What is a J3068 charger?

It's a 3-phase coupler for AC charging. 277V * 80A per phase * 3 ph = 66 kW, and it appears to be the same as the EU IEC 62196 connector (based on the sign). The standard is still a work-in-process, so I think this is likely to be a prototype.

Presumably, they'd design it so an EU Tesla could plug into this connector and could charge at 22 kW (since the chargers are only 32A per phase in Model S).

The plug depicted on the sign looks like a Mennekes Type 2 plug which I thought was only used in Europe.

J3068 (WIP) Electric Vehicle Power Transfer System Using a Three-phase Capable Coupler - SAE International

SAE J3068 | www.openchargealliance.org.nl

J3068 is a working group of SAE international.
Electric Vehicle Power Transfer System Using a Three-phase Capable Coupler
The existing SAE conductive charging standards do not allow for the vehicle to utilize three-phase AC power. Three-phase power transfer is targeted at commercial and industrial locations or other areas where such power is available. Grid stability is enhanced by presenting a symmetric three phase load, especially at high power levels.
Category:
Liaison: standard setting, defining organisation or network organisation that has supportive interest in OCA standards


Contact name:
Rodney T. McGee - Chief Engineer - EV Projects - Chairman SAE J3068


Email address:
[email protected]


Company visiting address:
University of Delaware
139 The Green
118 Evans Hall
Newark DE 19716
+1-302-831-3278 Work

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My guess is that this is for electric buses, or other fleet vehicles. Interesting that there is interest in this - at that power level, wouldn't some DC charging standard be better?

Cosmacelf said:

My guess is that this is for electric buses, or other fleet vehicles...

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That was my guess too. I have to upload photos of a plug i saw for a plug-in hybrid ferry. The manufacturer hasn't responded to my replies for technical specs, I guess they figure I'm not in the market for a ship.

Cosmacelf said:

My guess is that this is for electric buses, or other fleet vehicles. Interesting that there is interest in this - at that power level, wouldn't some DC charging standard be better?

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Yes, it's why you probably won't find anything appear beyond 80A on AC. It's a big waste to have a bunch of big chargers distributed in every single vehicle; put the chargers at the charging points.

I have a slightly different guess. I suspect this is the way to shoehorn the IEC 62196 standard into the US, in an effort to try and create a global standard based on Mennekes (which is a better connector design than J1772 but is still rather horrible from a customer experience perspective). But maybe I'm just a bit cynical today.

University of Delaware is home to the EVgrid V2G special Mini-Es.
Perhaps those plugs are related.

UD, state partner to create electric vehicle charging station network

V2G Home

http://publicaa.ansi.org/sites/apdl/evsp/ANSI_EVSP_Progress_Report_Nov_2014.pdf

TEG said:

University of Delaware is home to the EVgrid V2G special Mini-Es.
Perhaps those plugs are related.

UD, state partner to create electric vehicle charging station network

V2G Home

http://publicaa.ansi.org/sites/apdl/evsp/ANSI_EVSP_Progress_Report_Nov_2014.pdf

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I wouldn't be surprised if they are.

I'm conflicted on whether we really need that in the US, given the availability of high-current L-L split-phase and lack of three phase infrastructure in many/most places.

But having a standard is good, I suppose. I just wish it was more elegant and user friendly. I'm a big fan of the Tesla02 design, it's just elegant and hard to screw up. Even my 6-year-old could plug the car in when he was 5. I know he can't do that with CHAdeMO or J1772 (because of the round connector w key - remember old DIN plugs, "spin 'till you get it in"), and I think he'd have a problem lining everything up on a Mennekes to get it to fit right. It's better for orientation because it's not symmetrically-round, but it requires that you insert it into the connector while keeping it straight - no rotation, no vertical or horizontal angles. The rounded edges of Tesla's receptacle combined with the shape allows the connector to orient as you're pushing it in.

It's one of those things that Tesla doesn't trumpet, but it's an elegant design that should be called out, like the work apple did with Lightning and what USB3c is doing.

I see no advantages going over 20kW AC, private car or bus/truck. In terms of multiple vehicles (at least 3)
I see little advantages to give 3 phases for each vehicle rather than 1 phase per one vehicle. All 3
phases can be in use if there are at least 3 vehicles.
AFAIK most AC to DC chargers for EVs in the world are limited to 265V between neutral and phase.
If I remember correctly it is due to common semiconductors and what is their maximum voltage.

It's very easy to change AC voltage from 277V to 240V. Much cheaper than making new kind of onboard chargers.

Keep in mind that DC station that handles 66kW DC doesn't cost more than 66kW onboard charger.
In terms of fleet charging it is possible to have one charger for multiple vehicles. Vehicles connected in the evening
and charger shuffles according to needs automatically.

There is already some discussion about this in the Charging Standards sub-forum here:
J3068 - 3 Phase A/C Charging for North America

It has been pointed out that some electric shuttle buses have 60kW on-board chargers. The standard allegedly goes up to 165kW with higher voltages and the possibility of the EVSE to have multiple line voltages available that can be selected by signaling from the vehicle.

Why do they have that onboard charger? Is it using the same onboard inverter that is used for motor?
Same method is used by Renault Zoe. This is why this small city EV has "43kW" onboard charger.
Yes, Zoe can accept more than twice as much AC power compared to any Tesla.
Also this allows higher input voltage than 265V as motor is driven at much higher voltage than that.

arnis said:

Why do they have that onboard charger? Is it using the same onboard inverter that is used for motor?
Same method is used by Renault Zoe. This is why this small city EV has "43kW" onboard charger.
Yes, Zoe can accept more than twice as much AC power compared to any Tesla.
Also this allows higher input voltage than 265V as motor is driven at much higher voltage than that.

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The selection of the on-board charger must have had to do with the planned routes and energy consumption. My understanding is that the Mountain View Community Shuttle is plugged in for an hour or so during lunchtime and overnight. If the overnight charge is not enough to run the whole day, then they must make up the difference during the limited hours available at lunchtime. The shuttle has no DC charging capability.

miimura said:

The shuttle has no DC charging capability.

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All vehicles have DC-charging capability. It requires direct connection instead of indirect.
Even ICE vehicles can be charged with DC power.

If there would be 2 shuttles parked for the night, it would be cheaper to have one 50kW CCS station.
Rather than having two stand-alone onboard chargers on those vehicles.
If 50kW is not enough then 62.5kW CCS station. Or 100kW. Doesn't matter.

The only rational explanation is 2in1 inverter-charger.

arnis said:

All vehicles have DC-charging capability. It requires direct connection instead of indirect.
Even ICE vehicles can be charged with DC power.

If there would be 2 shuttles parked for the night, it would be cheaper to have one 50kW CCS station.
Rather than having two stand-alone onboard chargers on those vehicles.
If 50kW is not enough then 62.5kW CCS station. Or 100kW. Doesn't matter.

The only rational explanation is 2in1 inverter-charger.

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In order to charge by DCFC you must implement the charger protocol and integrate with the BMS to ensure that the DC current pushed into the battery by the external charging station is safe and within the parameters of the battery chemistry. This is a significant development effort that is probably not practical for these conversion-like vehicles.

If you want to charge multiple vehicles overnight, unattended, then the number of chargers required is the same whether you have on-board or external chargers.

miimura said:

This is a significant development effort that is probably not practical for these conversion-like vehicles.

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Did you mean the same protocol that is used by the onboard charger? It's the same software. CC-CV with 100ms response rate.

miimura said:

If you want to charge multiple vehicles overnight, unattended, then the number of chargers required is the same whether you have on-board or external chargers.

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Incorrect. One off-board DC-charger for all vehicles. Charging sequentially for example. Though there must be as many plugs as there are vehicles. All plugs connected to the same charger. Charger does the switching.

arnis said:

Did you mean the same protocol that is used by the onboard charger? It's the same software. CC-CV with 100ms response rate.

Incorrect. One off-board DC-charger for all vehicles. Charging sequentially for example. Though there must be as many plugs as there are vehicles. All plugs connected to the same charger. Charger does the switching.

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Supporting DCFC across all the commercially available chargers is a huge task. One example is how long it took Tesla to debug and release the CHAdeMO adapter. Even though there's a standard, some of the chargers installed in the field do very strange things.

Which commercially available DCFC solution has multiple plugs and can automatically charge multiple vehicles simultaneously or sequentially?

miimura said:

Which commercially available DCFC solution has multiple plugs and can automatically charge multiple vehicles simultaneously or sequentially?

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AFAIK, all of them. If there is one vehicle connected to ChaDeMo and one at CCS, the second one will be at stand by until the first one has charged up. Some may switch power during first vehicle ramping down, that depends on how many power modules are there and programming.

The one in my country has ChaDeMo and Type2 AC. Due to grid limitations, Type2 is also limited by software until ChaDeMo vehicle ramps down. Maximum current draw is what is preset to each charger unit. And that is according to main circuit breaker which is usually dependant on grid connection.

arnis said:

AFAIK, all of them. If there is one vehicle connected to ChaDeMo and one at CCS, the second one will be at stand by until the first one has charged up. Some may switch power during first vehicle ramping down, that depends on how many power modules are there and programming.

The one in my country has ChaDeMo and Type2 AC. Due to grid limitations, Type2 is also limited by software until ChaDeMo vehicle ramps down. Maximum current draw is what is preset to each charger unit. And that is according to main circuit breaker which is usually dependant on grid connection.

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The key point in my statement was "automatically". None of the stations I've seen can do this in an automatic and unattended manner. I'm not saying it's not possible to build one, I'm just saying that I don't think there is a fleet oriented DCFC commercially available today that can charge multiple vehicles in parallel or sequentially while unattended.

miimura said:

The key point in my statement was "automatically". None of the stations I've seen can do this in an automatic and unattended manner. I'm not saying it's not possible to build one, I'm just saying that I don't think there is a fleet oriented DCFC commercially available today that can charge multiple vehicles in parallel or sequentially while unattended.

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Doen't the Superchargers do that?
My understanding is that the Supercharger outlets are paired with two vehicles connected to a single DCFC station. The two vehicles are charged in parallel with priority given to the first to plug in and the second tapers up as the first tapers down.