Battery zero alarm
Battery Zero Alarm
Fanuc · Alpha i Series AC Servo Motor and Spindle
What does Battery zero alarm mean?
This alarm indicates that the absolute position data for the Pulsecoder may be lost or displaced, often occurring if the sensor head is moved after the initial power-on and conduction state, or if the battery is depleted/disconnected.
Common Causes
- Battery voltage has dropped to zero or critically low levels.
- Complete loss of battery power due to internal failure or disconnection.
- Faulty battery management system reporting incorrect voltage.
- Charger failure leading to complete battery discharge.
- Incorrect battery type or capacity selected in system configuration.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Detach cable K1 from connector OUT1 of the sensor circuit.
- 2
Connect connector IN2 to connector OUT1 on the sensor circuit.
- 3
Maintain this connection for 10 seconds.
- 4
Connect all other sensor cables correctly.
- 5
Reconnect cable K1 to OUT1.
- 6
Perform reference position return operation after ensuring the alarm is issued.
Verified technical data. Last updated: March 2026
Related Faults
Source: Fanuc Alpha i Series AC Servo Motor and Spindle