22kw upgrade concern appearing on porsche car configurator.

[daveo4EV]

(Electrical layperson alert) Also, it’s not clear to me if UK/Irish residential electrical conventions for a single phase circuit supporting 22kW are somehow different to how a US 4-conductor 100A circuit would be set up.

US EV chargers (EVSE's ) are 3 conductors:

1 conductor for 120V
1 conductor for 120V
1 conductor for electrical ground

AC charging in the US is dominated by the J-1772 plug-type - which has 5 conductors

2 conductors for high-voltage AC power
2 conductors for low-voltage pilot/communications "pin"
1 conductor for electrical ground

the J-1772 connector is used for 120V & 240 volt charging (L1 & L2 respectively) - in the case of L1 charging the two "high voltage" conductors become one 120V leg and an electrical neutral…

the North American/US plug standard offer 4 conductor and 3 conductor "plug types" - but in the case of the 4 conductor plug types they are for compatibility only - and the 4th conductor is unused by the EVSE…

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[BigBob]

The answer i got was:
It seems there is a component that may overheat/fail if charging on single phase above 6kw with the 22kw 'upgrade' fitted. They are working on a fix which may be software or hardware. I guess there is a risk a software fix might be throttling the car to only accept 6kw. Hope not.

If it does fail the car won't work/will need to be recovered. Will be covered on warranty.

 

[whitex]

The answer i got was:
It seems there is a component that may overheat/fail if charging on single phase above 6kw with the 22kw 'upgrade' fitted. They are working on a fix which may be software or hardware. I guess there is a risk a software fix might be throttling the car to only accept 6kw. Hope not.

If it does fail the car won't work/will need to be recovered. Will be covered on warranty.

And that answer I suspect is what the whole "Porsche whistleblower" media bs-storm started with - a grain of truth. Yea, not exactly Porsche's proudest moment, but shit happens. Limiting the charge rate could open Porsche to some lawsuits, I know Tesla lost and was ordered to pay compensation ($16K per owner IIRC) for limiting charging rates and battery capacity on older cars in order to limit possible damage to the batteries.

 

[batteredhaddock]

Those of you in Ireland and the UK (where this new language has appeared in the configurator), may I suggest also reaching out to the manufacturers of your respective EVSE’s to enquire if they are aware of Taycan onboard 22kW charger failures in the wild under single phase level 2 charging at the full 22kW? The Porsche PMCC and PWCC units are manufactured by E-Systems MTG. In the UK, I believe Anderson’s beautiful EVSEs have been the Porsche UK recommended home install. While they might immediately redirect you to Porsche, they might also share their awareness of a known issue.

I contacted Andersen after the issue was first brought to light on here so they are aware of it now. For my older, discontinued PM1 stand up unit, they can limit it to 24A. Still enough for my home charging requirements to be honest (Taycan charges so fast and I’m not in the sticks so can get to a number of rapids, including Porsche 1 mile away). Shame on the Andersen side is that when I first got mine (and they were just getting going) you could still access the Konnect web site and select the charge rate from there. I did ask if they had any plans to add that functionality to the app and they said no, but that was before they were aware of this recommendation to use 25A max on single phase.

I’m still going with my intention to use the 22kW unit and will get Andersen to set me to 24A (and as per Tigerbalm use 32A public single phase when essential). Perhaps the mentioned fix may be in place by the time my car arrives (hopefully end of March/April) but for now I’ll assume 24A and be happy if that improves.

 

[BigBob]

I contacted Andersen after the issue was first brought to light on here so they are aware of it now. For my older, discontinued PM1 stand up unit, they can limit it to 24A. Still enough for my home charging requirements to be honest (Taycan charges so fast and I’m not in the sticks so can get to a number of rapids, including Porsche 1 mile away). Shame on the Andersen side is that when I first got mine (and they were just getting going) you could still access the Konnect web site and select the charge rate from there. I did ask if they had any plans to add that functionality to the app and they said no, but that was before they were aware of this recommendation to use 25A max on single phase.

I’m still going with my intention to use the 22kW unit and will get Andersen to set me to 24A (and as per Tigerbalm use 32A public single phase when essential). Perhaps the mentioned fix may be in place by the time my car arrives (hopefully end of March/April) but for now I’ll assume 24A and be happy if that improves.

Wallbox has a dial on the app that lets you select the charge rate. So I got lucky on choosing that charger i guess (choice made on size of unit). Hopefully won't be an issue when my car arrives, also by March, with a bit of luck.

 

[BigBob]

As I have the 22kw on board charger, i'm being a good boy and have dialled my EVSE back to 25 amp - Which I was under the impression (from the configurator) would equate to 6kwh charging speed. However, looking at the MyPorsche app, it's giving me only 5.1 to 5.4kw.

Do you think it would be potentially harmful if i increased the amperage on the evse until I hit the 6kwh in the car that the configurator 'recommends'?

I realise there is little clarity from Porsche on what the actual problem is with the 22kw unit when charging single phase.

Thoughts?

 

[RAHRCR]

As I have the 22kw on board charger, i'm being a good boy and have dialled my EVSE back to 25 amp - Which I was under the impression (from the configurator) would equate to 6kwh charging speed. However, looking at the MyPorsche app, it's giving me only 5.1 to 5.4kw.

Do you think it would be potentially harmful if i increased the amperage on the evse until I hit the 6kwh in the car that the configurator 'recommends'?

I realise there is little clarity from Porsche on what the actual problem is with the 22kw unit when charging single phase.

Thoughts?

Charging is a pull not a push. The car will pull the 22KW if it is available…not more than that.

 

[whitex]

Charging is a pull not a push. The car will pull the 22KW if it is available…not more than that.

Yes, except that the EVSE continously (many times per second) informs the car which is "pulling" how much power (current actually) can be pulled, and that number is user adjustable on some EVSEs.

 

[BigBob]

Charging is a pull not a push. The car will pull the 22KW if it is available…not more than that.

Thanks. The maximum a single phase charger (in the uk) will provide is 7.4kw. That's what most people will have in their homes here. But porsche put a warning up that you should throttle that back to 26amp/6kw if you had the optional 22kw charger installed as it could somehow damage it.

So really trying to work out if i can tweak the throttling on the evse above the recommended 25amp, as the 25amp/6kw limit porsche has recommended is actually equating to 25amp providing only around 5.1-5.4 kwh (not 6kw) according to the porsche app.

** As whitex mentions, I'm able to adjust the power on my domestic evse - maximum of 32amp, but i've throttled it back to 25amp.

This is the comment on the configurator:
To increase the lifetime of the 22kW on-board charger, when charging from a single-phase power supply, it is recommended to limit maximum power to 25A (6kW).

 

[Jhenson29]

Do you think it would be potentially harmful if i increased the amperage on the evse until I hit the 6kwh in the car that the configurator 'recommends'?

I wouldn’t. I find it unlikely that they meant the rate at the battery.

 

[W1NGE]

Thanks. The maximum a single phase charger (in the uk) will provide is 7.4kw. That's what most people will have in their homes here. But porsche put a warning up that you should throttle that back to 26amp/6kw if you had the optional 22kw charger installed as it could somehow damage it.

So really trying to work out if i can tweak the throttling on the evse above the recommended 25amp, as the 25amp/6kw limit porsche has recommended is actually equating to 25amp providing only around 5.1-5.4 kwh (not 6kw) according to the porsche app.

** As whitex mentions, I'm able to adjust the power on my domestic evse - maximum of 32amp, but i've throttled it back to 25amp.

This is the comment on the configurator:
To increase the lifetime of the 22kW on-board charger, when charging from a single-phase power supply, it is recommended to limit maximum power to 25A (6kW).

I think it would be fine to adjust the ampage to get as close to 6kW as you can.

That said how much charging time do you lose if you leave at 5.4kW (25A) - if not material then why not leave as is?

 

[BigBob]

I think it would be fine to adjust the ampage to get as close to 6kW as you can.

That said how much charging time do you lose if you leave at 5.4kW (25A) - if not material then why not leave as is?

Well i suppose it keeps getting further and further away from the hoped for 7.4kw I'd be getting at 32a - especially when it seemed to be mostly getting around 5.1 (not 5.4) kw.
And last night for example, as I had let the battery run quite low it was going to take longer than i wanted to get to target charge this morning (by well over an hour than i would have achieved at 6kw let alone 7.4kw).

I do know the voltage into my house is at the very low end of the minimum requirement of the electricity supplier - around 220v, So i guess that is probably the reason for the low kw number at 25a.

I know if i get stuck for time i can just turn the dial up to 32a on the evse, but i was wondering if anyone more electrically minded than me (not hard) had a view on whether increased power (kw) or current (amps) is the most likely cause of stress to a component like the 22kw unit.

 

[Jhenson29]

I know if i get stuck for time i can just turn the dial up to 32a on the evse, but i was wondering if anyone more electrically minded than me (not hard) had a view on whether increased power (kw) or current (amps) is the most likely cause of stress to a component like the 22kw unit.

I don’t know the details for the reason of the reduction; but I would almost certainly expect it to be current.

Heat results from current. (and by the square of current at that).

For most components, a reduction in voltage does not mean you can increase current to achieve the same power. Voltage and current ratings are typically independent because they have different requirements.

 

[W1NGE]

Yep - expert input needed but isn't power= amps * volts? Therefore in your case if voltage is already maxed out the best you can do to increase power is to increase the amps to get nearer to the recommended power oitput?

I'd bump up the amps (warranty in my back pocket).

 

[BigBob]

Yep - expert input needed but isn't power= amps * volts? Therefore in your case if voltage is already maxed out the best you can do to increase power is to increase the amps to get nearer to the recommended power oitput?

I'd bump up the amps (warranty in my back pocket).

Yeh. I think the issue is that the suggested limit is assuming 25amp always equates to 6kw. Which per your equation isn’t the case. So really a question of which one is the problem.
still mute point I guess as I was assured Porsche were working on a fix when I specced it. And as that was about 6 months ago, I’m sure it will be released any minute now! ?

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