FANUC Technical Support & Troubleshooting Spindle Alarm Codes
FANUC Spindle Alarm Codes (AL-A through AL-20)
Alarm A (AL-A) ROM Abnormality
Cause: Incorrect ROM, ROM not installed correctly, error with control circuit.
Remedy: Install correct ROM, replace control circuit.
Alarm 01 (AL-01) Motor Overheat
Causes: Damaged motor fan, overload, motor cooler is dirty, loose connection.
Remedy: Replace parts, clean cooler, check connections, review cutting conditions.
Alarm 02 (AL-02) Excessive Speed Deviation
Causes: Overload, transistor module is damaged, loose connections, error with speed feedback signal, blown fuse.
Remedy: Replace parts, check connections, review cutting conditions.
Alarm 03 (AL-03) Blown Fuse in DC Link Section
Causes: Indicates that the fuse F4 in DC link is blown (models 30S and 40S).
Remedy: Check power transistors and replace fuse.
Alarm 04 (AL-04) Input fuse blown / Input power open phase
Causes: Defective transistor module, blown fuse.
Remedy: Replace parts, replace fuse.
Alarm 05 (AL-05) Control Power Supply Fuse Blown
Causes: Defective PCB, Abnormal power supply voltage.
Remedy: Check power supply, replace PCB, replace fuse.
Alarm 07 (AL-07) Excessive Speed
Causes: Incorrect parameter setting.
Remedy: Reset parameter value.
Alarm 08 (AL-08) High Input Voltage
Causes: AC power supply too high, incorrect setting of toggle switch for voltage setting.
Remedy: Change setting from 200V to 230V.
Alarm 09 (AL-09) Heat sink is overheated
Causes: Cooling fan is defective, overload, dust and dirty.
Remedy: Replace fan, review cutting conditions, clean parts.
Alarm 10 (AL-10) Input Power Voltage Low
Causes: Drop in input power, momentary power failure.
Remedy: Correct case and reset alarm.
Alarm 11 (AL-11) Overvoltage of DC Link Circuit
Causes: High power impedance, PCB or transistor module are defective.
Remedy: Check AC power, replace damaged parts.
Alarm 12 (AL-12) Overcurrent flows to DC Link Circuit
Causes: Output terminals or internal motor of motor is shorted, defective PCB or transistor module.
Remedy: Check connections, replace damaged parts.
Alarm 13 (AL-13) CPU Inter Data Memory Alarm
Cause: Defective PCB
Remedy: Replace PCB
Alarm 15 (AL-15)
Cause: Spindle switch /output switch alarm.
Remedy: Check sequence.
Alarm 16 (AL-16) RAM Abnormality
Causes: Defective RAM or PCB.
Remedy: Replace RAM, replace PCB.
Alarm 18 (AL-18) Program ROM sum check error
Causes: Defective ROM.
Remedy: Replace ROM.
Alarm 19 (AL-19)
Causes: Defective A/D convertor or PCB, loose connections.
Remedy: Replace A/D convertor, replace PCB, check connections.
Alarm 20 (AL-20)
Causes: Defective PCB, loose connections.
Remedy: Replace PCB, check connections.
FANUC Spindle Alarm Codes (AL-24 through AL-49)
Alarm 24 (AL-24)
Causes: CNC power off, defective optical cable.
Remedy: Turn power on, clean or replace optical cable, replace LSI, replace PCB.
Alarm 25 (AL-25)
Cause: See Alarm 24
Remedy: See Alarm 24
Alarm 26 (AL-26)
Cause: Defective signal level/line of spindle motor for C axis control, defective detector circuit for C axis control, incorrect parameter setting.
Remedy: Check signal level, connect signal cable securely, replace detector circuit, set correct parameter value.
Alarm 27 (AL-27)
Causes: Position coder signal line defective, incorrect parameter setting.
Remedy: Connect signal cable securely, replace signal cable, set correct parameter values.
Alarm 28 (AL-28)Cause: Defective signal level/line of spindle motor for C axis control, defective detector circuit for C axis control.
Remedy: Check signal level, connect signal cable securely, replace detector circuit.
Alarm 29 (AL-29)
Cause: Overload.
Remedy: Review cutting conditions.
Alarm 30 (AL-30)
Cause: Defective power transistor, defective PCB.
Remedy: Replace power transistor, replace PCB.
Alarm 31 (AL-31)
Cause: Motor constrained, defective motor speed reversion signal/signal cable
Remedy: Connect cable securely, replace cable.
Alarm 32 (AL-32)
Cause: Defective LSI.
Remedy: Replace LSI, replace PCB.
Alarm 33 (AL-33)
Cause: Defective relay, disconnected resistor.
Remedy: Replace amp.
Alarm 34 (AL-34)
Cause: Incorrect parameter setting
Remedy: Set correct parameter values.
Alarm 35 (AL-35)
Cause: Incorrect parameter setting for gear ratio and position gain data.
Remedy: Set correct parameter values.
Alarm 36 (AL-36)
Cause: Error count overflow
Remedy: Correct cause and reset the alarm.
Alarm 37 (AL-37)
Cause: Incorrect parameter setting (No.6511)
Remedy: Set correct parameter values.
Alarm 39 (AL-39)
Cause: Incorrect ROM version.
Remedy: Replace ROM version.
Alarm 40 (AL-40)
Cause: No occurrence of 1-rotation signal.
Remedy: Make 1-rotation signal offset adjustment, check cables.
Alarm 41 (AL-41)
Cause: Incorrect parameter setting (No. 6503), incorrect amplitude and offset of position coder feedback signal.
Remedy: Set correct parameter value, adjust feedback signal, check shielding status.
Alarm 42 (AL-42)
Cause: Position coder 1-rotation signal not detected.
Remedy: Make 1-rotation signal adjustment for signal conversion circuit.
Alarm 43 (AL-43)
Cause: Disconnection of position coder signal for differential speed mode.
Remedy: Check main spindle position coder signal is connected to connector CN12
Alarm 46 (AL-46)
Cause: Failure in detecting position coder 1-rotation signal in thread operation.
Remedy: Make 1-rotation signal adjustment for signal conversion circuit. Check cable shield status.
Alarm 47 (AL-47)
Cause: See Alarm 41
Remedy: See Alarm 41
Alarm 48 (AL-48)
Cause: The position coder 1-rotation speed is too high
Remedy: Make 1-rotation signal adjustment for signal conversion circuit
Alarm 49 (AL-49)
Cause: The converted differential speed is too high
Remedy: Calculate differential speed and check if this value is not greater than the maximum speed of the motor.
FANUC Spindle Alarm Codes (AL-50 through AL-55)
Alarm 50 (AL-50)
Cause: Excessive speed command calculation value in spindle synchronization control.
Remedy: Calculate motor speed and check if it is not greater than max motor speed
Alarm 51 (AL-51)
Cause: Undervoltage at DC link section.
Remedy: Correct cause and reset the alarm.
Alarm 52 (AL-52)
Cause: ITP signal abnormality I.
Remedy: Correct cause and reset the alarm.
Alarm 53 (AL-53)
Cause: ITP signal abnormality II.
Remedy: Correct cause and reset the alarm.
Alarm 54 (AL-54)
Cause: Overload current alarm
Remedy: Check if overload operation or frequent acceleration/deceleration is performed.
Alarm 55 (AL-55)
Cause: Power line abnormality in spindle switching/output switching.
Remedy: Check magnetic contractor for power line switching.
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