PMCC Capacity?

[atebit]

I was poking around the Suncoast site looking for Taycan stuff, and happened across their product page for the PMCC. This caught my eye:

Max Power: 9.6 kW - 19.2 kW (future)

So I guess that means that the PMCC is capable of delivering up to 19.2 kW, even though (the current) Taycan will only ever request 11 KW max?

I guess I had hoped that it was the EVSE that was limited to 11 kW, and that maybe after Porsche got some experience with how the battery handles charge rates, that the on-board charger could be (literally) amped up to request more current from the EVSE via an update.

Sponsored

 

[daveo4EV]

North American market PMCC is limited to 9.6 kW if you're plugging it in to a plug socket (like a NEMA 14-50 or 6-50) - anything more than 9.6 kW (40 amps) requires all EV chargers to be hardwired.

future PMCC's may be rated for 19.2 kW - but that would a require a hardwired connector from Porsche (not yet listed, priced, or shipping).

the labeling on the back of my PMCC clearly indicates the unit is a 9.6 kW unit- so I"m not sure it can do 19.2 kW even with the correct hard-wired supply cable.

future PMCC's may be rated up to 19.2 kW and will adjust based on the type of supply cable you currently have attached - this would be nice - but this is speculation at this time as I have yet to see Porsche's actual North American product offering in this space.

porsche clearly has 19.2 kW capable products since PMCC units shipping in other regions support up to 22 kW charging rate - so it's clear this can be done, but the exact offerings for North American market have yet to be priced or documented.

_IF_ the unit is a 19.2 kW it would be less portable as it would need to be hardwired into a 100 amp circuit and because it would be hardwired it would no longer be portable - now you could "detach" the supply cable (quite easily it's designed to do so) but then you'd have a "live" supply cable left behind hardwired into a 100 amp junction box - unless Porsche makes the supply cable "smart" in some manner to cut off and de-energize the cable…

If the unit is configured for 19.2 kW it's not portable
if the unit is configured to be portable it's maximum charge rate is a 50 amp circuit (via NEMA 14-50 or 6-50 plugs - 40 amp charge rate is 9.6 kW)
It's unclear if there are actual internal differences between the current 9.6 kW units and any future 19.2 kW units - they may all be 19.2 kW capable, but since there is no supply cable to "unlock" the extra capacity porsche has cable the North American units as 9.6 kW.

The Taycan standard onboard charger supports 11 kW charging (this 48 amps charge rate at 240 volts, which requires a 60 amp breaker) - 11 kW charging requires by electrical building code a hardwired connection - currently Porsche offers no guidance on any North American PMCC configuration that would support 11 kW charging - although if they can support 19.2 kW, they could support 11 kW - but so far nothing has been documented or priced or shipped. 11 kW would require a hardwired supply cable just like 19.2 kw - since _ANY_ 240V electrical appliance more than 50 amps must be hardwires and can not be plug based.

I'm sure Porsche can do all this - but they haven't yet seems to work out all the details.

And even when they do it will be grossly overpriced and there will be more affordable higher quality options on the market. You can purchase several excellent 60/48 amp 11 kW EVSE for less than 1/2 the Porsche unit today - and ClipperCreek makes an excellent high quality bullet proof very reliable 100/80 amp 19.2 kW EVSE that will support the Taycan and any other EV.

you do not need to "wait" for Porsche in this space - and their offering is overpriced and unfortunately not a leading choice in the EVSE market - unlike their vehicles, which are also overpriced, but really quite excellent.

 

[daveo4EV]

I guess I had hoped that it was the EVSE that was limited to 11 kW, and that maybe after Porsche got some experience with how the battery handles charge rates, that the on-board charger could be (literally) amped up to request more current from the EVSE via an update.

all indications are there are two physically different on board in-vehicle chargers that can be installed in the factory.

the Porsche "standard" on board charger can handle 240 volts @ 48 amps for an 11 kW maximum AC charge rate
the optional upgraded Porsche on board charger can handle 240 volts @ 80 amps for a 19.2 kW maximum charge rate (22 kW for the rest of the world, but US is limited to 19.2 kW since that is the maximum documented standard for J-1772 North American EV charging hardware)

In the US Porsche ships Taycan's with 11 kW support, but strangely only specifies 9.6 kW since the porsche charger provide with the vehicle only supports 9.6 kW - the maximum rate an pluggable EVSE can support- the car actually supports 11 kW but you need a non-Porsche EV charger to take advantage of that.

the 19.2 kW charger option is most likely the exact same 22 kW hardware shipped tot he rest of the world, but in North America there are _NO_ EV AC L2 240V chargers that will ever offer more than 19.2 kW - since that is all J-1772 can handle/document

it is very unlikely (but unconfirmed) existing 11 kW limited Taycan's can be "software" upgraded beyond 11 kW support - but Porsche has hinted there maybe a hardware upgrade package offered at some future date to retrofit some Model year Taycan's by dealer service - this offering is undocumented and unpriced at this time.

19.2 kW charging is possible in North America and does exist today -but it's a rare "find" in the wild and not at all common - It requires a 100 amp AC 240 V breaker - and most residential/small businesses have only 100/200 amps for their entire building electrical service - dedicating an entire 100 amp AC 240 volt circuit for an EV charger is an expensive upgrade rarely supported by any increase in business revenue, and is impossible in many many residential circumstances since 100 amp service is for the ENTIRE home and therefore infeasible to have an additional 100 amp circuit just for charging your EV.

It's nice when you find it but I wouldn't count on encountering a lot of 19.2 kW chargers while roaming the US or Canada - most of the public chargers you'll find (90% or more) are 40 amp or less (sometimes much much less).

 

[daveo4EV]

it helps to confuse the situation in that there are two electrical limits at play when charging an EV…

1. there is the maximum rate of charge the external charging equipment can offer - this is the PMCC, ClipperCreek, ChargePoint, JuiceBox, etc…this is the EVSE
2. there is the maximum rate of charge the vehicle can accept - this is the AC/DC converter installed by the manufacturer at the factory

when charing any EV you can only charge at the maximum rate supported by BOTH the vehicle and the EVSE…

Example the standard Cayenne hybrid only supports a maximum charge rate of 3.6 kW.

If you plug a Cayenne/Panamera hybrid into a PMCC that supports 19.2 kW - the Cayenne will only charge at a rate of 3.6 kW - since that is the maximum amount of power the AC/DC converter installed in the factory in Germany can support - now the PMCC WILL charger the Cayenne but only at it's reduced capacity of 3.6 kW.​

if you plug a 19.2 kW capable Taycan into the ChargePoint chargers at Valley Fair Mall in San Jose, CA - your 19.2 kW Taycan will only charge at the 6 kW rate offered by the ChargePoint chargers - if charged at a higher rate the circuit breakers on the Chargepoint chargers would trip and cut off the power to protect the wiring and circuitry of the Chargepoint chargers.​

to charge at a rate of 19.2 kW - you need to have both an EVSE (ClipperCreek+ 100 amp breaker) _AND_ a 19.2 kW capable vehicle…if you don't have both then you will charge at some lower charge rate than is ideally possible.

if you plug a standard Taycan into a 19.2 kW PMCC or Clippercreek - it will only charge at an 11 kW rate since that is the maximum rate supported by the hardware installed at the Porsche factory.

the charge rate your vehicle will charge at is _NEGOTIATED_ every time it's plugged into a J-1772 charger - it's part of the J-1772 electrical/communication standard and is well documented and adopted by all EV manufacturers who sell EV's in North America.

the external EVSE "tells" the car how much power it can offer. And the car then only request power up to the limit offered by the charging hardware it's plugged into.

So the charge rate is the combination of your charging hardware in your garage & what your vehicle is capable of accepting.

Some example maximum charge rates by vehicle are:

1. Tesla Model S - 40 amps - 9.6 kW
2. Tesla Model S - 80 amps - 19.2 kW - optional charger upgrade
3. TEsla Model 3 standard range - 32 amps - 7.2 kW
4. Tesla Model 3 long range/performance - 48 amps - 11 kW
5. Chevy Bolt - 32 amps 7.2 kW
6. Nissan Leaf - 16 amps - 3.6 kW
7. Nissan Leaf - 32 amps - 7.2 kW - optional charger upgrade
8. Cayenne Hybrid - 16 amps - 3.6 kW
9. Cayenne Hybrid - 32 amps - 7.2 kW - optional charger upgrade
10. Taycan - 48 amps - 11 kW
11. Taycan - 80 amps - 19.2 kW - optional charger upgrade
12. Tesla Model S - 48 amps - 11 kW
13. Tesla Model S - 72 amps - 17.2 kW - optional charger upgrade
14. Tesla MOdel X - see Model S options above
15. etc…s

only a few vehicles listed above even have the option to charge at 19.2 kW - and all o them will only charge at a rate of 6 kW when using the charge point chargers at Valley Fair mall in San Jose - except the Leaf - it will charge at 3.6 kW since 6 kW is too much for it.

a Nissan Leaf will always charge at 3.6 kW no matter how powerful the charger you plug it into is.
and your 19.2 kW Taycan will charge at 3.6 kW if it's plugged into a Nissan Leaf EV charger

the major charging networks non-fastDC chargers (Chargepoint, Blink, EVGo, Electrify America, Seca Connect, etc) all tend to be 40 or 30 amp EV chargers - so your big Powerful 19.2 kw Taycan is mostly likely going to be limited to 4 to 6 kW when away from home and attempting to use "public" L2 chargers from the major networks, or independent chargers installed in most businesses or hotels or golf courses or wineries…

19.2 kW chargers do existing in the wild in North America - but they are uncommon.
and 19.2 kW capable EV's are also uncommon which means there is little incentive to install them since so few EV's can fully utilize them...

fast charge rates are being pushed via FastDC Chargers which start at 17 kW and go all the way up to 350 kW - with the Taycan supporting 270 kW (I got 263 kW the other day Sunday may 2nd in Gilroy, ca at the EA chargers there it was wonderfully fast)

so frankly I've stopped caring about AC L2 charging rates - 48 amps is more than enough for 99% of usage - and even the cheapest EV supports at least 50 kW charge rates when using fastDC chargers - so I'm not optimistic anyone is going to "build out" more fast AC charging - it's just not the trend…there is a limited number of chargers in the wild that support it, and there is a limited number of vehicles that support it, and it's not necessary for common daily usage that is easily handled over night in 3 hours or less at 48/40/32 amp charging rates at home…

 

[atebit]

Thanks for the detailed replies! In my case, at the time my house was built, I had a Tesla Model S with dual on board AC chargers (an option Tesla no longer offers), so I ordered 400A service from my utility and had the electrician run a 100A sub panel into the garage for my 19.2 kW capable Tesla Wall Charger.

I just ordered a 60A Tesla Tap Mini from the J1772 store, so at least I should be able to benefit from the 11 kW charge rate at home.

IIRC it was around 2015/16-ish when Tesla discontinued offering dual on-board chargers; I think maybe they were starting to get concerned about battery degradation on the earlier Model S batteries. Plus “mainstream” EVs were so new c. 2013 (as well as very limited charging infrastructure) that there was a lot of range anxiety, which (at least in the Tesla community, but definitely NOT in the LEAF community ) was starting to go away 3 or so years later. But it was sure great to watch it ramp up to charge at nearly 60 miles/hour!

 

[J0EL]

Can you guys help me out here?
I keep hearing that every home is 100 to 200 amps.
Im doing my math based on the numbers on the breakers...
My Panel A adds up to 470 amps
My panel B adds up to 320 amps
Is this correct?
How do I know how much more amperage is available?
And will I be able to run a 100 amp based on this info?

 

[andrewket]

Thanks for the detailed replies! In my case, at the time my house was built, I had a Tesla Model S with dual on board AC chargers (an option Tesla no longer offers), so I ordered 400A service from my utility and had the electrician run a 100A sub panel into the garage for my 19.2 kW capable Tesla Wall Charger.

I just ordered a 60A Tesla Tap Mini from the J1772 store, so at least I should be able to benefit from the 11 kW charge rate at home.

IIRC it was around 2015/16-ish when Tesla discontinued offering dual on-board chargers; I think maybe they were starting to get concerned about battery degradation on the earlier Model S batteries. Plus “mainstream” EVs were so new c. 2013 (as well as very limited charging infrastructure) that there was a lot of range anxiety, which (at least in the Tesla community, but definitely NOT in the LEAF community ) was starting to go away 3 or so years later. But it was sure great to watch it ramp up to charge at nearly 60 miles/hour!

I also had dual chargers on my first and second S, and 72A “high amp charging” on my third. I also had it on our X’s. I have it on good authority that Tesla discontinued the option to simplify the build, reduce costs, reduce customer confusion (customers were ordering 72/80 charging but couldn’t support it at home), and lastly, reduce infrastructure failures due to improper installation. These failures were causing parts to melt and the occasional fire. It became a PR problem.

 

[atebit]

So your load center is typically stocked with branch circuit breakers in excess of what’s supplied by the utility. What I’m not seeing in your picture is the main breaker in each panel. that’s what you need to look at.

the idea is that you won’t draw anywhere near the rated capacity of all/most of those breakers at the same time, but the branch circuits themselves may periodically need close to that rating (say when your furnace motor or refrigerator compressor starts up).

also know that in most places you need to “derate” your charging branch circuit by 25%
since it’s considered a “continuous load” (constantly energized for 3+ hours). So for instance an EVSE that can comfortably draw 40A needs a minimum 50A circuit.

but I am not an electrician do you should ask a licensed one in your area for how to proceed. </disclaimer>

*Fixed That For Me

 

[Jhenson29]

Can you guys help me out here?
I keep hearing that every home is 100 to 200 amps.
Im doing my math based on the numbers on the breakers...
My Panel A adds up to 470 amps
My panel B adds up to 320 amps
Is this correct?
How do I know how much more amperage is available?
And will I be able to run a 100 amp based on this info?

The 100/200 amp service is referring to your incoming service. It may be something else also. It could be 150A or 400A or something else. You’d have to check the main breaker for your service.

The breakers in your sub panel can add up to more than your service because they are not all in use at full capacity at the same time. You need an electrician to come out and do a load calculation to determine your available capacity and what you are able to add to your panels.

For reference, I had a 200A service and 760A worth of breakers in my main panel to start with. But I still had enough load capacity to add a 125A feed to my garage for a additional sub panel for charging. I now have 885A of breakers in my panel.

 

[Jhenson29]

So your load center is typically stocked with branch circuit breakers in excess of what’s supplied by the utility. What I’m not seeing in your picture is the main breaker in each panel. that’s what you need to look at.

the idea is that you won’t draw anywhere near the rated capacity of all/most of those breakers at the same time, but the branch circuits themselves may periodically need close to that rating (say when your furnace motor or refrigerator compressor starts up).

also know that in most places you need to “derate” your charging branch circuit by 20% since it’s considered a “continuous load” (constantly energized for 3+ hours). So for instance an EVSE that can comfortably draw 40A needs a minimum 48A circuit. Since 48A circuit breakers aren’t common you’ll probably end up needing a 50A (or the much more common 60A) breaker and the wiring to match.

but I am not an electrician do you should ask a licensed one in your area for how to proceed. </disclaimer>

If I remember right, it’s that continuous loads need to be at 80%. So, that’s 20% under, not over, which means you actually do need the 50A (not 48) branch circuit for the 40A continuous load. I.e. you need to be 25% over, not 20%.

Edit: I just double checked and yes, it’s 25% over.

 

[J0EL]

Isn't this where my main breaker should be??

 

[atebit]

Agreed. Never seen a 48A residential breaker, anyway (though they may exist) but I’m pretty sure I have some double-pole 50A’s in my panel.

 

[atebit]

When I lived in NC my main breaker was outside at the service entrance/meter so the FD could turn it off if necessary.

 

[Jhenson29]

Isn't this where my main breaker should be??

As atebit says, it’s outside by your meter.

 

[daveo4EV]

Can you guys help me out here?
I keep hearing that every home is 100 to 200 amps.
Im doing my math based on the numbers on the breakers...
My Panel A adds up to 470 amps
My panel B adds up to 320 amps
Is this correct?
How do I know how much more amperage is available?
And will I be able to run a 100 amp based on this info?

the total number of breakers _ALWAYS_ adds up to more than your main feed - if everything was running at full capacity and every breaker was "maxed out" yeah you'd trip your main breaker, but that doesn't happen very often.

we'll need a picture of your "Main" breaker - but honestly mostly they pay attention to the "240V" breakers - of which I see:

60 amp
45 amp
30 amp

60 amp
45 amp
40 amp
30 amp
25 amp
20 amp

the other circuits are 120V 20's & 15's - lights & plugs that commonly do not come anywhere close to using the full capacity of the breaker.

you mostly likely have 200 amp service or more based on the number/capacity of your existing 240 volt breakers.

if you want to "add" an EV charger the best case would be a 50 amp breaker for a 40 amp charge rate _IF_ your service can handle it and it meets local electrical building codes - consult a qualified/licensed/bonded electrician for their advice & recommendation.

the issue is not total amps in the break boxes - it's how common would it be for any/all of those 240V breakers to be in use _AT THE SAME TIME_ - the only answer to that is in tracing what each of those big breakers "feed" - and then determine if those appliances/devices would likely be on and running near full capacity at the same time as your EV charger…

they use hardly any power/load if they are idle/off…it when they are running that power is being consumed and you are limited to the capacity of your main breaker.