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Charging on 32A 1P 230VAC EVSE - Only Getting 16A

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Hello All...

I have a couple of Q's, the first relating to charging from a UK domestic EVSE at 32A...

A friend has a Model S with an 85kWh pack. My S has a 60kWh pack.
Friend has a 32A Rolec EVSE which will only charge his S at 16A. It will charge mine at 32A.

Has anyone else had this issue?

Next, has anyone heard of a 'slave charger'?

I ask as when my friend contacted Tesla regarding his problem and explained that my S worked fine with the Rolec and his didn't, Tesla asked friend for my VIN and VRM which he gave. Tesla later responded to him that when my S had gone in to W Drayton to have a 'black gloop on the outside of the drivers door window when wound fully down in hot weather' issue resolved, they also fitted a 'slave charger'. This was news to me (and nothing on the 'Repair Order' emailed to me after the repairs were done)!

Can anyone shed any light on this?
 
1) Check dashboard to make sure the car is set to use more current (you can dial it down, or it will do so automatically if it detects too much drop on the line or line noise)
2) They probably meant the second charger option, which takes the older cars from 40A charging to 80A charging. In newer cars they start at 48A and can be software unlocked to 72A.
 
Right...the two chargers are set up as a master/slave configuration, but getting the second charger is normally a couple thousand dollars. You say they just put one in without you ordering it or asking for it and didn't include it on the invoice? That seems incredible.
 
1) Check dashboard to make sure the car is set to use more current (you can dial it down, or it will do so automatically if it detects too much drop on the line or line noise)
2) They probably meant the second charger option, which takes the older cars from 40A charging to 80A charging. In newer cars they start at 48A and can be software unlocked to 72A.
Except for Europe the chargers are set up to handle 3-phase since their plug and a lot of public charging supports it. So one charger is 230v*3phases*16a = 11kW, similar to the 240*40a = 9.6kW of North American chargers. However, that means if you connect to a single phase charge point, you only get 16a*230v = 3.7kW. So you need two chargers to take full advantage of the 32A socket described above. In fact, there are 64a 3 phase charge points available that can deliver 43kW. Which is really cool since the infrastructure for one of those is a fraction of what's needed for DC charging.

Except that it's not supported by Tesla or most other cars.
 
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I was under the impression that UK Model S had one of two solutions applied to mitigate this 16A charging limit on single phase and single on-board chargers. First, they built a bunch of Model S cars with dual chargers and software limited them to 11kW whether single phase or three phase. Those cars could be upgraded over the air to full 22kW three phase charging ability upon payment for the upgrade to dual-chargers. More recently, I thought they were building the cars with a new junction box that could distribute the single phase power to all three phases of the on-board charger, the same way that the Mobile Connector and single phase Wall Connector do externally. Now with the 48A/72A chargers introduced with the X and facelifted S, the junction box is integrated with the charger, so this should be a non-issue.

It appears that your friend has neither of these remedies applied to his car. He should discuss the issue with Tesla. After all, they were the ones that were recommending the Rolec on the home charging point subsidy scheme.
 
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Reactions: davewill
Latest update: Friend has had a visit from his local Tesla service manager whose S (15 plate, I gather) charges correctly at 32A off the Rolec. He has gone off saying Tesla will examine friend's car's logs and see what that reveals but the issue is clearly with friends car... Stayed tuned!