[North American] - Home / Residential charging update (using Tesla Universal Wall Charger)

[whitex]

11 kW on baord charger is AC

DC charging is upto 270 kW - and my Macan has done 275 kW once…

this has nothing to do with the DC charger.

@krissrock , another way to explain it is this. Your car battery can only charge from a DC charger. Your car comes with a built-in DC charger (a.k.a. onboard charger) which is powered by AC from the outside of the car (from the EVSE, a.k.a. wall connector). This onboard charger is typically maxing out at between 6KW and 19.2KW. However, you battery can also charge up to 270KW from an external (not onboard) DC charger, which is what all the fast DC charging station are - they are just a much bigger version of what your onboard charger is. As a matter of fact, the original Tesla Superchargers were literally made out of 12 onboard chargers in a single supercharger enclosure (each onboard charger was 9.6KW, so times 12, the Supercharger had a max charge rate of 115.2KW).

 

[whitex]

So that means you have 2 EVSE’s on one 240 volt line with a 100A breaker? I’m just wondering because we have 1 Tesla charger and I need to plan for when I get the Macan. I’m not sure whether to add another circuit which is expensive, use an adapter (which will only allow to charge one vehicle at a time plus plugging/unplugging each vehicle), or use a splitter like the NeoCharge.

Yes, 3 EVSE's actually. Read @daveo4EV extensive post above for details. Your best path forward will depend on which EVSE you already have.

 

[whitex]

So you're saying that if my EVSE is set to 40 amps, and the car tries to draw more, the EVSE will let it?

Yes, up to the circuit breaker capacity (which will trip if exceeded).

Or even worse, if I have a 16 amp EVSE and hook it to my Macan, and there is some communication error, the EVSE would let the car draw more?

No, communication error should cause the EVSE to cut the power to the car completely.

That does not seem like a safe design to me.

EVSE is essentially a glorified extension cord with GFCI protection, ability to detect when the car is connected and therefore only turn power on when all pins are connected, and ability to tell the car in real time what is the the maximum current consumption can be. There is a additional capability to advertise ventilation capabilities of the site, but that does not apply to your Macan. All those capabilities are specified in the SAE J1772 standard.

 

[dgkhn]

this is very very helpful!!! 11 kW mentioned in the manual - wow - Porsche really screwed up this one!

Now that I read this more carefully (and note the comments about charging overhead below the chart): 95 KWh/11.5 hours = 8.3 kw net charging rate. 95 kWh/10 hours=9.5 kw net charging rate. I wonder if the rate being reported by the car is the gross power pull or the net charging rate. I'm getting a reported 9.1 - 9.3 kw on my 44 amp EVSE. What are folks seeing on their 40 amp EVSEs: same, or less? What about on 48 amp set ups? And keeping in mind, 240v x 48 amps is 11.5 kW, not 11; or another way of looking at this is 11 kW/240 v is 45.8 amps, not 48. A lot of potential for ambiguity here.

 

[daveo4EV]

I see 9.3/9.4/9.5 kW reported by the vehicle on my 48 amp EVSE
I see 9.3/9.4/9.5 kW reported by the vehicle on my Porsche 40 amp EVSE (PMCC)

the 48 amp EVSE has the same charge rate as the 40 amp EVSE…in both cases it's seems to be reporting the "raw" power being provided to the vehicle.

 

[whitex]

I'm getting a reported 9.1 - 9.3 kw on my 44 amp EVSE.

What EVSE model are you using and what is the circuit/breaker size to which it is connected to? The reason I am asking is because 44A is a very atypical number for a North American EVSE. I'm 99% sure you cannot even signal 44A limit using J1772 protocol, so the EVSE would have to talk ISO15118 (PLug-And-Charge which Macan would have) or Tesla proprietary protocol (only applicable to Teslas), both of which allow much finer grain current limits.

That said, one thing to note: for AC,
Power[KW] = Voltage[V] * Current [A] * Power Factor
Power Factor should be close to 1 for EV charging, so if the car is reporting pre-losses number, and the car is in fact pulling 44A, that would mean your voltage is 207-211V AC, which is low unless the EVSE is on a 3-phase power (typically found in business rather than residential locales). This could mean you have poor power regulation from your electricity provider, but it could also mean you have a problem with your wiring which is causing a larger than expected voltage drop when the car is pulling 44A. If that is the case, some part of your wiring (wherever the voltage is dropping) will start heating up, which could be dangerous.

 

[whitex]

I see 9.3/9.4/9.5 kW reported by the vehicle on my 48 amp EVSE
I see 9.3/9.4/9.5 kW reported by the vehicle on my Porsche 40 amp EVSE (PMCC)

the 48 amp EVSE has the same charge rate as the 40 amp EVSE…in both cases it's seems to be reporting the "raw" power being provided to the vehicle.

It looks like the car is reporting raw. The variation between 9.3-9.5 is from your house supply voltage variation.

Sounds like the car is limiting itself to 40A (or 40.7A). Have you tried using a lower power EVSE (e.g. 32A) and see what the car shows. Note that using PMCC, the charger is probably not u sing J1772 signaling, especially if it can show you current SoC on the PMCC, so the Macan may behave differently on PMCC vs. regular J1772 EVSE.

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