Klipper Power Failure Recovery

• The Klipper power failure recovery feature refers to the ability to automatically restore Klipper's printing status after power is restored following a power outage.
• Except for the C5 mainboard, all other FLY motherboards need to be used together with the KPPM power failure module.
• Not suitable for models where the Z-axis position shifts after a power outage.

Configuration

Disable Power-off Shutdown

Note

• You need to disable power-off shutdown, otherwise power failure recovery cannot be used.
• Power failure recovery includes a function to automatically shut down after saving progress.
• Please ensure no other power sources are connected to the host computer, otherwise it will not boot.

• Enter the device's IP address in the browser address bar, for example: http://192.168.6.179

• Access the configuration page

  • Open the device IP address in the browser, for example: http://192.168.1.2/
  • In Fluidd, as shown on the left in the figure below, uncheck -> Hide hidden files and folders.
  • In Mainsail, as shown on the right in the figure below, check -> Show hidden files.
  • At this point, you can see the .flyos-config folder. Enter this folder to find the sys-config.conf file.
  • The sys-config.conf file is a symbolic link to the config.txt configuration file in the removable disk FlyOS-Conf.
  
  • Open the sys-config.conf file and locate the shutdown_pin_state and shutdown_pin= configurations.
  • Add a # before these configurations.
  • Then Save -> Close and restart the system.
  

plr.cfg Configuration File

Note

• Please check the corresponding product documentation for configuration details.

Description of [homing_override]

Attention

• If you are using [homing_override], do not arbitrarily set the homing position within [homing_override]. Any failure of power failure recovery caused by this will not be covered.
• Configuration instructions for [homing_override] are provided below.

• Description
  • [force_move]: Enables the force move function, allowing forced movement to specified positions.
  • [force_move] replaces the set_position_z functionality in [homing_override]. Failure to follow this configuration may result in failure of the power failure recovery.
  • The [homing_override] configuration below is designed to ensure proper Z-axis homing during power failure recovery.

[force_move]
enable_force_move: true

[homing_override]
axes: z
gcode:
    {% set max_x = printer.configfile.config["stepper_x"]["position_max"]|float %}
    {% set max_y = printer.configfile.config["stepper_y"]["position_max"]|float %}
    {% if 'z' not in printer.toolhead.homed_axes %}
        SET_KINEMATIC_POSITION Z=0
        G90
        G0 Z5 F600
    {% endif %}
    {% set home_all = 'X' not in params and 'Y' not in params and 'Z' not in params %}

    {% if home_all or 'X' in params %}
    G28 X
    {% endif %}

    {% if home_all or 'Y' in params %}
    G28 Y
    {% endif %}

    {% if home_all or 'Z' in params %}
    G0 X{max_x / 2} Y{max_y / 2}  F3600 
    G28 Z
    G1 Z10 F2000
    {% endif %}

• Description of Z-axis lifting
  • This configuration defines the action to be executed only when the Z-axis has not been homed. This configuration does not affect normal operation.

  {% if 'z' not in printer.toolhead.homed_axes %}
      SET_KINEMATIC_POSITION Z=0
      G90
      G0 Z5 F600
  {% endif %}

Testing

• Print any file, and during printing, click the Emergency Stop button to simulate a power outage.
• Click Firmware Restart again and wait until Klipper reconnects normally.
• If a pop-up prompt appears on the web interface or KlipperScreen, it indicates that the power failure recovery function is working properly.
• Further tests under real power failure conditions can be conducted afterward.