[North America] - this is getting embarrassing - Porsche nerfing/neutering the PMCC via OTA update?

[W1NGE]

with apologies to @JohnK since he thinks I'm posting too much

thanks to @JP38 for the following update:




here is summary of the facts so far:

• Porsche pushed OTA update for the PMCC version 3014 in the past couple of days
• this version sets your PMCC's default charge rate to 20 amps - this will charge any EV/Hybrid slower than the original 40 amp specification (or 24 amp spec if you're using a NEMA xx-30 supply cable)
• this makes the default charge rate 4.8 kW - NOT 9.6 kW
• this setting can be temporarily overridden via the LCD setting pages on the PMCC's LCD screen - but this setting will be "lost" if the PMCC is powered down or unplugged
  • the PMCC's webportal also can set this value higher - but again it's only temporary
• in my case logging in with the "home" user name password and setting the amps to 40 amps does not "retain" the setting across reboots - I tested this with my unit software version 3014 - using chrome on MacOS
• in my case logging in with the "customer service" user name and password and setting the amps to 40 amps does not retain the settings across a reboot - I tested this with my unit software version 3014
• connecting to the unit's webportal is tricky for the average user - since default browser security settings these days tend to refuse to connect to websites with self signed SSL certficates…this is a hurdle for the average user - but problem doesn't matter because the webportal override is temporary just like the LCD screen settings.
• after the OTA update is initially installed the LCD screen charger rate setting screen is Locked and no adjustment can be made - it's been reported that simply rebooting the PMCC restores the ability to temporarily adjust charge rate - but still the adjustment is lost each time the PMCC powers back on and the 20 amp default is restored.
• this update appears to only affect North American units - European PMCC's still appear to be the excellent product years of data and positive customer experience have indicated and no change in charging behavior in these units is apparent or reported at this time - this so far only appears to affect North American units
  • also this change only affects PMCC units (the one's with WiFi and an LCD screen) - if your Porsche EVSE does not have an LCD screen then so far your specific unit is not affected by this change (since it doesn't have OTA software updates).
• Release notes have not yet been provided - but may be posted when the update image is posted on Porsche's PMCC downloads site - thanks to @AndiL for this suggestion
• I have not yet discovered a method to adjust the charge rate overrides the default 20 amp value across a PMCC reboot or idle shut down
• Unless you manually adjust the charging rate each time you use your PMCC it is now effectively a 4.8 kW EVSE vs. it's original 9.6 kW specifcation - and it can only temporarily be adjusted above it's new default 4.8 kW charging rate.
• given that nature of this sort of change reasoned speculation is that Porsche has made this change for safety reasons although no specific reasons have been provided by Porsche.
• this change ONLY affects the PMCC EVSE - it does not change your Taycan's (or Hybrid's) maximum charge rate - but you vehicle will charge slower when using an updated software version 3014 PMCC in it's default state
• if your PMCC is not connected to WiFi you are unlikely to have received the update - so no change in behavior for you
• if your PMCC has auto update disabled you are unlikely to have received the update - so no change in behavior for you
  • however even with auto updates disabled - if your PMCC is on wifi - an unmodified PMCC will "pester" you with a full screen request to apply the update "now" - you can dismiss this "pester" message, but so far I've found no way to suppress it.
• if your PMCC has been unused and "off" the past couple of days you are unlikely to have received the update - but if you turn it on and do not want the update you'll need to be quick to disable auto-updates and disconnect from wifi when you power it up - using the settings menu on the LCD screen.
• no word or suggestion yet from Porsche as to if this is a permanent change pending some future parts updates or if there is even any follow up expected - stay tuned

people who are tired of hearing about this issue are welcome to ignore this thread.

Fantastic summary.

As you know I have had the same update and no change to the default 32A setting for the EU model - I still have a 22kW PMCC.

One thing, if you don't turn off your EVSE (why would you unless transporting it?) then your 40A setting is retained, right?

If that's the case then is the issue not a mild inconvenience and not a major inconvenience if PMCC is left powered on and has been set to 40A?

I have never powered off my PMCC in 2 years and just let it lapse onto sleep mode when not in use

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[daveo4EV]

Fantastic summary.

As you know I have had the same update and no change to the default 32A setting for the EU model - I still have a 22kW PMCC.

One thing, if you don't turn off your EVSE (why would you unless transporting it?) then your 40A setting is retained, right?

If that's the case then is the issue not a mild inconvenience and not a major inconvenience if PMCC is left powered on and has been set to 40A?

I have never powered off my PMCC in 2 years and just let it lapse onto sleep mode when not in use

sleep mode resets the default to 20 amps - external power blips reset the amps which can occur at any time

 

[W1NGE]

sleep mode resets the default to 20 amps - external power blips reset the amps which can occur at any time

Ok that's clear!

So you could disable sleep mode but no real failsafe for unintended power cuts (fortunately we don't tend to have these).

 

[daveo4EV]

Ok that's clear!

So you could disable sleep mode but no real failsafe for unintended power cuts (fortunately we don't tend to have these).

basically the unit is no longer reliably a 9.6 kW unit - it can revert to 4.8 kW for a number of reasons outside the control of the user - this can occur during a charging session which was started "late" due to departure time calculations based on the 9.6 kW charge rate - leaving you "short" of target charge % due to change in charge rate during the charging session (power blip)…

while it can be overridden the override is very fragile and temporary - so there is no method that I have discovered to effectively "PIN" the unit to being a 9.6 kW charger if it's running software version 3014…this is simply stupid in my opinion.

I have no idea why anyone at Porsche thought this was a good idea - and based on official communications up to this date it would appear this is the new "normal" as no additional planned/future updates have been announced.

it's now a 4.8 kW charger - plain and simple - since that is the only configuration in which it's behavior will remain predictable with out user intervention - it is no longer a fire & forget EVSE for 9.6 kW…no pun intended.

there is zero evidence/hint/rumor that any similar change will be coming to units outside North America - the other region's PMCCs seemto be a much stronger product offering with no need for these sorts of misguided software updates.

 

[daveo4EV]

basically the unit is no longer reliably a 9.6 kW unit - it can revert to 4.8 kW for a number of reasons outside the control of the user - this can occur during a charging session which was started "late" due to departure time calculations based on the 9.6 kW charge rate - leaving you "short" of target charge % due to change in charge rate during the charging session (power blip)…

while it can be overridden the override is very fragile and temporary - so there is no method that I have discovered to effectively "PIN" the unit to being a 9.6 kW charger if it's running software version 3014…this is simply stupid in my opinion.

I have no idea why anyone at Porsche thought this was a good idea - and based on official communications up to this date it would appear this is the new "normal" as no additional planned/future updates have been announced.

it's now a 4.8 kW charger - plain an simple - since that is the only configuration in which it's behavior will not change.

there is zero evidence/hint/rumor that any similar change will be coming to units outside North America - the other region's PMCCs seemto be a much stronger product offering with no need for these sorts of misguided software updates.

the ability to continue charging after a brief/short/medium/long power outage is actually a reliability/resiliency concern and one addressed directly as a feature by at least one competitive EVSE product as noted below:

https://store.clippercreek.com/hcs-50-hcs-50P-40-amp-ev-charging-station
Automatic Circuit Reclosure: In the event of a minor power fault, the built-in reclosure timer will continue re-checking conditions and begin charging again as soon as possible (if your car needs charging)

reliable and consistent charging even in the face of power interruptions is an important feature of an EVSE - one should not wake up to a partially charged EV just because there was a brief or not so brief power outage during a scheduled charging session.

it is a design consideration and goal to have an EVSE be resilient and work to keep charging the vehicle even in adverse condtions - the PMCC was fragile in this regard before this update (internal breakers tripping, unit overheating, phantom grounding issues - all leading to a halted charging session) and requires manual intervention to resume charging - possibly with no notice and while you were asleep and unable to respond.

this update has amplified any fragility issues and now makes the charger revert to a slower charge rate for issues beyond the user's controls.

it lacks resiliency that products 1/10th it's cost possess.

 

[W1NGE]

basically the unit is no longer reliably a 9.6 kW unit - it can revert to 4.8 kW for a number of reasons outside the control of the user - this can occur during a charging session which was started "late" due to departure time calculations based on the 9.6 kW charge rate - leaving you "short" of target charge % due to change in charge rate during the charging session (power blip)…

while it can be overridden the override is very fragile and temporary - so there is no method that I have discovered to effectively "PIN" the unit to being a 9.6 kW charger if it's running software version 3014…this is simply stupid in my opinion.

I have no idea why anyone at Porsche thought this was a good idea - and based on official communications up to this date it would appear this is the new "normal" as no additional planned/future updates have been announced.

it's now a 4.8 kW charger - plain an simple - since that is the only configuration in which it's behavior will not change.

there is zero evidence/hint/rumor that any similar change will be coming to units outside North America - the other region's PMCCs seemto be a much stronger product offering with no need for these sorts of misguided software updates.

Fully understand the outcome and limitation. I guess my angle is to look for ways litigation may not be successful (I'm no lawyer and no knowledge of US law whatsoever) and whilst not full remediation there clearly is one as mentioned above.

Porsche / OEM have made a conscious decision to impose this restriction but not totally shut the door on rendering the EVSE a 100% 4.8kW device.

Communication on this has been atrocious no question.

 

[ciaranob]

Guys - please forgive me for not going back through the highly detailed info being shared here re this latest development but just wanted to ask a basic question and (if answer Yes) throw in my 2c solution.

1. The Question: I assume that this USA specific 'power throttling' was done not just to the PMCC but also to the basic PMC+ correct?

I had the uPdate done recently and they had requested my PMC+ too - when I just now plugged mine in at home, the default startup setting was 50% and this is new I believe - so again assume the dealership tech set this new default.

2. My Solution: I basically long pressed the 'Charge Status' button once and the Energy Manager button lighted up, flashing yellow. I then long pressed the 'Charge Status' button again and the unit switched Charge Status from 50% to 100% (a 'menu' function I presume it always had).

I then plugged it in the car and it charged at the full 9.6 with 8.6kW to the car i.e. two long presses switched the unit from default 50% back to 100% - SUPER simple. Am I missing something? No web/network access needed whatsoever and it doesn't matter to me if I have to repeat this simple step to get to 100% each time I start it up.

I then left the unit plugged in the Nema 14-50 socket but not plugged into the car to test sleep mode. After 20 minutes returned to see the PMC+ 100% asleep - woke it up and it retained the 100% Charge Status I had previously set. I have not yet tried fully unplugging and re-starting but can do later.

For ref I have a ChargePoint Home Flex hardwired in my home garage so never use the Porsche EVSE to charge at home - it has only been used at destinations with an available NEMA 14-50 and then literally a couple of times.

APOLOGIES if I just stated something obvious or that had already been noted - but this double long press process takes just seconds and is not a major impediment to my using the Porsche PMC+ albeit in my use case, rarely if ever needed.
Cheers, C.

 

[daveo4EV]

Guys - please forgive me for not going back through the highly detailed info being shared here re this latest development but just wanted to ask a basic question and (if answer Yes) throw in my 2c solution.

1. The Question: I assume that this USA specific 'power throttling' was done not just to the PMCC but also to the basic PMC+ correct?

I had the uPdate done recently and they had my PMC+ too - when I just now plugged mine in at home, the default startup setting was 50% and this is new I believe - so again assume the dealership tech set this new default.

2. My Solution: I basically long pressed the 'Charge Status' button once and the Energy Manager button lighted up, flashing yellow. I then long pressed the 'Charge State' button again and the unit switched Charge Status from 50% to 100% (a function I presume it always had).

I then plugged it in the car and it charged at the full 9.6 with 8.6kW to the car i.e. two long presses switched the unit from default 50% back to 100% - SUPER simple. Am I missing something? No web/network access needed whatsoever and it doesn't matter to me if I have to repeat this simple step to get to 100% each time I start it up.

For ref I have a ChargePoint Home Flex hardwired in my home garage so never use the Porsche EVSE to charge at home - it has only been used at destinations with an available NEMA 14-50 and then literally a couple of times.

APOLOGIES if I just stated something obvious or that had already been noted - but this double long press process takes just seconds and is not a major impediment to my using the Porsche PMC+ albeit in my use case, rarely if ever needed.
Cheers, C.

PMC+ is a bit easier to override - but it will still revert to 50% upon startup if it's been updated to new firmware - since it doesn't have wifi I"m not sure if there is a firmware update for it.

if you set it to 100% - plug your car in and walk away - and grid-power blips - you'll be back to the slower charge rate (if the PMC+ has been updated)

so the 100% setting is "fragile" and if you're away from the car it can revert to 4.8 kW setting…

if you use the PMCC/PMC+ infrequently this update is no big deal

if this is your main EVSE and you want a 9.6 kW EVSE the PMC+/PMCC no longer fit the bill unless you baby-sit them to keep them in their now optional 9.6 kW configuration

basically they are both now 4.8 kW EVSE's that are optionally 9.6 kW "boost" mode which will revert back to 4.8 kW in a number of common scenarios.

 

[ciaranob]

PMC+ is a bit easier to override - but it will still revert to 50% upon startup if it's been updated to new firmware - since it doesn't have wifi I"m not sure if there is a firmware update for it.

if you set it to 100% - plug your car in and walk away - and grid-power blips - you'll be back to the slower charge rate (if the PMC+ has been updated)

so the 100% setting is "fragile" and if you're away from the car it can revert to 4.8 kW setting…

if you use the PMCC/PMC+ infrequently this update is no big deal

if this is your main EVSE and you want a 9.6 kW EVSE the PMC+/PMCC no longer fit the bill unless you baby-sit them to keep them in their now optional 9.6 kW configuration

basically they are both now 4.8 kW EVSE's that are optionally 9.6 kW "boost" mode which will revert back to 4.8 kW in a number of common scenarios.

As of now it is fine for my use so I'll keep it as my destination charger and the switch from 50 to 100 just not an issue for me.

One thing though - I mentioned above (a later edit) that even after sleep mode initiated in the PMC+ (yes it is an updated unit). it retained the 100% setting I had set. I can't really simulate a power surge/blip but suspect the same would hold true in such an event.

So curious, you have seen this behavior whereby an updated PMC+ with a grid surge/blip has reset the unit back to 50% after setting to 100%? Or are you possibly inferring this might happen from what you have seen on your PMCC?

EDIT - I just went back out after unplugging the PMC+ for over 30 mins and replugged it back in - it booted up and is still set to 100%! So now feeling confident that even a power surge would likely not revert it to 50%

 

[daveo4EV]

As of now it is fine for my use so I'll keep it as my destination charger and the switch from 50 to 100 just not an issue for me.

One thing though - I mentioned above (a later edit) that even after sleep mode initiated in the PMC+ (yes it is an updated unit). it retained the 100% setting I had set. I can't really simulate a power surge/blip but suspect the same would hold true in such an event.

So curious, you have seen this behavior whereby an updated PMC+ with a grid surge/blip has reset the unit back to 50% after setting to 100%? Or are you possibly inferring this might happen from what you have seen on your PMCC?

inferring from the PMCC

it's 100% fact that the PMCC's amp setting is fragile (firmware version 3014)…basically the unit drops back to 50% at the drop of a hat…

if the PMC+ does not do this then it's not that bad

 

[ciaranob]

inferring from the PMCC

it's 100% fact that the PMCC's amp setting is fragile (firmware version 3014)…basically the unit drops back to 50% at the drop of a hat…

if the PMC+ does not do this then it's not that bad

Hey - yes indeed - we're responding as I am real time testing - I added an EDIT above - the PMC+ has actually retained the 100% setting after fully unplugging and replugging in after 30mins - so the PMC+ seems good to go.

 

[slothinker]

What's PMC+ ?

 

[ciaranob]

What's PMC+ ?

The 'basic' portable charger that comes as std with any new Taycan - it has lighted buttons when plugged in but no LCD display or other advanced features that come with the PMCC..

 

[Pjjameso]

Asked this earlier but may have been missed… If Porsche replaced the cables would this solve the issue?

 

[daveo4EV]

Asked this earlier but may have been missed… If Porsche replaced the cables would this solve the issue?

we don't know - I know other EVSE's do not have similar problems with similar plugs - but it's pretty clear Porsche thinks/knows there is a problem given the OTA update setting units to 50% - the issues was pretty throughly hashed out 2 years ago in this thread…

https://www.taycanforum.com/forum/th...eat-data.1940/

the first post in the above thread has a picture of my unit from July of 2020 (over 2 years ago and shared with porsche via Dealer/Service Network) demonstrating a 162F surface temperature @ 64F ambient temperatures - that's a 98F rise from 2 hours of charging - and right in line with predictions from EE AWG tables about expected temperature rise for 10 AWG wire at 40 amps - so if ambient temp is 90F or 95F - you can expect this cable to demonstrate a temperature of 193F surface temperature…that's pretty toasty and right in line with expected thermals for this class of wire gauge and the expected current loads - cables like this are rated 105C or 221F for temperature limits - and 193F is less than 221F - but that's awfully close to thermal "limits" for this sort of stuff - I'm not an EE or materials engineer and don't know what it means to exceed the limit (wire melt? insulation fail? breaker trip? cheap plastic NEMA socket plastic melt?)

all I know is cooler is better…and other EVSE's running at a full 9.6 kW rarely crack 120F surface temps of their cables even in 95F ambient conditions…

the conclusion seems to be Porsche choose a "safe" to keep using the same wire gauge for their North American power supply cables (10 gauge AWG) but that it was a poor choice given it's foreseeable thermal characteristics @ 40 amps - coupling that poor choice with a cheap/wonky/poorly-installed NEMA plugs is probably two separate problems when brought together that amplify each other…no one side of the problem is solely responsible but mix them together and it can go poorly…

this supply cable has been in the VW/Audi/Porschde parts bin for at least 8 years and was originally used with 16/32 amp EVSE's for their Hybrid's including the 918 Spyder - I doubt anyone remotely considered "updating" the part to a higher gauge wire, and a cursory examination of EE design tables show that 10 gauge wire is safe if properly insulated for 9.6 kW loads - but the thermal rise for this load is expected to be high -but not unsafe

my opinion is: 10 AWG wire is safe but a poor choice given foreseeable thermal characteristics for a _MOBILE_ 9.6 kW/40 amp product that is going to be handled by bare hands shortly after/during normal use.

couple that expected/predicted thermal rise with an enclosed decorative box and some higher ambient temps in warmer climates and the temperature of the supply cable can be down right hot - but not electrically unsafe…

what we can state is:

• other 9.6 kW EVSE's in North America tend to ship with 8 or 6 AWG supply cables rather than the 10 AWG choice Porsche is shipping with
  • Porsche is unique in the North American market of 9.6 kW/40 amp EVSE's for NEMA 14-50/6-50 AC power supply cable - other vendors I own or have encountered have 8 or 6 AWG wire for their 9.6 kW EVSEs
  • Porsche also ships their 14-30/6-30 power supply cables with exactly the same 10 AWG wire - in the case of 30 amp circuits that wire only needs to carry 24 amp loads
  • in July 2020 PMCC Porsche's "silver" label on these supply cables comes clearly marked as rated for "16 amps" - that's is another peculiarity here, and a label like that can not be considered authoritative - 16 amps matches the 3.6 kW charge rate of many of their early/existing Hybrid vehicles (including the 918 Spyder)
    • since I do not have a "newer" model PMCC I do not know if Porsche is shipping newer supply cables with a different silver label…the picture in the link is from the unit delivered with my 2020 Taycan Turbo
    • [UPDATE] - my 2021 Cayenne PMCC has a new and improved label but the same 10 AWG wire.
  • as I said this part has been in the parts supply chain for quite awhile - has porsche just reused this cable over and over and over again - and added different plug-heads onto it - and done a simple review in EE table's for wire "safety"? EE Tables will show you the wire is safe, but you need to consider thermal temps if you are considering the wire being handled - did they not consider the "mobile" aspect of their charger after running at 40 amps for 9.5 hours to charge a Taycan
    • Hybrid's running at 16/24 amps rarely take more than 4 hours until the battery is full- a less demanding application.
• using other EVSE's with these same plugs demonstrate fewer problems
• and Porsche buried in this tech update is a recommendation for an "industrial" grade NEMA plug (Hubble is called out by name) and is the same recommendation as Tesla, Lucid, Rivian

I think we can say a cheap non-industrial grade NEMA 14-50/6-50 socket will not improve things…

there are at least 3 separate problems with the PMC+/PMCC units - but they are hard to deal with individually…

1. a poor choice of 10 AWG supply cable wire for a 40 amp EVSE? - cord can exceed 160F surface temps in normal use in mild ambient temperatures - over 190F has been reported…
2. cheap/poorly installed NEMA sockets (not under porches control) - we have known issue of "melted" plug sockets
3. the unit DOES overheat and shutdown in normal use in certain climates and usage patterns

other EVSE's do not seem to demonstrate similar problems…

the 3 problem above are not universally true in all circumstances, but can occur separately or together in certain circumstances…the ONLY solution porsche has is to:

1. redesign/replace the unit
2. reduce the electrical draw to reduce the thermal loads
3. withdraw the units from service and direct customers to alternate non-Porsche EVSE vendors

my $200 Tesla Corded Charger running at a full 9.6 kW does not - melt sockets (cheap or otherwise), overheat, or have a power supply cable that reaches 190F in normal use - go figure.

is Porsche's choice of 10 AWG wire the core cause here for all these issues?

I'm not qualified to comment (and few on the internet are) but I think we can say it's not helping…but it may not be the problem.

Porsche has chosen to lower the charging capacity of their unit rather than swap the unit for a new design or upgrade the cable. No one outside of Porsche knows what alternatives were discussed prior to the software update release - and if Porsche has analyzed the problem and determined what if any hardware fix could be made - or if they even care to pursue a fix.

at the moment the PMCC is 4.8 kW by default and "boosting" it to 9.6 kW is possible but fragile given it's reversion to 4.8 kW under various circumstance - unattended you can only rely on the PMCC charging at a rate of 4.8 kW.

charging at a full 9.6 kW rate after plugging in and walking away to the end of a charging session is a surprise outcome given the recent software update.

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