KarTrak ACI

KarTrak, sometimes KarTrak ACI (for Automatic Car Identification) is a colored bar code system designed to automatically identify rail cars and other rolling stock. KarTrak was made a requirement in North America, but technical problems led to abandonment of the system in the late 1970s.

In the late 1960s, railroads in North America began searching for a system that would allow them to automatically identify rail cars and other rolling stock. Through the efforts of the Association of American Railroads (AAR), a number of companies developed Automatic equipment identification (AEI) systems. The AAR selected four systems for extensive field tests. General Electric developed an RFID system, ABEX a microwave system, Wabco a black and white barcode system, and General Telephone and Electronics (GTE) a color barcode system called KarTrak. All those systems, except the RFID system, had labels that were mounted on each side of the rail car and a trackside scanner.

After the initial field tests, the ABEX, Wabco, and the GTE KarTrak ACI systems were selected for a head-to-head accuracy test on the Pennsylvania Railroad, at Spruce Creek PA. The KarTrak system was declared the winner and selected by the AAR as the standard.

Starting in 1967 all railcar owners were required by the AAR to install ACI labels on their cars. This requirement led to full-scale implementation of the ACI system in the early 1970s. By 1975 90% of all railcars were labeled. The read rate was about 80%, which means that after seven years of service 10% of the labels had failed for reasons such as physical damage and dirt accumulation. The dirt accumulation was most evident on flatcars that had low-mounted labels.

The AAR had recognized from their field tests that periodic inspection and label maintenance would be requirements to maintain a high level of label readability. Regulations were instituted for label inspection and repair whenever a railcar was in the repair shop, which on average happened every two years.

Unfortunately the maintenance program never gained sufficient compliance. Without maintenance the read rate failed to improve, and the KarTrak system was abandoned by 1977. Because of this failure, the railroad industry did not seriously search for another system to identify rail cars until the mid-1980s.

KarTrak ACI tags consisted of a plate with 13 horizontal labels, which could have 13 different forms. In addition to the labels for numbers 0-9, three special labels existed; start and stop labels to mark the beginning and end of the code, and "10" as a check label.

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