Fanuc Series 16i, 18i, 21i Alarms, Error Codes

Fanuc Series 16i, 18i and 21i Alarms.

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These alarm codes relate to both Model A & B.  NB: * denotes model B additional alarms.

 

Background Edit Alarm

Alarm CodeTypeDescription of Alarms/ Faults
???BP/S alarmBP/S alarm occurs in the same number as the P/S alarm that occurs in ordinary program edit.
140BP/S alarmIt was attempted to select or delete in the background a program being selected in the foreground ( note)

Note: Alarm in background edit is displayed in the key input line of the background edit screen instead of the ordinary alarm screen and is resettable by any of the MDI key operation.

 

Absolute pulse coder (APC) alarm

Alarm CodeTypeDescription of Alarms/ Faults
300*nth axis origin returnManual reference position return is required for the nth-axis (n=1-8)
301*APC alarm: nth axis communicationnth axis (n=1-8) APC communication error. Failure in data transmission.
302*APC alarm: nth axis over timenth axis( n=1-8) APC overtime error. Failure in data transmission.
303*APC alarm: nth axis framingnth axis (n=1-8) APC framing error. Failure in Data transmission.
304*APC alarm: nth axis paritynth axis (n=1-8) APC parity error. Failure in Data transmission.
305*APC alarm:nth axis pulse errornth axis (n=1-8) APC pulse error alarm.
306*APC alarm: nth axis battery voltage 0nth axis (n=1-8) APC battery voltage has decreased to a low level so that the data cannot be held.
307*APC alarm: nth axis battery low 1nth axis (n=1-8) APC battery voltage reaches a level where the battery must be renewed.
308*APM alarm: nth-axis battery low 2nth axis (n=1-8) APC battery voltage has reached a level where the battery must be renewed ( including when the power is OFF).
309* APC ALARM: n AXIS ZRN IMPOSSIBLE Return to the origin has been attempted without first rotating the motor one or more times.

 

Serial Pulse Coder ( SPC) alarms

 

Alarm CodeTypeDescription of Alarms/ Faults
360 n-AXIS: ABNORMAL CHECKSUM (INT)A checksum error occured in the built in pulse coder.
361 n-AXIS: ABNORMAL PHASE DATA (INT)A phase data error occured in the built in pulse coder.
362 n-AXIS: ABNORMAL REV.DATA (INT)A rotation speed count error occured in the built in pulse coder.
363 n-AXIS: ABNORMAL CLOCK (INT)A clock error occured in the built in pulse coder.
364 n-AXIS: SOFT PHASE ALARM(INT)The digital servo software detected invalid data in the built in pulse coder.
365 n-AXIS: BROKEN LED (INT)An LED error occured in the built in pulse coder.

 

366

 

 n-AXIS: PULSE MISS (INT)A pulse error occured in the built in pulse coder.
367 n-AXIS: COUNT MISS (INT)A count error occured in the built in pulse coder.
368 n-AXIS: SERIAL DATA ERROR (INT)Communication data from the built in pulse coder cannot be received.
369 n-AXIS: DATA TRANS; ERROR (INT)A CRC or stop bit error occured in the communication data being received from the built in pulse coder.
380 n-AXIS: BROKEN LED (EXT)The seperate detector is erroneous.
381 n-AXIS: ABNORMAL PHASE (EXT)A phase data error occured in the seperate linear scale.
382 n-AXIS: COUNT MISS (EXT)A pulse error occured in the seperate detector.
383 n-AXIS: PULSE MISS (EXT)A count error occured in the seperate detector.
384 n-AXIS: SOFT PHASE ALARM(EXT)The digital servo software detected invalid data in the seperate detector.
385 n-AXIS: SERIAL DATA ERROR (EXT)Communication data from the seperate detector cannot be received.
386 n-AXIS: DATA TRANS. ERROR(EXT)A CRC or stop bit error occured in the communication data being received from the seperate detector.
387*  n-AXIS: ABNORMAL ENCODER ( EXT)An error occurs in the seperate detector.

Servo Alarms

Alarm CodeTypeDescription of Alarms/ Faults
401SERVO ALARM: n-TH AXIS VRDY OFFThe n-th axis (axis 1-8) servo amplifier READY signal (DRDY) went off.
402SERVO ALARM: SV CARD NOT EXISTThe axis control card is not provided.
403SERVO ALARM: CARD/SOFT MISMATCHThe combination of the axis control card and servo software is illegal.
404SERVO ALARM: n-TH AXIS VRDY ONEven though the n-th axis ( axis 1-8) READY signal (MCON) went off the servo amplifier READY signal (DRDY) is still on. Or when the power was turned on, DRDY went on even though MCON was off.
405SERVO ALARM: (ZERO POINT RETURN FAULT)Position control system fault. Due to an NC or servo system fault in the reference positon return, there is a possibility that the reference position return could not be executed properly.
407SERVO ALARM: EXCESS ERRORThe difference in synchronous axis position deviation exceeded the set value.
409SERVO ALARM: n XIS TORQUE ALARMAbnormal servo motor load has been detected. Alternatively, abnormal spindle motor load has been detected in Cs mode.
410SERVO ALARM: n-TH AXIS-EXCESS ERRORThe position deviation value when the n-th axis ( axis 1-8) stops is larger than the set value.
411SERVO ALARM: n-TH AXIS- EXCESS OVERFLOWThe position deviation value when the n-th axis ( axis 1-8) moves is larger than the set value.
413SERVO ALARM: n-th AXIS- LSI OVERFLOWThe contents of  error register for the n-th axis ( axis 1-8) exceeded    power.
415SERVO ALARM: n-AXIS: EXCESS SHIFTA speed higher than 524288000 units/s was attempted to be set in the n-th axis (axis 1-8).
417SERVO ALARM: n-AXIS: PARAMETER INCORECTThis alarm occurs when the n-th axis is in one of the below states: (digital servo system alarm).

  1. The value set in Parameter NO. 2020( motor form) is out of teh specified limit.
  2. A proper value (111 or -111) is not set in parameter No. 2022 (motor revolution direction).
  3. Illegal data (a value below 0, etc) was set in parameter No. 2023 (number of position feedback pulses per motor revolution).
  4. Illegal data ( a value below 0 etc) was set in parameter No. 2024 (number of position feedback pulses per motor revolution).
  5. Parameters No. 2084 and No. 2085 ( flexible field gear rate) have not been set.
  6. A value outside the limit of {1 to the number of control axes) or a non continuous value ( Parameter 1023 ( servo  axis number) contains a value out of the range from 1 to the number of axes, or an isolated value ( for example 4, not preceded by 3). was set in parameter No 1023 ( servo axis number).
420SERVO ALARM: n-AXIS: SYNC TORQUE( M axis)During simple synchronous control, the difference between the torque commands for the master and slave axes exceeded the value set in parameter no 2078 and2079.
421SERVO ALARM: n-AXIS: EXCESSer (D)The difference between the errors in the semi closed loop and closed loop has become excessive during the dual position feedback.
422SERVO ALARM: n-AXISIn torque control of PMC axis control, a specified allowable speed has been executed.
423SERVO ALARM: n-AXISIn torque control of PMC axis control, the parameter set allowable cumulative travel distance has been executed.
430n AXIS: SV.MOTOR OVERHEATA servo motor overheat occured.
431n AXIS: CNV. OVERLOAD1. PSM : Overheat occured.

2. Beta series SVU: Overhead occured.

432n AXIS: CNV.LOWVOLT CON./POWFAULT1. PSM: Phase missing occured in the input voltage

2. PMSR: The control power supply voltage has dropped.

3. Alpha Series SVU: The control power supply voltage has dropped.

433n AXIS: CNV: LOW VOLT DC LINK
  1. PSM: The DC link voltage has dropped.
  2. PSMR: The DC link voltage has dropped.
  3. Alpha series SVU: The DC link voltage has dropped.
  4. Beta series SVU: The DC link voltage has dropped.
434n AXIS: INV. LOW VOLT CONTROLSVM: The control power supply voltage has dropped.
435n AXIS: INV. LOW VOLT DC LINKSVM: The DC Link Voltage has dropped.
436n AXIS: SOFTTHERMAL (OVC)The digital servo software detected the soft thermal state (OVC).
437n AXIS: OVERCURRENT POWERPSM: Overcurrent flowed into the input circuit.
438n AXIS: INV: ABNORMAL CURRENT1. SVM: The motor current is too high

2. Alpha series: The motor current is too high.

3. Beta series. The motor current is too high.

439n AXIS:CNV. OVERVOLT POWER1. PSM: The DC voltage is too high.

2. PSMR: The DC voltage is too high.

3. Alpha series SVU: The C link voltage is too high.

4. Beta serie SVU: The link voltage is too high.

440n AXIS:CNV. EX DECELERATION POW.1. PSMR: The regeneration discharge amount is too large.

2. Alpha series SVU: The regeneration discharge amount is too large. Alternatively, the regeneration discharge ciruit is abnormal.

 

441n AXIS: ABNORMAL CURRENT OFFSETThe digital servo software detected an abnormality in the motor current detection circuit.
442n AXIS: CNV. CHARGE FAULT/INV DB1. PSM. The spare discharge circuit of the DC link is abnormal.

2. PSMR: The spare discharge circuit of the DC link is abnormal.

3. Alpha series SVU: The dynamic brake cicruit is abnormal.

443n AXIS: COOLING FAN FAILURE1. PSM: The internal stirring fan failed.

2. PSMR: The internal stirring fan failed.

3. Beta series SVU: The internal stirring fan failed.

444n AXIS: COOLING FAN FAILURESVM: The internal stirring fan failed.
445n AXIS: SOFT DISCONNECT ALARMThe digital servo software detected a broken wire in the pulse coder.
446n AXIS: HARD DISCONNECT ALARMA broken wire in the built in pulse coder was detected by hardware.
447n AXIS: HARD DISCONNECT (EXT)A broken wire in the seperate detector was detected by hardware.
448n AXIS: UNMATCHED FEEDBACK ALARMThe sign of feedback data from the built in pulse coder differs from that of a feedback data from the seperate detector.
449n AXIS: INV. IPM ALARM1. SVM: IPM ( intelligent power module) detected an alarm.

2. Alpha series SVU: IPM ( intelligent power module) detected an alarm.

453*n AXIS: SPC SOFT DISCONNECT ALARMSoftware disconnection alarm of the a pulse coder.
460n AXIS: FSSB DISCONNECTFSSB communication was disconnected suddenly. The possible causes are as follows:

1. The FSSB communication cable was disconnected or broken.

2. The power to the amplifier was turned off suddenly.

3. A low voltage alarm was issued by the amplifier.

461n AXIS: ILLEGAL AMP INTERFACEThe axes of the 2- axis amplifier were assigned to the fast type interface.
462n AXIS: SEND CNC DATA FAILEDBecause of an FSSB communication error, a slave could not receive correct data.
463n AXIS: SEND SLAVE DATA FAILEDBecause of an FSSB communication error, the servo system could not receive correct data.
464n AXIS: WRITE ID DATA FAILEDAn attempt was made to write maintenance informatio on the amplifier maintenance screen but it failed.
465n AXIS: READ ID DATA FAILEDAt power up, amplifier initial ID information could not be read.
466n AXIS: MOTOR/AMP COMBINATIONThe maximum current rating for the amplifer does not match that for the motor.
467n AXIS: ILLEGAL SETTING OF AXISThe servo function for the following has not been enabled when an axis occupying a single DSP ( corresponding to two ordinary axes) is specified on the axis setting screen.

  1. Learning control (bit 5 of parameter NO. 2008=1)
  2. High speed current loop (bit 0 of parameter NO.2004=1)
  3. High speed interface axis (bit 4 of parameter NO. 2005=1)

 

Over Travel Alarms

Alarm CodeTypeDescription of Fault/Error
500OVER TRAVELExceeded the n-th axis (axis 1-8) + side stored stroke check I.
501OVER TRAVELExceeded the n-th axis (axis 1-8) – side stored stroke check I.
502OVER TRAVELExceeded the n-th axis (axis 1-8) +side stored stroke check II.
503OVER TRAVELExceeded the n-th axis (axis 1-8) – side stored stroke check II.
504OVER TRAVELExceeded the n-th axis (axis 1-8) +side stored stroke check III
505OVER TRAVELExceeded the n-th axis (axis 1-8) – side stored stroke check III
506OVER TRAVELExceeded the n-th axis (axis 1-8) + side hardware OT.
507OVER TRAVELExceeded the n-th axis (axis 1-8) – side hardware OT.
508INTERFERENCEA tool moving in the positive direction along the n axis has fouled another tool post.
509INTERFERNECEA tool moving in the negative direction along the n axis has fouled another tool post.
510OVER TRAVELAlarm for stroke check prior to movement. The end point specified in a block falls within the forbidden area defined with the stroke check in the positive direction along the N axis.
511OVER TRAVELAlarm for stroke check prior to movement. The end point specified in a block falls within the forbidden area defined with the stroke check in the negative direction along the N axis.

 

Overheat Alarms

Alarm CodeTypeDescription of Fault/Error
700OVERHEAT: CONTROL UNITControl unit overheat.
701OVERHEAT: FAN MOTORThe fan motor on top of the cabinet for the control unit is overheated.
704OVERHEAT: SPINDLESpindle overheat in the spindle fluctuation detection .

 

Rigid Tapping Alarms

Alarm CodeTypeDescription of Fault/Error
740RIGID TAP ALARM: EXCESS ERRORThe positional deviation of the stopped spindle has exceeded the set value during rigid tapping.
741RIGID TAP ALARM: EXCESS ERRORThe positional deviation of the moving spindle has exceeded the set value during rigid tapping.
742RIGID TAP ALARM: LSI OVERFLOWAn LSI overflow has occurred for the spindle during rigid tapping.

 

Serial Spindle Alarms

Alarm CodeTypeDescription of Fault/Error
749S-SPINDLE LSI ERRORIt is serial communication error while system is executing after power supply is on.
750SPINDLE SERIAL LINK START FAULTThis alarm is generated when the spindle control unit is not ready for starting correctly when the power is turned on in the system with the serial spindle.
752FIRST SPINDLE MODE CHANGE FAULTThis alarm is generated if the system does not properly terminate a mode change. The modes include the Cs contouring, spindle positioning, rigid tapping and spindle control modes.
754SPINDLE-1 ABNORMAL TORQUEAbnormal first motor load has been detected
762SECOND SPINDLE MODE CHANGE FAULTRefer to alarm No 752 for the 2nd axis
764SPINDLE-2 ABNORMAL TORQUESame as alarm number 754 for the second spindle
772SPINDLE-3 MODE CHANGE ERRORSame as alarm number 752 for the third spindle
774SPINDLE 3 ABNORMAL TORQUE ALARMSame as alarm number 754 for the third spindle
782SPINDLE 4 MODE CHANGE ERRORSame as alarm number 752 for the fourth spindle
784SPINDLE 4 ABNORMAL TORQUE ALARMSame as alarm number 754 for the fourth spindle

 

System Alarms * ( Model B )

Alarm CodeTypeDescription of Fault/Error
900ROM PARITYA parity error ocured in the CNC, macro, or servo ROM.
910SRAM PARITY: (BYTE 0 )A RAM parity error occured in the part program storage RAM.
911SRAM PARITY: (BYTE 1 )A RAM parity error occured in the part program storage RAM.
912DRAM PARITY: (BYTE 0 )A RAM parity error occured in the DRAM module.
913DRAM PARITY: (BYTE 1 )A RAM parity error occured in the DRAM module.
914DRAM PARITY: (BYTE 2 )A RAM parity error occured in the DRAM module.
915DRAM PARITY: (BYTE 3 )A RAM parity error occured in the DRAM module.
916DRAM PARITY: (BYTE 4 )A RAM parity error occured in the DRAM module.
917DRAM PARITY: (BYTE 5 )A RAM parity error occured in the DRAM module.
918DRAM PARITY: (BYTE 6 )A RAM parity error occured in the DRAM module.
919DRAM PARITY: (BYTE 7 )A RAM parity error occured in the DRAM module.
920SERVO ALARM ( 1-4 AXIS )Servo alarm ( 1st to 4th axis). A watchdog alarm condition occured, or a RAM parity error occured in the axis control card.
921SERVO ALARM ( 5-8 AXIS )Servo alarm ( 5th to 8th axis). A watchdog alarm condition occured, or a RAM parity error occured in the axis control card.
926FSSB ALARMFSSB alarm.
930CPU INTERRUPTCPU error (abnormal interrupt).
935SRAM ECC ERRORAn error occured in RAM for part program storage.
950PMC SYSTEM ALARM

PCxxx YYYYYYYYYYYY

An error occured in the PMC.
951PMC WATCH DOG ALARMAn error occured in the PMC.
970NMI OCCURED IN PMCLSIWith the PMC-SA1, an error occured in the PMC control LSI device on the motherboard ( I/O RAM parity).
971NMI OCCURED IN SLCWith the PMC-SA1, an I/O Link disconnection was detected.
972NMI OCCURED IN OTHER MODULEAn NMI occured on a board other than the motherboard.
973NON MASK INTERRUPTAn NMI occured as a result of an unknown cause.
974F-BUS ERRORA bus error occured on the Fanuc Bus.
975BUS ERRORA bus error occure don the motherboard.
976L-BUS ERRORA bus error occured on the local bus.