Klipper Power Loss Resume Function

• The Klipper power loss resume function refers to the ability of Klipper to automatically restore its printing status after power is restored following a power outage.
• C5 can use this feature without requiring KPPM
• Not applicable for printers where the Z-axis will move after a power outage.

Configuration

Turn off power-off shutdown

Note

• Power-off shutdown needs to be turned off, otherwise the power failure resume function cannot be used.
• The power failure resume has a function to automatically shut down after saving the progress.
• Please ensure that there is no other power connected to the host, otherwise it will not be able to start up

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

• Enter 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 picture, uncheck -> filter hidden files and folders.
  • In mainsail, as shown on the right in the picture, check -> show hidden files.
  • At this point, you can see the .flyos-config folder, entering this folder will have the sys-config.conf file.
  • The sys-config.conf file is a soft link of the configuration file config.txt in the removable disk FlyOS-Conf.
  
  • Open the sys-config.conf file, find the configurations shutdown_pin_state and shutdown_pin=
  • Add a # before these configurations
  • Then save -> close and restart
  

plr.cfg configuration file

Note

• Replace the following in the configuration file: (PINS)
• with !host:gpiochip0/gpio260

• In the printer configuration page, find the plr.cfg file.
• Empty its content and paste the configuration below
• The configuration file content is as follows:

[mcu host]   
serial: /tmp/klipper_host_mcu

[power_loss_resume]
power_pin: (PINS)
is_shutdown: True # Whether to perform shutdown operation, enabled by default
paused_recover_z: -2.0 # Z movement distance when resuming printing if paused at power loss, default is no movement
start_gcode:
    # Gcode to execute before resuming printing
    # All parameters saved before power loss can be obtained through {PLR}
    # Use M118 {PLR} to output all available parameters
    M118 Resuming print: {PLR.print_stats.filename}
    M118 Interruption position: X:[{PLR.POS_X}] Y:[{PLR.POS_Y}] Z:[{PLR.POS_Z}] E:[{PLR.POS_E}]
    M140 S{PLR.bed.target}      ; Set bed temperature
    M104 S{PLR.extruder.target-10}  ; Set extruder temperature
    M109 S{PLR.extruder.target-10}  ; Wait for extruder to heat to set temperature
    G91                             ; Relative coordinates
    G1 Z2 F100                      ; Lift Z, prepare to home X,Y
    G90                             ; Absolute coordinates
    G28 X Y                         ; Home X Y
    M140 S{PLR.bed.target}          ; Set bed temperature
    M104 S{PLR.extruder.target}     ; Set extruder temperature
    M190 S{PLR.bed.target}          ; Wait for bed to heat to set temperature
    M109 S{PLR.extruder.target}     ; Wait for extruder to heat to set temperature
    M83                             ; Relative extrusion
    # G1 E0.5 F400                  ; Extrude a little
layer_count: 2 # Execute layer_change_gcode after resuming for specified layers
layer_change_gcode:                
    # Gcode to execute after resuming {layer_count} layers
    M118 Resume print speed
    M106 S{PLR.fan_speed}             ; Turn on cooling fan
    M220 S{PLR.move_speed_percent}    ; Set requested speed percentage
    M221 S{PLR.extrude_speed_percent} ; Set requested extrusion speed percentage
shutdown_gcode:
    # Gcode to execute before shutdown
    M118 Low power voltage, shutting down
    # M112 ; Emergency stop

Note

• The start_gcode macro in the above configuration file may need to be modified, specific modifications should be based on the actual machine.
• Note that if [homing_override] is used, do not随意 set the homing position in [homing_override]. If the power failure resume fails, we are not responsible.
• Note that if [gcode_macro _CLIENT_VARIABLE] is used, find variable_custom_park_dz and set it to 0

• After saving the configuration file above

• Open the printer.cfg file, and add the following content at the beginning of the file:

  
  [include plr.cfg]
  

• Click save and restart in the top right corner.

• At this point, the Klipper power failure resume function has been configured.

Test

• Print any file, click the Emergency Stop button during printing to simulate a power failure.
• Click Firmware Restart again, wait for Klipper to connect normally.
• If a pop-up appears on the web page or KlipperScreen, it means the power failure resume function is working properly.
• Subsequent tests can be done with real power outages.