How to troubleshoot a “primary fold too long detected” or “sensor crossfold too long detected" error message

How to troubleshoot a “primary fold too long detected” or “sensor crossfold too long detected" error message

This article covers the recommended steps to troubleshooting for the error message “primary fold too long detected” or “sensor crossfold too long detected.” 


🔧 Tools you may need:  Set of metric Allen wrenches


 Ⓘ NOTICE  Only qualified personnel familiar with the construction and operation of this equipment and the hazards involved should install, adjust, operate, and/or service this machine. Read and understand the manual in its entirety before proceeding. Failure to observe this precaution could result in severe bodily injury or loss of life. By proceeding, you are indicating that you acknowledge and agree that Foltex USA is not responsible for any damage to property or persons while accessing and/or using this service.


SENSOR PRIMARY FOLD TOO LONG DETECTED: This error is caused when the primary fold sensor is activated for too long. 


SENSOR CROSSFOLD TOO LONG DETECTED: This error is caused when the crossfold sensor is activated for too long. 


Clear items or belts activating sensor. 

  1. Activate the Jog Button to clear all pieces from the machine. 


Check ski alignment.

🗈 Misaligned skis can cause the crossfold entry sensor to trigger. 

  1. Activate the primary fold conveyor by starting the machine.

  2. Check that skis are parallel to each other.

  3. If needed, gently straighten the misaligned ski using small incremental motions. 


Check reflective sensors.

  1. Bring skis to the minimum width position using the HMI output screen. 

  2. Navigate to the input screen.

  3. If the Entry Sensor Primary Fold input is lit, then proceed to the section titled Troubleshoot Reflective Sensor.  

  4. If the Sensor Crossfold input is lit, then proceed to the section titled Troubleshoot Reflective Sensor

  5. Place an item under the primary entry sensor. If the Entry Sensor Primary Fold input is not lit, then proceed to the section titled Troubleshoot Reflective Sensor.

  6. Place an item under the crossfold entry sensor. If the Sensor Crossfold input is not lit, then proceed to the section titled Troubleshoot Reflective Sensor


Troubleshoot reflective sensor. 

  1. Verify that the sensor and reflector are clean and free of lint. 

  2. Verify the connection of the sensor cable is secure.

  3. Verify that each primary belt is under its guide and none are covering a reflector.  

  4. Verify the sensor is set to the correct sensitivity.

  5. Verify that the skis are not too close to one another. If so the skis may be blocking light going from sensor to reflector and back. If skis are not blocking the sensor, refer to the knowledge base article titled, “How to Troubleshoot the Minimum Width Sensor.”

  6. If the problem persists, then replace the sensor.



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