EVSE engineer Ned Funnell explains the advantages of the J3068 charging standard.
It may be a cliché, but it’s true: when it comes to EV charging, one size does not fit all. For commercial EV fleets, deploying the most appropriate charging system for their duty cycles can not only save money, it may enable them to deploy more EVs, and/or to sidestep utility upgrade bottlenecks.
Medium- and heavy-duty EVs need higher power levels than passenger cars, but they don’t necessarily need the fastest charging hardware available. For example, if you have a fleet of trucks that you know are going to be sitting in the depot overnight, every night, you do not need to charge them in two hours.
Today, DC charging is often considered the only viable option for charging trucks or buses, because most AC charging in North America (J1772 and J3400/NACS) operates at roughly 10-15 kW or less. However, DC charging stations cost considerably more than Level 2 AC stations, and, depending on a site’s existing electrical service, may also require transformers, which cost money, take up space, and may require long waits for installation.
Many infrastructure planners may not realize that there is another option, which can enable fleets to get into the sweet spot for charging power. The J3068 standard enables three-phase AC charging across a broad power range. A common 480-volt, 63-amp implementation delivers about 52 kW, while higher-power configurations are possible. Using LIN-CP communication and active cooling, the specification’s limit of 160 A would enable 480 V AC charging at 131 kW, potentially at much lower infrastructure cost than DC charging.
Charging with 3-phase AC is rare in the US, but it’s a proven approach used in Europe, Asia and elsewhere, and there are mature supply chains for the hardware.
When we first connected with Ned Funnell, he was working for EVSE manufacturer Lincoln Electric. Now he’s a Product Manager at Zaptec, a Norwegian company that builds AC chargers and related hardware. He has become something of an EVangelist for the J3068 standard. His rallying cry: Fleet depots don’t have to deal with the power limitations of J1772/NACS forever.
The SAE J3068 standard, aka “Electric Vehicle Power Transfer System Using a Three-Phase Capable Coupler,” defines a system for using a charging connector capable of transferring single-phase and three-phase AC power as well as DC power, and defines a digital communication protocol for control.
As Mr. Funnell explains, with three-phase power, instead of a single voltage between just two conductors, you have three voltages among three conductors. Physics (or magic—same thing?) tells us that adding a conductor lets you increase your power by 73%, at the same current and same voltage. Moving to a higher voltage, which J3068 allows but does not require, adds another multiplier.
Does implementing J3068 charging require an expensive utility service upgrade? Rather the reverse—the power provided at many industrial properties in the US is 480 V 3-phase AC. Using J1772 requires a step-down transformer, but J3068 lets you send 480 V 3-phase power right to the vehicle, giving you over 50 kW of charging power while saving a lot of copper.
The J3068 standard enables three-phase AC charging across a broad power range. A common 480-volt, 63-amp implementation delivers about 52 kW, while higher-power configurations are possible.
Charged: When did you first get interested in the J3068 standard?
Ned Funnell: Before I worked at Lincoln Electric, I was a charging solution architect for a company called Electrada, a fleet charging infrastructure developer. In that role I was faced with the heavy trade-offs between different charging levels.
For example, if you want to use AC charging for something like a box truck, you’re limited to single-phase and you’re almost always on 208-volt power at commercial sites, so you can’t really count on more than about 15 kilowatts. You’re flowing 80 amps, and stuff gets really hot—the connectors couldn’t hack it. But to make the jump up to DC charging, even if you only need 25 kilowatts, usually brings a substantial increase in cost, and you’ve got to have 480-volt power. [Editor’s note: Most DC fast chargers require 480-volt inputs, but Power Innovations International makes chargers that can accept a range of input voltages.]
I learned about J3068, which is based on the Type 2 charging standard used in Europe and globally, and I saw a lot of advantages to it. It’s not something that I see competing with J1772 or CCS1 for the private vehicle market, but for fleets that depend on their own in-depot charging infrastructure, it seems like it would be a big win.
Charged: What do we call this?
Ned Funnell: I just call it J3068, or three-phase Level 2 charging. I’m not aware of any other fun name for it.
Charged: Well, perhaps you should invent a fun, catchy name. I suspect we’re going to hear a lot more about it, because it seems like a great way for fleets to get more bang for their charging buck.
Ned Funnell: Yeah. As an example, let’s take a fleet depot where they’re going to be bringing in additional power, and they can get whatever spec they want. If you’re putting in, say, 100 electric delivery vehicles, and you have to install 100 DC chargers for those, that’s going to be very expensive. But you don’t need to do that because you’ve got all this off-shift time. Those trucks are sitting overnight for at least eight hours.
However, AC charging is problematic. Level 2 chargers will nominally do 9.9 kW on a 208-volt supply, which will get you charged in about 9 to 10 hours. And that’s adequate. But running that at 48 amps all the time, those connectors don’t last long, and changing the cable is often not very practical, so you’re changing the entire Level 2 EVSE if anything is damaged.
By going to a medium level and using the sensible way to transmit power, which is three-phase AC for anything double-digit kilowatts, you can sidestep all those problems. You’re not paying for the DC charger, and you’re not encountering the penalties of trying to squeeze over 10 kilowatts through single-phase power. This is what they do in Europe and Asia. It’s a common, sensible approach.
By going to a medium level and using the sensible way to transmit power, which is three-phase AC for anything double-digit kilowatts, you can sidestep all those problems.
In the US, unfortunately, back in 2009, the California Air Resources Board (CARB) selected a standard for charging based on the concept of suburban families buying EVs. That’s how we ended up with J1772, which is incredibly limiting for fleet charging.
Charged: So the commercial fleet industry is trying to work with a standard that was originally developed for residential charging?
Ned Funnell: Yeah. CARB, back in the day, worked with a couple different manufacturers, and a Japanese company called Yazaki came up with what we now call J1772. Three-phase wasn’t in the picture because the North American grid generally doesn’t bring it to single-family homes. Meanwhile in Europe, they reused the existing Type 2 Mennekes connector that was already in common use. They’ve got three-phase everywhere, so they defaulted to that, but we didn’t and we’re now paying the price for it.
Charged: So, in Europe, all the AC power is three-phase?
Ned Funnell: To clarify, we’re talking about distribution to sites, not within buildings. It would be more accurate to say that three-phase power trickles down through the European distribution grid much more deeply than it does in the US. Anywhere you’re sending power over long distances, it’s three-phase. But when you get into residences, back in the day, in the US they would save copper by only sending out one of the three phases. In Europe their distances are shorter, so it made more sense to bring three-phase power to the end users. It’s not everywhere, but it’s much more common.
The applications where I see J3068 being useful are almost exclusively fleets. The properties that fleets are operating out of, 95% of the time, already have three-phase. If they’re operating a fleet of any size, they’re going to need a utility upgrade to get the amount of power they need. But having three-phase already on site means that this is just a utility swapping a transformer and a contractor putting in a bigger panel, rather than an expensive line extension.
The applications where I see J3068 being useful are almost exclusively fleets. The properties that fleets are operating out of, 95% of the time, already have three-phase.
Charged: Does this require replacing the chargers? Or the transformer?
Ned Funnell: You might not need to change any of the electrical infrastructure all the way up to the panel. In a conventional fleet depot now, those panels are served with three-phase power, and it comes in at 208 volts. But then each individual Level 2 charger is served by one of the three phases. Stall A is on phase A, the next stall is on phase B, and so on. What needs to change is mostly on the vehicle. The port on the vehicle needs to be a J3068 connector and the onboard charger of the vehicle needs to be ready to accept three-phase at high power.
The charging industry basically already does this, and so does the vehicle industry in Europe. If you buy a Porsche or a BMW in Europe, you’re going to have that same common 11 kW onboard charging spec. But how they get it in Europe is not 48 amps at 240 volts. They’re using only 16 amps at 400 volts, three-phase. The European grid runs on 400/230 volts (the line-to-line voltage and line-to-neutral voltage). Here in the US we’ve usually got 208/120 volts, so we’re already starting off at half the voltage. Then when you add that one extra conductor, you can transmit 73% more power, even if you don’t increase the voltage. You can also increase the voltage and get a lot more power.
Fleet trucks could keep the CCS1 port for DC charging capability—just put a J3068 port next to it, as Range Energy has done on their powered trailer, and you can then charge at up to 43 kilowatts on AC power. Actually, in the US, you get 50 kilowatts by feeding the 480 volts directly to the vehicle.
Now, a common critique is that, if you want to have 50 kW charging, you have to have this big honking onboard charger on the vehicle. And in the short to medium term that’s a fair critique because, if an OEM wanted to go this way, they would go to their OBC vendor and say, “Can you give us the OBC you sell in Europe that accepts three-phase power?”
There are some on the market that do this, and there’s going to be a higher cost. Some Chinese manufacturers are integrating the onboard charger, drive inverter, DC/DC converter and other power electronics into a single assembly, and some designs can reuse inverter or motor hardware during charging.
Regen braking also sends three-phase machine power through the inverter toward the battery, which is why some of that hardware can be reused for AC charging.
Charged: If the inverter can function as the OBC, then why do you need the OBC?
Ned Funnell: You really don’t. BYD has a 12-in-one unit that includes the drive inverter, the OBC, the DC/DC converter and several other components. Basically everything that changes current happens in that box, and it happens with the minimum viable shared set of power electronics. The US has stuck with the tried-and-true, proven-though-inefficient method, but eliminating a separate OBC is more than technically viable.
Charged: Let’s talk about some companies that are implementing J3068 today. One is Range Energy, makers of an electric-powered semi-trailer, which we covered in our July-September 2025 issue.
Ned Funnell: The main reason why it works especially well in their situation is that refrigerated trailers also need power. The vast majority get it from diesel today, but they can also bring three-phase power to the trailer. These depots where the refrigerated trailers are sitting often already have a big panel ready to provide three-phase 480-volt power, typically at 30 amps.
They need to connect power to the trailer one way or another to keep the box cold. The default way to do that is with three-phase power in the depot, and J3068 actually solves a big problem there, because the industry has not agreed on a standard connector. There is no one plug that works for all refrigerated trailers. I’ve got a friend, Matt Srnec at Thermo King, who is advocating for the refrigerated trailer industry to adopt J3068 as the standard for all refrigerated trailers that are using three-phase power.
Charged: I understand that curbside charging pioneer it’s electric, which we covered in our July-September 2024 issue, is using J3068 for a different reason.
Ned Funnell: Yes. The other side of this is that you get detachable cable charging. In Europe, many Level 2 chargers on the street or in a parking lot do not have cables attached to them—the charger has a socket with a J3068 connector. There are companies that see enough advantage in the socketed bring-your-own-cable arrangement that they’re using J3068 in the US just for that purpose, even without any intention to put three-phase power through it.
Charged: So, the cable you use with it’s electric has 3068 on the charger end, and either your J1772 or your NACS on the vehicle end. But for three-phase fleet charging you’d need the J3068 plug on the vehicle side too, right?
Ned Funnell: Yeah. You would see this installed in fleet depots where you have a detachable J3068 on both ends. You don’t have to do that—you can have the cable attached to the charging station. But there’s still an advantage to a detachable cable for fleets. Even though it’s “behind the fence,” so they’re not so worried about vandalism, the cables and connectors wear out pretty quickly with the J1772 standard, and the typical way to correct that is to replace the entire EVSE. If you have a detachable cable on both ends you can simply have the driver grab a new cable.
Charged: Any other companies using three-phase Level 2 charging?
Ned Funnell: I can’t talk about it, but I’ve been told that a major agricultural equipment manufacturer is trialing J3068 for their off-highway equipment. Again, that’s going to be in places where three-phase is already available. There are more trade-offs with a DC charger, because you’re going to have this unit that either needs to be permanently installed or put on something and lugged around. The idea of a much more lightweight Level 2 EVSE that you can just plug into a receptacle wherever you are would be attractive to them.
Harbinger Motors could really benefit from this—they’re almost the perfect application for it.
Charged: I’m a big fan of Harbinger, which we covered in January. Commercial EV startups have been dropping like fruit flies, but CEO John Harris told me their sales keep growing. Why is three-phase Level 2 charging the perfect fit for Harbinger?
Ned Funnell: Well, the energy requirements that they have are just right. This is going to be overkill for a Chevy Bolt, but the power level isn’t high enough for a Class 8 truck. You want the middle range—Class 3 through 5 vehicles, where it’s got a few hours in the depot, so 50 kW charging can replenish all the energy needed. That’s exactly Harbinger’s niche, they’re selling exclusively to fleets, and their vehicles are going into locations where three-phase power is already common.
Charged: That brings up a larger point, which is right-sizing the charging capacity. Companies say, “We want the fastest charging we can get,” but they may be spending more than they need to because their duty cycle doesn’t require really fast charging.
Ned Funnell: Yeah. Especially if they are in a situation where they have to use DC power, because the 10-15 kW that you can realistically get through the J1772 plug right now is not adequate. They are then probably buying a 50 or a 60 kW charger, and they have to go to their utility to request that capacity, times however many trucks they have, whether they need that much or not, just because that’s the size of DC charger that’s available. Even if their operations only require 25 kilowatts, and even if they intend to limit those chargers to 25 kilowatts for demand charge purposes, they still have to plan for the smallest-size DC charger that meets their needs. So there’s a big risk of overspending on capacity that you don’t need, especially in this kind of messy lower-middle range.
Here’s another issue. When you ask for a certain amount of power from the utility, you don’t always have the option of getting it at whatever voltage you want. In the US you’ve got 208 volts and you’ve got 480 volts. For a depot, you may want 208-volt power because that’s what your trucks need for Level 2 charging. But if the utility is pushing you towards 480 volts because that’s their standard voltage for sites of your size, and that’s the transformers they have around, you have to place additional step-down transformers, a huge additional cost and often a lead-time constraint, in order to get the 208- or 240-volt power that you actually need for the vehicles. There’s a lot of copper in these charging depots that’s unnecessary in a world where you can choose to give the vehicle 480-volt power. And there’s already a market out there of OBCs that companies can buy from the European market, that are already ready for the 480-volt market here.
There’s a lot of copper in these charging depots that’s unnecessary in a world where you can choose to give the vehicle 480-volt power.
Charged: If you don’t mind my asking, do you have a professional interest in promoting this? Or is this just something that you’d like to see happen for the common good?
Ned Funnell: Basically the latter. I might profit from it in some way if I make myself the prophet of J3068 and then it happens. May get some pats on the back. But I don’t have any financial stake with any organization that’s promoting this.
Charged: Congratulations on your new job in Norway, the EV capital of Europe. Can you tell us a little about what you’re doing at Zaptec?
Ned Funnell: I’m Product Manager for Installation and Commissioning. Zaptec is a manufacturer of AC charging hardware and the rest of the ecosystem. My move to Zaptec is quite timely for this subject—I’m now working for Europe’s leading manufacturer of 3-phase AC charging stations. Zaptec has a phase-balancing technology that allows you to use all three phases and get the advantages of having that higher power with the reduced current. But there are some vehicles that can only accept single-phase input. In that case, those vehicles always pull from one of the three phases, and that creates a huge problem because if you have several of those vehicles in one spot, you’ll end up overloading one phase and be at your limit for the entire service.
So Zaptec has a technology that enables the charger itself to internally switch things around so that the single-phase charging EV is going to be on one of the other two phases, and it’ll actively balance that across a whole site so that, no matter what your mix of three-phase or single-phase vehicles is, you’re going to be able to maximize the utilization of that service there without overloading one of the phases.
They’ve actually been doing this for quite a long time, and they’ve got tens of thousands of chargers installed that are using this technology.
This article first appeared in Issue 76 – Subscribe now.
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