160-0142

Check NC Program Block Sequence

Review the NC program around the alarm occurrence for rapid successive auxiliary axis commands (M-functions, spindle positioning, or rotary axis moves) without proper dwell times.

Look specifically for M19 spindle orient followed immediately by rotary axis movement

Insert G4 Dwell Commands

Add G4 P0.1 (100ms dwell) or G4 P0.2 after auxiliary axis positioning commands to ensure completion before next command execution.

Excessive dwell times will increase cycle time - start with minimal values

Verify Auxiliary Axis Parameters

Check machine parameters MP7500-MP7599 (auxiliary axis configuration) to ensure proper axis type definition and feedback settings match the physical setup.

Test Program Execution

Run the modified program in single block mode to verify each auxiliary axis command completes before the next command executes.

Check Servo Drive Status LEDs

Verify all servo drive status indicators show normal operation (typically solid green) and no communication fault LEDs are active on the drive modules.

Ensure machine is in safe state before checking electrical panels

Verify Position Loop Parameters

Access Setup > Machine Parameters and check MP1020-MP1099 (position loop) for the affected auxiliary axis. Verify following error window and in-position tolerance settings.

Compare parameters with a working similar axis if available

Monitor Real-Time Position Values

Use Setup > Diagnosis > Position to monitor actual vs. nominal position values during auxiliary axis movement to identify positioning completion delays.

Check EnDat/Resolver Feedback

Verify encoder feedback system integrity through Setup > Diagnosis > Encoder and check for any feedback signal interruptions or noise.

Verify Axis Type Definition

Check MP100-MP199 (axis configuration) to ensure the auxiliary axis is properly defined as rotary, linear, or spindle type matching the physical axis.

Incorrect axis type can cause completion signal misinterpretation

Review Movement Monitoring Parameters

Examine MP1400-MP1499 (movement monitoring) for standstill monitoring and positioning window settings that may be too restrictive for the auxiliary axis.

Check Auxiliary Function Parameters

Verify MP7300-MP7399 (M-function configuration) if the auxiliary axis is controlled via M-functions, ensuring proper timing and completion signal assignment.

Compare with Backup Parameters

If available, compare current machine parameters with a known good backup using Setup > Machine Parameters > Load/Save functions.

Access PLC Program Monitor

Navigate to Setup > PLC > Program Run to monitor PLC execution and identify any auxiliary axis control markers (M-markers) that may be stuck or cycling incorrectly.

Only modify PLC program if you have proper authorization and backup

Check Auxiliary Axis PLC Markers

Monitor specific M-markers related to auxiliary axis positioning (typically M4xxx series) to verify proper state transitions during axis movement commands.

Review PLC Cycle Time

Check PLC cycle time in Setup > PLC > Diagnosis to ensure it's within acceptable limits (typically <10ms) for proper real-time auxiliary axis control.

Verify I/O Signal Timing

Use Setup > PLC > I/O Monitor to check physical input/output signals from auxiliary axis drives for proper timing and signal integrity.

Inspect Encoder Connections

Visually inspect all encoder cable connections at both the motor and drive ends for loose connections, damaged cables, or contamination.

Power down system before disconnecting any encoder cables

Check Encoder Signal Quality

Use Setup > Diagnosis > Encoder to monitor encoder signal amplitude and verify signals are within specification (typically 0.6-1.2V for EnDat systems).

Test Auxiliary Axis Movement

Manually jog the auxiliary axis using Setup > Manual Operation to verify smooth movement and proper position feedback throughout the full range of motion.

Verify Limit Switch Operation

Check auxiliary axis limit switches and reference point switches through Setup > PLC > I/O Monitor to ensure proper operation and signal states.