SAE Publishes Charging Recommendation for Medium- and Heavy-Duty Electric Vehicles
The Society of Automotive Engineers developed a recommended practice for plug-in charging of heavy duty electric vehicles. The new standard was designed to offer a single vehicle charging coupler solution for three-phase and single-phase AC and DC charging.

The J3068 coupler was developed from existing international standards, which were extended to cover higher North American grid voltages and higher power levels. Photo: SAE
The Society of Automotive Engineers developed a recommended practice for plug-in charging of heavy duty electric vehicles. The new standard was designed to offer a single vehicle charging coupler solution for three-phase and single-phase AC and DC charging.
SAE approved a new, three-phase coupler for plug-in charging of electric vehicles, along with the organization’s recommended practice for plug-in charging of such vehicles.
Dubbed the J3068 Electric Vehicle Power Transfer System, the new coupler was developed from existing international standards, which were extended to cover higher North American grid voltages and higher power levels.
According to SAE, J3068 allows vehicles to fully utilize three-phase AC power where it is available and preferred, such as at commercial and industrial locations.
J3068 was developed in a consensus process by SAE International's Medium and Heavy Duty Vehicle Conductive Charging Task Force Committee, which is made up of more than 100 global experts from the automotive industry, utilities, charging equipment manufacturers, national laboratories, and academia.
"This new standard was designed to offer a single vehicle charging coupler solution for three-phase and single-phase AC and DC charging for a class of vehicles," said Rodney McGee, chief engineer of EV Projects at the University of Delaware and chair of the SAE Medium and Heavy Duty Vehicle Conductive Charging Task Force. "We wanted to combine this new approach for AC charging with 1000V DC charging based on existing SAE communication standards."
"The goals of J3068 include bringing a proven, mass produced three-phase charging coupler to North America, and establishing a low-cost, reliable communication and control protocol for AC with inherently high interoperability" said Jim McLaughlin, document sponsor and retired Mack Trucks electrical engineer. "High power AC charging has cost advantages in many use cases, and three-phase charging simplifies balancing of the power grid."
For more information about "J3068: Electric Vehicle Power Transfer System Using a Three-Phase Capable Coupler," or to purchase the standard, go to: https://www.sae.org/standards/content/j3068_201804/.
Related: Mack to Build Electric Refuse Trucks for New York City
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