Fanuc Alpha Power Supply Fault Codes
These codes and troubleshooting apply to DC and AC Fanuc power supplies that begin with part number A06B-6077, A06B-6081, and A06B-6087. On the LED display for these units, a “-” will mean that the power supply is not ready while a “0” means that the power supply is powered up correctly. If it reads something other than these two then the power supply has an alarm that needs to be corrected. Below is the list of Fanuc Alpha Power Supply fault codes.
AL-01: Overcurrent in the Main Power Module.
AL-02: Cooling Fan Stopped.
AL-03: The temperature of the main circuit heat sink has risen abnormally.
AL-04: The DC Voltage has dropped.
AL-05: The main Capacitor was not recharged within the specified time.
AL-06: The Input Power Supply is Abnormal.
AL-07: In the main circuit the DC Voltage is abnormally high
A common alarm on installation of a new alpha power supply is an AL-05.
If you have this alarm we recommend double-checking the bus bar connector at the top of the power supply to make sure it is fully connected. Be sufe to check out our article on FANUC Alpha Servo Troubleshooting as well as FANUC CNC parts.