‘Smart’ links for tractor-trailers

Designs affecting the 75-year-old tractor-trailer electrical connector, one of them an improvement and the other an enhancement to enable “smart” trailer operations, have been released by manufacturers. One can be used now, and the other is a candidate in the quest for a new connector that could supersede the current seven-pin connector, called J560 for its Society of Automotive Engineers designation.

The tractor-trailer connector carries power to trailer lights and signals for anti-lock braking systems, and the current design dates to 1951. It has been topical over the last several years because some truck operators want more circuits to carry signals to and from additional equipment envisioned for future “smart” trailers.

A group within the Technology & Maintenance Council of the American Trucking Associations has been studying proposed designs that could replace the current J560 connector now used on nearly every tractor-trailer in North America. At least six designs have been shown, and the group is reportedly down to three.

Members of the group hope to gain agreement on one design that will become an industry standard, with adoption by SAE and, therefore, truck and trailer builders. Agreement on a new connector is probably years away. However, the current connector will continue in use for many years, participants say.

Repairable plug

To do away with disruptions caused by damage to current connectors, Peterson Manufacturing is offering a Repairable J560-style two-piece plug and cable for installation on a tractor. The repairable plug includes an end portion that attaches to the inner portion with a turn-lock motion, explained Al Anderson, vice president of sales and marketing. If damaged by being dragged or crushed, it simply twists off, and a new plug quickly twists on.

The existing cable can still be used, and the tractor is not sidelined, assuming a replacement plug is nearby, maybe stowed in the tractor’s tool box. The new Peterson plug-and-cable assembly substitutes for a common connector cable in current use, and works with J560 sockets on the nose of any semitrailer. It is now available through truck parts stores or direct from Peterson.

Advanced plug and socket

The new-style plug from Tectran Manufacturing retains the current J560 circular design with seven round ports, and adds four ethernet-type ports and two round accessory ports. The four ports can handle high-speed data transfer between tractor and trailer to support special functions, like advanced safety systems, cameras and telematics, and the two accessory ports can carry 24 volts for trailer equipment requiring more than the usual 12 volts.

A corresponding socket on the nose of the trailer contains the male pins for the plug. It also has a spring-loaded stainless-steel locking mechanism and a circular “gutter” to drain moisture that gets past a seal between plug and socket, explained Jarod Scherer, Tectran’s president and CEO.

Including the seven J560 ports allows “backward compatibility” with existing trailers, he said. Thus, a new tractor’s connector can mate with the socket on an old trailer, and an old tractor’s connector will mate with the advanced socket on a new trailer. In such pairings, any smart functions on a trailer would not be active. Eventually, smart tractors will pull smart trailers so the advanced functions can be used.

Volvo Trucks is backing the Tectran design because “a modern truck is a highly sophisticated, connected machine,” said Magnus Gustafson, vice president of connected services. “The trailer has to evolve at the same pace. This collaboration allows us to rethink how tractors and trailers communicate and hopefully establish a new connector standard for North America.”

Volvo and Tectran patents are open, so anyone in the trucking industry may use this design, Scherer said. If TMC and SAE adopt this design, other truck builders and electrical component manufacturers can also adopt them. LL