#920 Back Cover Opened

Description

#920 indicates that the back cover was opened while a task was in progress, causing the task to be forcibly stopped.
For safety reasons, as the laser tube is located at the rear of the machine, the back cover must remain closed.
Issues such as weak magnetic force or a malfunctioning back cover sensor may cause this error.
Please follow the instructions below to identify the root cause of the problem.

Possible Causes

Step 1

• Ensure the back cover is fully pressed down and the screws are securely tightened.

Confirm your result and determine the next step:

Step 2

Check whether the back cover icon in Action mode is displayed as open or closed.

Confirm your result and determine the next step:

Step 3

For safety, please set the power to 0% to ensure that no laser pulses are generated during the testing process.

Confirm your result and determine the next step:

Step 4

There is a magnet on the back cover; please open the back cover and inspect it.

Confirm your result and determine the next step:

Step 5

This step will guide you to test if the back cover sensor is functioning correctly using two external magnets.

• Open the back cover to locate the sensor.

• The back cover sensor will have two red LED indicators that remain constantly lit.
  

   

• Bring two external magnets close to the two LED indicators. When a magnet is detected, the indicator should "brighten." When both LEDs detect magnets simultaneously, a door-closed signal will be sent to the system, and the icon on the panel will change accordingly.
  Note: LED detection is polarity-sensitive. Therefore, the same side of a magnet may not light up both LEDs; you may need to flip the magnet or approach from the other side of the LED.

  
   

• Click "Action" on the panel, wait for homing to complete, and then check the icon.

  

  

Confirm your result and determine the next step:

Step 6

Remove the sensor's connection cable and check the icon.
When the sensor is disconnected from the system (mainboard), the icon should remain in the "Open" state.

• Turn off the machine and unplug the connection cable.

• Turn on the machine, go to "Action," wait for homing to complete, and then check the icon.

  

  

Confirm your result and determine the next step:

Step 6.1

Reconnect the cable and test again using magnets.

• Turn off the machine, reconnect the cable, and then turn it on.

• Place two magnets on the sensor's LED indicators.
  The indicators should "brighten" when the sensor detects the magnets.
  
  
   

• Go to "Action," wait for homing to complete, and then check the icon.

  

  

Confirm your result and determine the next step: 

Step 7

Restore the machine to factory settings and test again using magnets.

• Restore the machine to factory settings.
  (Home Machine Next Page Factory Reset Yes)
  
   
• Place two magnets on the sensor's LED indicators.
  The indicators should "brighten" when the sensor detects the magnets.
  
  
   

• Go to "Action," wait for homing to complete, and then check the icon.

  

  

Confirm your result and determine the next step:

Step 8 

Check the sensor's position; it may be misaligned or have fallen off, preventing it from detecting the magnet.
Please check if the screws are tight and the sensor is installed correctly.

Confirm your result and determine the next step:

Step 8.1

Readjust the sensor position and securely tighten the two screws and nuts.

Step 9

Remove the magnets, close the back cover, and check the icon status.

• Remove the magnets from the sensor.
  

• Close the back cover and tighten the screws.
  
   

• When the back cover is closed, the door icon should be displayed as closed; when opened, the door icon should be displayed as open.

  

  

Confirm your result and determine the next step: