Onboard charger: 19.2kw vs 150 kw/400v - which do I need?

[feye]

That said, I understand the 150kw on board charger is for public stations and much cheaper than the 19.2. So what exactly is the 19.2 kw for?

None of it. The 19.2 kW charger in your car would charge the battery in 5 hours instead of 9 hours. Do you need it? If so, must check with electrician and power supply company how much it cost.

The 150kW on board charger (for up to 400V) is useless, because all the new EA chargers are capable of pushing up to 350kW (always up to 800V).

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[TCT]

SImply to add clarity to this topic...

In light of the possibility that Tesla will open their superchargers in North America to everybody else by end of year : Tesla will open its charging network to all EV brands | Greenbiz ,

Does the 19.2Kw option now a "must have" a "nice to have" or still a "waste of money" in North America

I am asking only for destination chargers.

 

[daveo4EV]

Destination chargers are already “open” to non-Tesla’s _IF_ you have a TeslaTap/JDapter - they are simply Tesla L2 Wall chargers installed at various businesses - use of these chargers are at the discretion of the business owner at which they are installed.

these chargers are _NO_ different than the PMC+/PMCC/ClipperCreek/JuiceBox chargers we all installed in our personal garages - they are simply 240V EVSE’s installed at businesses for use by their customers. They are not part of a “network” and there is no billing or activation control on these chargers. they are really no different that a bare NEMA 14-50 plug. If the business owners allows you to “plug-in” power will flow and charge any EV allowed to physically access the charger. Billing is impossible (other than access control charges by the business) as these are residential grade chargers with no accounting or metering.

Tesla Designation Chargers are morally equivilant to Porsche giving away PMCC’s to any business that requested them for no charge. Once given away their use/installation is at the discretion of the business where they are installed.

one such Tesla Destination charger near me on the West Coast is:

Seascape Beach Resort
1 Seascape Resort Dr. Aptos CA. 95003

https://www.plugshare.com/location/58737
https://maps.apple.com/?ll=36.95065...AAK95QkAxAAAAQCB4XsA5AAAAAK95QkBBAAAAQCB4XsA=

Seascape Resort has 4 installed in underground parking garages - you can use them if you are resort guest and they are not occupied and you have an adapter - access is virtually uncontrolled - and they are barely monitored by hotel staff - pull up - park - plug-in and volia you’re charging.

they are 19.2 kW chargers

another location that has them in Calif is:

The Oaks Hotel & Suites
3000 Riverside Avenue, Paso Robles, CA 93446

https://www.plugshare.com/location/12343
https://maps.apple.com/?ll=35.64504...A4JDSQUAxAAAAABQsXsA5AAAA4JDSQUBBAAAAABQsXsA=

similar to Seascape - access is “lightly” controlled - they are 48 amp chargers - if you have the TeslaTap or similar - you’ll be allowed to charger if you can park and plug-in. Access again is “lightly” controlled by hotel staff - charge rate is 11 kW.

the majority of 19.2 kW chargers to be found in North America I’ll postulate are Tesla Destination chargers - as to if this option is useful that would depend on if you think you would ever visit a business that has them. I would check with the Tesla Destination charger network in your region and/or plug-share to determine if any of them are actually 19.2 kW chargers and you anticipate visiting that business in the future.

I still think there are technical problems with the 19.2 kW charger option from Porsche (no plug&charge support if you option this charger) and I know of one forum member that is on his 3rd 19.2 kW charger under warranty from Porsche.

you Taycan already comes with an 11 kW charger and if you visit a Tesla destination site with a 19.2 kW charger your Taycan will charge at 11 kW - I know this because that is my home setup. I have 100 amp Tesla Gen2 wall chargers - these _ARE_ the exact charging hardware installed at most Tesla Destination charger sites.

it’s still a toss up as to if this $1600 option is actually worth it in North America - the real question is if you visit a site that has them and you have a TeslaTap and the business allows you to use the charger - do you care that your Taycan will charge faster while it’s parked and your not using it? For example in a hotel scenario - I’m there overnight and I honestly don’t care.

Tesla has two separate networks:

1. Supercharger network - 480V FastDC plug&charge proprietary network - this requires a Tesla account, billing, and a Supercharger “enabled” vehicle (i.e. it has to speak the protocol to talkt to the charger) - this network is installed, maintained, monitored, run by Tesla Corp.
2. Tesla Destination chargers - residential L2 AC chargers installed by various businesses (restaurants, hotels, golf courses, wineries, health clubs, etc….) and access is controlled by the business that has installed this charger - the chargers are simple L2 AC chargers for business customer use - Tesla provides charging hardware for “free” to businesses if they request it, but the chargers themselves are run and maintained by the businesses that have they installed - Tesla Corp. has _NO_ controll over these chargers and does _NOT_ maintain/monitor them. There is typically _NO_ billing or accounting associated with these chargers.

#1 is currently not useable by non-Teslas in North America - this may change in the future - we’ll see if this comes to pass
#2 is accessable to non-Tesla via existing simple TeslaTap/JDpater hardware dongle - charging amps at these sites typically range from 16 to 80 amps (3.8 kW to 19.2 kW) - there is NO billing, account, app. YMMV is word of the day with regards to these chargers and you should contact the business that owns them prior to visiting to make sure you’ll be allowed to use them.

 

[XLR82XS]

Thanks both! Is the onboard charger something that can be added later for the Taycan?

According to Porsche - No. I cannot be retrofitted after the car is built.

 

[kort]

Be aware that the 19.2 kw onboard charger had issues. It causes the plug and charge not to work and in my case causes many fail to charge issues at EA chargers. Unless Porsche has corrected their flawed hardware I would avoid this option

 

[kort]

SImply to add clarity to this topic...

In light of the possibility that Tesla will open their superchargers in North America to everybody else by end of year : Tesla will open its charging network to all EV brands | Greenbiz ,

Does the 19.2Kw option now a "must have" a "nice to have" or still a "waste of money" in North America

I am asking only for destination chargers.

Superchargers are dc charging, the 19.2 kw onboard unit is for AC charges

 

[Jhenson29]

I still think there are technical problems with the 19.2 kW charger option from Porsche (no plug&charge support if you option this charger) and I know of one forum member that is on his 3rd 19.2 kW charger under warranty from Porsche.

I’m under the impression that P&C will work with the 19.2kW Charger for MY22. Do you have information to the contrary?

I find it very unlikely that they pulled the option on MY21 for this issue and then just said “oh well” and put it back out there with the same issue. I also think it’s unlikely they’ll find the same issue after release (“Oops! …I did it again.”)

Regarding someone being on their 3rd Charger…generally when the same component fails twice in row…I start looking at other components. But I don’t have any more specifics, so I don’t know.

 

[Windpower]

#2 is accessable to non-Tesla via existing simple TeslaTap/JDpater hardware dongle - charging amps at these sites typically range from 16 to 80 amps (3.8 kW to 19.2 kW)

Question: if you plug a 11kw capable car into a 19.2kw Tesla destination EVSE supply, will the car’s internal 11kw charger be damaged? I know that with the Tesla charger, there’s a handshake between the car and the EVSE which sets the supply current. Does the same happen with a non-Tesla car? If there is no handshake, how does the high power EVSE know to limit the supply current to what the car can handle?

 

[daveo4EV]

Question: if you plug a 11kw capable car into a 19.2kw Tesla destination EVSE supply, will the car’s internal 11kw charger be damaged? I know that with the Tesla charger, there’s a handshake between the car and the EVSE which sets the supply current. Does the same happen with a non-Tesla car? If there is no handshake, how does the high power EVSE know to limit the supply current to what the car can handle?

no damage - for all EV charger the EVSE advertises it’s maximum rate and the car then adjust it’s rate to to match - if the EVSE can do “more” the car will only pull what it can - if the EVSE can do “less” the car will not ask for more than the EVSE can provide

this is all by design and keeps everything working smoothly.

plug an 11 kW (48 amp) EV into:

• 16 amp EVSE (Nissan Leaf) - car will pull 16 amps
• 12 amp EVSE 120V (default GM Bolt EVSE) - car will only pull 12 amps # 120 volt
• 80 amp EVSE @240 volts (19.2 kW charger) - car will only pull 48 amps since that’s all it can handle

 

[Jhenson29]

how does the high power EVSE know to limit the supply current to what the car can handle?

I just want to expand on what @daveo4EV said.

The answer to this specific question is: it doesn’t. It has no knowledge, nor any need for knowledge, of what the car can handle.

Because the EVSE doesn’t (and can’t) directly limit the current*.

The EVSE just signals it’s limit to the car via the control pilot.

The car ultimately controls the current as it’s the load. The car can’t be “damaged” by being “sent” too much current because the car isn’t “sent” current; it’s provided a voltage and the car pulls current.

So, if the car does get damaged from too much current (barring a voltage issue….which the EVSE also doesn’t control*), it’s the car’s fault.

*other than opening the contactor…which limits it to zero…

 

[Windpower]

Good explanations. Thanks!

 

[daveo4EV]

I also believe but can not confirm that a poorly behaving EV (not EVSE) could "over tax" an EVSE

example:

• EVSE (external charging hardware) reports to car it can do 16 amps (20 amp breaker)
• EV charger inside the car sees this an understands this but goes ahead and "pulls current" for 32 amps

now this is wrong, and cleary a bug in the EV charging software and it should not happen - but from the EVSE's I've inspected there is NOTHING to stop/prevent/restrict 32 amps from happening - at this point in time the _ONLY_ thing that will keep that from getting out of control is the circuit-breaker/fuse upstream from the EVSE (or perhaps in high quality EVSE's their own breaker/fuse)

but for most of the EVSE internals Iv'e seen they are simple pass through devices where the input power is blocked by a relay (on/off) but once the relay is "closed" allowing power to "flow" they are simple passthrough devices that will just deliver what ever current is requested by the vehicle

now I have no way to test this and have no desire to test this - but I"m simply making a point that the EVSE (the external chargers) is pretty simple electrically - and I do not believe it can, or even tries, to protect itself from a mis-behaving vehicle.

it's really no different that plugging 4 microwaves into a normal 15 amp household circuit - (20 amps = 2400 watts - 4 microwaves = 4000 watts - fire all 4 of those bad boys off at the same time and the ONLY thing that will keep the whole thing from melting is the circuit breaker which should trip - there is no actual "throttle" on electrical wires to prevent too much current.

the only thing in the world keeping your Taycan from overloading an External EVSE is Porsche's charging software and it's implementation of the J-1772 protocol - if your Taycan requested 48 amp from a 12 amp EVSE - I'm pretty sure one of two things would happen:

1. for some period of time 48 amps would "flow" - and hopefully the 15 amp circuit breaker would trip cutting off the power to the EVSE and preventing more power flowing to the vehicle
2. 48 amps would flow and if the fuse/circuit-breaker doesn't trip - wires would melt and potentialy short out and potentially cause a fire - this would be bad

EVSE's and their implmentations are pretty dumb/passive devices - they control very very little of the charging process - and are only flow controler for allowing/disallowing power to flow under command of the vehicle - they rely pretty heavily on the vehicle's charging software/implmentation to behave correctly and very few protections against a "misbehaving" EV - the only "safety" mechanism in them tends to be the fuse/circuit breaker installed as part of the EV overall circuit.

but at the end of the day there is very little to prevent any EV from requesting too much power just like nothing will prevent you from plugging in 4 microwaves to a single 15 amp 120 volt circuit - we all hope/pray/rely on the circuit breaker at that point - cause nothing else will prevent the wires from overheating and melting.

NOTE: to date I have never ever heard/seen/rumored an EV that behaves in this manner and it wold be a serious manufacturer defect if it did and a recall would certainly be in order - this is a hypothetical thought exercise.

 

[Windpower]

• EVSE (external charging hardware) reports to car it can do 16 amps (20 amp breaker)
• EV charger inside the car sees this an understands this but goes ahead and "pulls current" for 32 amps

I hope the 20 amp breaker will trip. Keep in mind the circuit breaker is designed to protect the wires which go from the breaker to the equipment, so if the equipment tries to pull 32amps from 20amp capable wires, the breaker hopefully will trip.

 

[daveo4EV]

I hope the 20 amp breaker will trip. Keep in mind the circuit breaker is designed to protect the wires which go from the breaker to the equipment, so if the equipment tries to pull 32amps from 20amp capable wires, the breaker hopefully will trip.

I agree.

 

[Jhenson29]

I also believe but can not confirm that a poorly behaving EV (not EVSE) could "over tax" an EVSE

example:

• EVSE (external charging hardware) reports to car it can do 16 amps (20 amp breaker)
• EV charger inside the car sees this an understands this but goes ahead and "pulls current" for 32 amps

now this is wrong, and cleary a bug in the EV charging software and it should not happen - but from the EVSE's I've inspected there is NOTHING to stop/prevent/restrict 32 amps from happening - at this point in time the _ONLY_ thing that will keep that from getting out of control is the circuit-breaker/fuse upstream from the EVSE (or perhaps in high quality EVSE's their own breaker/fuse)

but for most of the EVSE internals Iv'e seen they are simple pass through devices where the input power is blocked by a relay (on/off) but once the relay is "closed" allowing power to "flow" they are simple passthrough devices that will just deliver what ever current is requested by the vehicle

now I have no way to test this and have no desire to test this - but I"m simply making a point that the EVSE (the external chargers) is pretty simple electrically - and I do not believe it can, or even tries, to protect itself from a mis-behaving vehicle.

it's really no different that plugging 4 microwaves into a normal 15 amp household circuit - (20 amps = 2400 watts - 4 microwaves = 4000 watts - fire all 4 of those bad boys off at the same time and the ONLY thing that will keep the whole thing from melting is the circuit breaker which should trip - there is no actual "throttle" on electrical wires to prevent too much current.

the only thing in the world keeping your Taycan from overloading an External EVSE is Porsche's charging software and it's implementation of the J-1772 protocol - if your Taycan requested 48 amp from a 12 amp EVSE - I'm pretty sure one of two things would happen:

1. for some period of time 48 amps would "flow" - and hopefully the 15 amp circuit breaker would trip cutting off the power to the EVSE and preventing more power flowing to the vehicle
2. 48 amps would flow and if the fuse/circuit-breaker doesn't trip - wires would melt and potentialy short out and potentially cause a fire - this would be bad

EVSE's and their implmentations are pretty dumb/passive devices - they control very very little of the charging process - and are only flow controler for allowing/disallowing power to flow under command of the vehicle - they rely pretty heavily on the vehicle's charging software/implmentation to behave correctly and very few protections against a "misbehaving" EV - the only "safety" mechanism in them tends to be the fuse/circuit breaker installed as part of the EV overall circuit.

but at the end of the day there is very little to prevent any EV from requesting too much power just like nothing will prevent you from plugging in 4 microwaves to a single 15 amp 120 volt circuit - we all hope/pray/rely on the circuit breaker at that point - cause nothing else will prevent the wires from overheating and melting.

NOTE: to date I have never ever heard/seen/rumored an EV that behaves in this manner and it wold be a serious manufacturer defect if it did and a recall would certainly be in order - this is a hypothetical thought exercise.

The circuit breaker protects the EVSE. It would be redundant and unnecessary to have anything additional in the EVSE, other than possibly a fuse for the control circuit, but this would likely be supplemental overcurrent protection vs branch circuit overcurrent protection (different standards). It does require proper installation, including the wire and breaker, but we have to assume that's correct. If we're including incorrect installation in possible faults, then the sky's the limit.

If the EV pulls to much current, the OCPD trips. That's it. That is the protection.

However, it is possible for either the EVSE or EV to cause this. The EVSE could cause this by having a fault in the PMW for the 1khz max current signal that caused it to signal a higher than available current. Or the EV could have a fault in reading the signal. Either of these cases could result in too much current draw.

Where I think you could have an issue is if there was a mild overload (say 45 or 48 amps) on a EVSE that was supposedly 40-amps but used under-sized wire. Anybody know of any of those??? ??

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