General Guidelines

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Important: The gas detection system must be powered at all times.

The gas detection system must be wired directly into the 12V batteries so that it can only be powered off by disconnecting the 12V batteries.

When servicing the vehicle, disconnect the 12V batteries only when necessary and do not leave them disconnected for extended periods of time.

A USA Pro Shoreline multizone combustible gas detection system is standard equipment on an eCascadia. The system is designed to give early warning of a high-voltage battery thermal event. It does this through detecting hydrocarbon gas levels — methane, propane, butane, hydrogen, methanol, ethanol, diesel fuel, gasoline — and warning about these gas levels before they reach their lower explosive limit (LEL).

The LEL is the smallest amount of the gas that supports a flame when mixed with oxygen and ignited. Zero percent (0%) LEL indicates a gas-free atmosphere. One hundred percent (100%) LEL indicates that the air concentration for that gas has reached its lower explosive limit.

The system consists of two external sensors and a control panel.

The sensors are located under the deck plates at the midpoint of the high-voltage batteries as shown in Fig. . This places them where rising gas vapors from the high-voltage batteries pass by or accumulate.

  1. Right-Hand Zone 2 Sensor

  2. Left-Hand Zone 1 Sensor

Fig. 1, Gas Detection System Sensors

Two labels on the control panel highlight important information about the combustible gas detection system. The combustible gas status label as shown in Fig. which serves as a reminder to what the warning light colors represent. The warning label as shown in Fig. which outlines what to do if the buzzer sounds and the lower red indicator illuminates.

The control panel is mounted in the front overhead panel of the cab as shown in Fig. .

Fig. 2, Combustible Gas Status Label

Fig. 3, Control Panel Warning Label

Warning: Immediately bring the vehicle to a safe stop when the buzzer alarm sounds and the lower red 'Significant' LED illuminates. Apply the park brake, turn off the ignition, and get clear of the vehicle.

If possible, hit the eStop button the dash prior to exiting the cab.

Move a safe distance from the vehicle, fifty to one hundred feet if possible, and upwind of any smoke. Call emergency services.

If possible, set out reflectors or flares to keep other people and vehicles at a safe distance and to guide them around the vehicle.

  1. Combustible Gas Status Label

  2. Warning Label

  3. Alarm Silence Switch

  4. Yellow Alarm Silence LED

  5. Piezo Buzzer

  6. Yellow System Reset LED

  7. System Reset Switch

  8. Test Switch

  9. Yellow Sensor Zone LED

  10. Yellow System Fault LED

  11. Green System Normal LED

  12. Yellow Trace Gas LED

  13. Red Significant Gas LED

Fig. 4, USA Pro Shoreline Multizone Detection System Control Module

Note:
Parent topic: Combustible Gas Detection System
Document Number: 0000088940
Manual Publication Date: 2024-03-21
Topic Publication Date: 2025-02-13