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System Lets Fifthwheel/Kingpin Coupling Process Be Monitored from Inside Cab

With the patented Electronic Lock Indicator (ELI) system from The Holland Group Inc, drivers now can monitor and manage the fifthwheel and kingpin coupling process from inside a cab. This technology verifies the fifthwheel and kingpin locking sequence and then transfers data to the driver in real time through an icon-based display in the dashboard or driver-side rear-view mirror. The rear-view mirror option was developed jointly with Hadley Products of Grandville MI.

When the tractor starts, the ELI system automatically diagnoses coupling status through impact-resistant and environmentally sealed magnetic proximity sensors installed on the fifthwheel top plate. The sensors transfer coupling status to the driver as lighted icons.

If a tractor is not connected to a trailer and the fifthwheel is in the ready-to-couple position, a yellow fifthwheel icon appears on the display. If fifthwheel and kingpin are securely locked, the driver sees green fifthwheel and lock icons that remain visible for several minutes. But if there is a problem due to improper coupling, the system warns the driver using red fifthwheel and lock icons. It also identifies the source of the problem and provides the driver with directions to solve the problem via single-digit error codes. Holland's testing results reveal:

  • An improvement in driver and equipment safety by reducing incidents of improper coupling. This ELI display supplements visual inspection and pull-test procedures and provides redundant safety checks that confirm proper coupling.

  • A driver and equipment management tool. The system automatically records and stores data from the most recent 250 to 300 coupling attempts.

Data reveal the number of successful couples, total coupling attempts, success ratio (average number of attempts per couple), and the most consecutive number of unsuccessful attempts. Details of any failed coupling attempt can be displayed showing the sensor status and sequence that caused the error.

Currently, the Holland ELI system is available as an option on new Holland 3500 Series fifthwheels (FW33 and FW35 models).

For full details, contact Holland Group, 467 Ottawa Ave, PO Box 2099, Holland MI 49422-2099.

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