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Either way, we weren't stuck for a charger, just disappointed that in my 5 years of driving EV's I've never seen a rapid charger only putting out 25KW. And yes I know if I'd waited longer than 10 minutes it would have started to increase.
I did a test before travelling to London recently. The nearest SuC was 24 miles away and I started with a cold battery but despite pre-heating I only saw 24kw on the couple of stalls available. Not shared. So I gave up and came back. During the actual trip at Reading (16 stall) I saw ~60kw and only on the way back did I see the 100kw max (at the time) on the way back at the Membury West service station.

Now I have Scan My Tesla installed via the OBDII adaptor I will be able to relate temps better to charge speed. What I have noticed is that in normal driving the pack stays around 20-21 C in cold weather so way off the 50 C targeted for maximum supercharging. It can take quite a long time to reach higher temps as I assume Tesla don't want to shock the cells with rapid temperature changes. There's normally a 1 C difference between "coolant" temp and pack temp which goes up to 4 C with pre-heating. Only reference I can give you is that the regen pips are gone by 22 C.

Also having just watched the latest Out of Spec Motoring vid on YT there's a lot of variability in charging speeds from several factors. Plus not all stalls at a site will necessarily be at the stated max in the info so try the highest numbered pair first I just in case they were the latest pair installed.
 

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Now I have Scan My Tesla installed via the OBDII adaptor I will be able to relate temps better to charge speed. What I have noticed is that in normal driving the pack stays around 20-21 C in cold weather so way off the 50 C targeted for maximum supercharging. It can take quite a long time to reach higher temps as I assume Tesla don't want to shock the cells with rapid temperature changes. There's normally a 1 C difference between "coolant" temp and pack temp which goes up to 4 C with pre-heating. Only reference I can give you is that the regen pips are gone by 22 C.
I think people under-estimate how long a cold battery stays cold, this can take ~70mi or more, drive like a maniac though to shorten this :)

Plus not all stalls at a site will necessarily be at the stated max in the info so try the highest numbered pair first I just in case they were the latest pair installed.
Disagree, they all go to the same cabinets with the same feed, focus on empty pairs.
 

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traversing across europe I regularly saw 30kW being the second car on paired stalls but this ramped up to 100kw within 30 seconds of them leaving. The bigger frustration was not knowing if someone had just arrived or was about to leave - the chargers need some sort of traffic light system so when you approach you know which is the most efficient charger to join. On at least 2 occasions joined a paired station at 30kw only to see a later arrival join a different station and their pair left before mine.
 

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The bigger frustration was not knowing if someone had just arrived or was about to leave - the chargers need some sort of traffic light system so when you approach you know which is the most efficient charger to join
Unfortunately, because charging is non-linear, and dog-slow on the top end "about to leave" becomes a human element more so than technical.

Of course the larger the site the better all around (queuing, chances of shared stalls, etc.) and we will always need more of those :)
 

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I just plugged into 4b with 4a occupied at Scotch corner and charge rate limited to 50kW. The person on 4a left and my charge rate jumped to 100kW but within minutes a MX pulled into 4a and as soon as he plugged in my charge rate dropped to 50kW again. I was surprised by this as I thought the first car charging on a pair got the full rate.
Just then the person on 1b left so I moved the car to 1b and the charge rate jumped back to 100kW.

Strange to see Johny Carpervert get in the MX next to me!
 

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This may be a US phenomena currently but may happen here as they install more posts.
As far as we are aware, this has not happened at any UK site. Oxford might just be debatable until we know more after recent changes there. @arg commentary from the cab or feed level re. feeds for other pairs?

I just plugged into 4b with 4a occupied at Scotch corner and charge rate limited to 50kW. The person on 4a left and my charge rate jumped to 100kW but within minutes a MX pulled into 4a and as soon as he plugged in my charge rate dropped to 50kW again. I was surprised by this as I thought the first car charging on a pair got the full rate.
Just then the person on 1b left so I moved the car to 1b and the charge rate jumped back to 100kW.

Strange to see Johny Carpervert get in the MX next to me!
Strange and not seen this, but I wonder if this would still have happened if you stopped charging, plugged in and charged again at the same stall when no-one else was charging (and before 2nd car reduced yours) - by background - there was some rumour (and since been fixed, not that I would have tried this) a long time ago that you would get a higher charge if you went to the partner stall and pressed the button on the other-charging-car, which would make your car the longest-running session, thus higher charge-rate.

Either way, my understanding was that a shared stall should affect you no more than 30kW, but this was before the recent ~150kW bump so maybe that's 50kW now?
 
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