IT IS MISSION ACCOMPLISHED for The Maintenance Council task force on tractor-trailer communications.
The group, charged with evaluating and recommending a system that complies with the National Highway Traffic Safety Administration (NHTSA) regulation for an in-cab trailer ABS malfunction light, made its choice and closed up shop. The announcement was made at the TMC meeting held June 21-24 in Milwaukee.
As the Society of Automotive Engineers (SAE), Truck Trailer Manufacturers Association (TTMA), and the Truck Manufacturers Association (TMA) did before them, members of The Maintenance Council chose to support the technology of PLC4TRUCKS as the means of meeting the NHTSA mandate and of providing power to a wide range of trailer-mounted electronic devices in the future.
Oren Summer, chairman of the task force, thanked TTMA and TMA for their work. He also recognized Truck-Lite Corporation for its development of technology similar to that being used on PLC4TRUCKS. Truck-Lite was one of three companies competing with PLC4TRUCKS to produce the technology that would become the standard method for bidirectional communication between tractors and trailers.
With tractor and trailer manufacturing groups lining up behind the PLC4TRUCKS, the TMC recommendation helps clear the way for the technology to become the standard for the trucking industry.
The decision is in sharp contrast to the previous TMC meeting held three months earlier. During that meeting, PLC4TRUCKS and three other parties gave presentations on four separate, incompatible technologies. Summer, president of FleetNet America, admitted leaving the meeting not knowing what direction TMC would take on this issue.
"I think we finally have closure on this issue," he said. "As far as I am concerned, we are through with this task force."
Prior to the June TMC meeting, Truck-Lite announced it was supporting the PLC4TRUCKS consortium. Air-Weigh, a developer of a competing system, had supported PLC4TRUCKS almost from the beginning while simultaneously promoting its own technology.
What's Next The work of the TMC task force may be finished, but a significant amount of testing remains to be done before PLC4TRUCKS can be ready for general fleet use. Here is the schedule that the PLC4TRUCKS consortium has developed for getting the system to the marketplace:
January 1998-Demonstrate the functionality of the system.
Spring 1998-Circuits produced and testing begins.
Summer 1998-Testing of various electronic controls and on vehicles begins.
Winter 1998-99-winter testing, especially of ABS controls.
1999-Start of production and continued testing, especially in large fleets.
Winter 1999-2000-Confirmation of winter testing.
2000-Continued production
2001-Mandate begins.
Multiple Connectors PLC4TRUCKS offers multiple benefits, Freightliner's Paul Menig said in a presentation to TMC-including the ability to meet the in-cab malfunction lamp requirement by using a single J560 connector. But under certain circumstances, trailers still may require multiple connectors, he said. These circumstances include:
* Battery power from the tractor must go directly to the trailer.
* Special connections are required for products such as cameras, motors, pumps, and trailer tracking.
* Delivering alternating current to trailer.
* Excessively heavy electrical loads.
* A separate circuit for trailer ABS is required.
* An additional ground connection is needed.
* Providing J1939 data to the trailer.
How It Works One benefit of PLC4TRUCKS is that it requires only a single connector for most applications, Menig said.
The system will power trailer ABS with Pin 7-the blue circuit. PLC4TRUCKS does not add any new computers. Circuitry will be buried inside the ABS units.
The system performs the bulb check required by NHTSA. The lamp, however, only goes on when ignition is activated, not whenever power goes off.
If the trailer ABS malfunctions, the ECU on the trailer is designed to detect it. The trailer ABS then sends a signal to the tractor ABS, which subsequently turns on the malfunction lamp. If the trailer is uncoupled or the fault goes away, the light will go out.
The computer chips in the tractor and trailer ABS function through the use of the same J1587/J1708 protocol that truck manufacturers utilize for truck-mounted electronic components.
Other tractor-trailer communication functions can be added, according to Dave Hammes of Allied Signal. PLC4TRUCKS can accommodate up to 22 nodes.
A trailer ABS malfunction lamp on the dash will not immediately eliminate the need for a trailer-mounted lamp. NHTSA will continue to require that such a lamp be mounted on trailers until 2008.
Signing On The PLC4TRUCKS consortium members and affiliated companies include Air-Weigh, Allied Signal, Cummins Engine, Dialight, Dorsey Trailers, Eaton, Federal Mogul, Freightliner, Highway Master, Intellon, Kysor Medallion, Mack Trucks, Meritor-WABCO, Parasoft Computing Solutions, Phillips Industries, Qualcomm, Thermo-King, Truck-Lite, Vansco, Vehicle Monitor Corporation, and Wabash National.
"We listened to you," Hammes told the TMC audience. "PLC4TRUCKS is an inexpensive solution that works, and one that will accommodate future needs."
"We won't have to buy a bunch of connectors or rewire a bunch of trailers," Summers added.