Mitsubishi Electric MELSEC-Q00U(J)CPU User Manual page 269

(4) LED indication
The LEDs on the front of the CPU module indicate backup status.
Value stored in
Backup status
SD690
2
Backup start preparation completed
H
3
Backup in execution
H
4
Backup completed
H
FF
Backup error
H
LED indication
MODE: Flash (green), BAT.: Flash (green)
Indication status changes as follows at 800ms intervals.
1) MODE: Flash (green), BAT.: On (green)

2) MODE: Flash (green), BAT.: On (green), USER: On (red)

3) MODE: Flash (green), USER: On (red)
MODE: Flash (green), BAT.: Flash (green), BOOT: Flash (green)
MODE: Flash (green), USER.: Flash (red), BAT.: Flash (green)
CHAPTER 3 FUNCTIONS
267
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