ALM LED Blink (3:1)
Power Failure (Subsequent Unit)
Fanuc · R-30iB Mate + Mate Plus Robot
What does ALM LED Blink (3:1) mean?
The red ALM LED blinks with a 3:1 duty cycle (1.5s ON / 0.5s OFF), indicating a power failure (which may include instantaneous power failure) in a unit subsequent to the unit of interest. This signifies a power supply interruption downstream from the current unit.
Common Causes
- A power failure or significant voltage fluctuation has occurred in the subsequent unit or module connected to the main system.
- The power supply to an external component has been interrupted, causing it to go offline.
- This could be due to an issue with the external unit's power supply, the wiring to it, or a main power disturbance.
- The control system has detected a loss of operational power in a connected device.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Identify and remove the cause of a power failure in a unit subsequent to the unit of interest.
Verified technical data. Last updated: March 2026
Related Faults
Source: Fanuc R-30iB Mate + Mate Plus Robot