine. Then poof, interrupted and auto-resumed within a minute.

@ johncrab: if i look at the "power-lines on a puny wooden pole" feeding an entire neighborhood in many regions in the US and Canada, i'd say a bird with a bad hairday can blackout that whole community. I once saw an F150 slide and take out such a wooden pole north of Toronto, Canada. Sparks flying and kapoof, village had juice no more. Who is calling the kettle black? ;-)

ElectricSteve | January 5, 2015

@ DonS

I lost first prio because i got interrupted and "returned as the second one to arrive".

ElectricSteve | January 5, 2015

@ cpmarino

I need about 70 minutes to go from "11km left in the battery" to completely full. If i would be first, get all and the second car get's nothing because he started a couple of seconds after me, that would totally defeat the idea of having two stalls. Not to mention deliver a very negative experience.
The idea of having 12 sections and dividing them as they do, is smart from an investment's point of view. The massively reduced costs versus the chance that two very empty Tesla's arrive at the same pair like that is so remote that it makes perfect sense to me.
Sure, it can be kinda "uncool" for the number two car if's he/she is unlucky but how often does the most negative of scenario's actually happen...

DonS | January 5, 2015

Your are right, but I think of the reasoning a bit differently.

Total maximum power of the Supercharger is the limit, so charging two cars at once with 60kW, or charging one car then the other at 120kW is the same total time.

It is the end part of the charging where the time is wasted because two cars near the end of charge at 30kW would not be using the full capability of the Supercharger.

If Tesla were to redesign the Supercharger with four charging cables, along with a doubled total power, then the sharing among the four would be more likely to use more of the total capacity more of the time.

ElectricSteve | January 5, 2015

I guess i was wrong when i said No to Omars question. I started googling and indeed, pressing the button on the SC handle while charging will indeed interrupt the charge (and will auto resume if the connector is not pulled out within X time).

That must mean that the owner of the second MS pressed "my button" to give himself priority ?!?

Captain_Zap | January 5, 2015


Bighorn | January 5, 2015

135kW chargers give 120 to a single, but 135 to the pair, so the math is a little more complicated.

TeslaLandShark | January 5, 2015

Wow, this button pushing thing is not a good thing to hear...

ElectricSteve | January 5, 2015

Nope. It would mean the birth of "SuperCharger Hooliganism"...

EESROCK | January 5, 2015

I don't think it matters who started charging first at a shared charger. However, the battery that's more empty will charge at a faster rate.

ElectricSteve | January 5, 2015

It does matter Eesrock. It really works as i described.

suresv | January 5, 2015

Yeah this button pushing thing is definitely not a good thing.. Is this confirmed? Meaning some one can interrupt a charging session even without the FOB by simply pressing the button?

@ElectricSteve - May be you could have tried the same on the other Tesla - that way you and the other owner could have done a "Last Man Standing" show!

ElectricSteve | January 5, 2015

@ suresv

I think my wife would have killed me long before i had a chance to win.

But honestly, the more i google, the more i'm starting to get convinced that this is what must have happened. There is no way that the owner of that gray, german MS "pressed my button" by accident. He knows this "trick" and abused the absence of me and my wife to make his charging go faster.

If you read this, german owner of that grey MS in Metz on December 27th 2014, i, the owner of the red, Swiss S85, wish you many happy tows due to drivetrain failures. How low can you go...

Ampfreak | January 5, 2015

Exactly the same happened to me also at the Metz Supercharger in France. I was first charging with full power, then went to the shopping center nearby for lunch. When i came back, a second black Tesla was there and my charge was reduced to about 25kW. I stopped and resumed charging which of course did not help. I could imagine that the second Tesla was somebody charging there regularly and using the interrupt trick.

ElectricSteve | January 5, 2015

I charge in Metz often and had other cars starting charging after me before, but i never had an interruption. I find it unlikely that the single two-stall mobile SC there has a technical issue causing those interrupts.

I sincerely hope this is not the start of a new trend in EV hooliganism besides ICE'ing where EV owners start messing about, screwing other EV owners. I thought we were a decent bunch...

randrave | January 5, 2015

That's really low. You can't run around touching another man's buttons!

KWTESLA | January 5, 2015

Electric Steve

Rate of charge is not always some thing that can be blamed on the other guy. If your car is nearly fully charged the rate slows down significantly. I met a guy at Tejon Supercharger who had 250 miles of range and was complaining about how slow his car was now charging. He thought it should charge at 300 amps all the time.....

ElectricSteve | January 5, 2015

Kwtesla, did you even bother to read my post completely ?!?

tes-s | January 5, 2015

It could have been a temporary blip with the supercharger. The same thing happened to me about a year ago - and I was sitting in my car. It has not recurred, but I rarely have to "share".

Another car pulled up and plugged in. My charging went down to 90kW as expected. About 5 minutes later I stopped charging for no reason - I think the message was "Charging Interrupted". This was before app notifications.

I unplugged, and plugged back in - and was a bit annoyed as I realized I was now #2 and charging at 30kW.

I'll have to test the button thing at a supercharger sometime.

mrspaghetti | January 5, 2015

I agree that it could have just been a glitch, but it is certainly suspicious. I will keep that in mind if ever I find myself at a supercharger where the stations are half filled or more.

This evil tactic could possibly be solved with a software update. E.g., if the button is pushed but the charging probe is not unplugged then you remain #1 when charging resumes.

Sam_S | January 5, 2015

If the button is pressed, how long is the colitis interruptus?

GabrielB | January 5, 2015

Who will be the first to market a wrap-around lockable interrupt button cover? Similar to a Lock-Out-Tag-Out (LOTO) Electrical work safety cover.
It could also be a thin (hard) cover that slides over the connector from the contact end, and is held-locked in place as the connector is locked into the charger port.

This connector chastity device will prevent unwelcomed button play.

GabrielB | January 5, 2015

I think you meant; coulombic interruptus :)

LOTR99 | January 5, 2015

If it happened to me, and I had to wait around an extra 40 min at the SC, I would have called Tesla Ownership and asked them why it happened and perhaps even had them pull the logs and see exactly why it happened.

Rheumboy | January 5, 2015

I think pushing the button is like stealing the squeegee from the other pump....never mind

Mark K | January 5, 2015

This button back-door is not helpful for promoting civility.

The good news is that Tesla has the power to enforce a particular priority entirely through firmware.

They can "denounce" any button press while the plug stays connected.

It can work however they want it to, without changing the hardware at the SuperChargers.

This is not a complicated update.

david.baird | January 6, 2015

If find this... disturbing...

I can only imagined that the interruptions were intentional by the other owner as we've never heard of these interruptions happening before.

It's rather despicable and indeed I had always thought we Tesla owners were morally superior to all other human beings.

garygid | January 6, 2015

Normally, if someone presses the "unlatch" (also "open flap") button on
the SC plug while charging is in progress, that means "I want to interrupt
(stop) the charging so that I can safely pull out the charging plug (without
high currents in the power leads)."

If this is done without the car unlocked, the charging plug will not unlatch,
so it cannot be removed from the vehicle, and charging resumes (or starts
all over again, apparently) when the "unlatch" button is released.

So, it might be better for the car to NOT stop charging if the car is locked,
and then "stealing your priority" would no longer work, as long as your
car was locked. Presumably, just a software "fix" (or security upgrade).

However, pressing the "unlatch" button might still be used to "see if the Tesla
is charging", because the flashing green light was turned off, and there is no
other way (that I know of) to determine if the Tesla is actually charging.

Further, there appears to be no way to tell how much power the attached
vehicle is using, or an estimate of how long it will be charging before
it is done. The vehicle just appears "dormant", even "dead".

So, it might be better to continue to show the big charging status bar
on the dash display whenever the car is actually charging, which
could include the estimated time remaining in large print, easy for
an outsider to see.

And, perhaps better to keep blinking the green light ring as well?

duidui | January 6, 2015

Could the signal from the cable's button also got to your car's receiver when the new car try to open his own charge port ? If so, it maybe an unintended interrupt.

garygid | January 6, 2015

Another cable can open your car's charging flap from 10 or 20 feet away.
So, the "other" RF signal can activate your car's "flap-open" RF receiver.

Thus, the real question is "Does your car use its RF flap-open receiver to
detect the quit-charging button press?"

lolachampcar | January 6, 2015

No, the quit charging is a physical change in resistance on the pilot line caused by pressing the button on the charger handle.

At least three possibilities here-
The SC "glitches" when #2 is plugged in allowing #2 to appear as the first plugged in.
#2 presses your button to see if you are still charging or to pop their charge door because #2 handle button is not emitting RF. This would be the glass half full explanation for someone pressing your button (or, in this case, buttons).
Lastly, #2 wants priority.

When it comes to people, I'm often quick to assume half full. I am also wrong on many occasions.

The question for me would be - Was it the same #2 on the two separate occasions where priority switched? It is unlikely that more than one person has learned and is using this trick up till now. Of course, now that we are all discussing it, it is reasonable to assume we will start to see a lot more of it.

EVSE Pilot Signal

garygid | January 6, 2015

In the J1772 domain, the "release" button causes a resistance change
on the Proximity line, not the Pilot signal line.
Presumably that is the same for the Tesla charge port, since it also
works with an J1772 EVSE plug (using Tesla's 5-pin "straight-through"

In the J1772 domain, the car is supposed to quit drawing charging
current within a small fraction of a second after the "unlatch" button
is pressed, to avoid high current arcing on the power pins if the
charging plug is somewhat (too) quickly pulled out of the car.

lolachampcar | January 6, 2015

oops... my mistake

Brian H | January 6, 2015

That station, with only 2 stalls, is the most vulnerable kind, because there is no alternative "pair" to go to to find a full power outlet.

WSE51 | January 6, 2015

While it is certainly possible that the other Tesla owner pushed your button, it is also possible that the charging interrupted on its own. This has happened to me twice -- once at Nephi Utah when I was alone at a Supercharger, and another time at Harris Ranch where there were other cars charging but no one else on my circuit. At Nephi it resumed charing automatically but at Harris Ranch I had to reboot my screen before it resumed.

txakoli | January 6, 2015

Pushing the button while still locked to the vehicle will interrupt the charge. It will then begin charging again.

It happened to me at my brother's house on Christmas Day. I received app notifications of "charge interruption" and "charge started'.

Red Sage ca us | January 6, 2015

It could be that at the temporary, trucked in, forklift 'sled' locations for Superchargers, one side is always the 'slave' to the other, and that is where you plugged in... Thus, you were the XO until the actual CO took the conn... Make it so, Number One. Engage!

tes-s | January 6, 2015

I tried it - if you press the button when the car is locked while supercharging, it interrupts the charging and then resumes.

wizkid057 | January 6, 2015

No doubt that the other person pressed the button on your charge cable after plugging in in an effort to get more power quickly. Another owner and I were curious about this at the Glen Allen, VA charger and it works as expected and switches priorities.

The charger must by design disable current when the button is pressed. It has no knowledge of if the car is locked or not. This is part of the EVSE/Supercharger.

Since we know the car sends it's VIN to the supercharger cabinet when authenticating, it should be simple for Tesla to fix this in the supercharger software by just remembering the VIN of the last car on that charger. If it is the same and it has been an insignificant amount of time since interuption, just use the timestamp for when it actually started started charging originally for priority. This way the other owner would have to continue to hold your charger's button down in order to get more power, which I would hope would be a lot less common than someone just quickly tapping the button.

I hope Tesla does implement this.

Brian H | January 6, 2015

I generally discount demands the SC take on more management duties, but this sounds like a very fair and worthwhile one.

Pungoteague_Dave | January 6, 2015

I experienced a "charging interrupted" message on my iPhone today while charging at Mitchell, SD in 3 degree weather. I walked a block back to the car and saw the charge port cycling though light blue, white, dark blue and green. The dash indicated "charge port open" and charging interrupted at various times during the cycle. I re-seated the plug, but it kept happening. I moved the car two stalls over (no one else there) and it initiated and completed charging just fine.

On the current road trip we have had a wide range of Supercharger speeds and idiosyncrasies. We've done 31 Supercharges so far at 29 chargers. Most of the time we are alone at Superchargers, and several times a stall change has worked to increase speed to over 300 mile per hour. We know we should call into customer service when there are problems at superchargers, and have done so twice, but it is such a PITA - Tesla needs to implement remote monitoring of the Superchargers, or do regular site inspections.

It is interesting to note that almost all of the Superchargers on our current route have had signs with "30 minute general parking" allowed - not EV restricted.

ElectricSteve | January 7, 2015

@ P_Dave

We have those 30 minutes max. signs over here in Europe as well. Pointless from a technical perspective but maybe it has a legal reason. Dunno and can't find any authoritive (useful) info about it either.

Brian H | January 7, 2015

As P_D has mentioned, many parking lots have a minimum # of slots that must be public.

marenavrn | January 9, 2015

After reading this thread I tried an experiment in my own garage. Model S85, plugged in and charging. Went in the house and came back out into the garage without a fob. I was able to push the button on the charge cable, light turned orange and after a few seconds went back to green to charging.