61402

Review CYCLE977 call parameters in NC program: check the measurement position coordinates (typically SX, SY for plane axes) against actual workpiece geometry and clamping limits. Use the HMI Diagnostics > Actual Values menu to verify current soft-limit values.

Access SINUMERIK 840D soft-limit machine data via NCK > Axis Data > MD 36010 (min) and MD 36015 (max) for affected axes. Compare programmed probe position against these limits; if probe coordinate exceeds limits, the alarm is justified.

Modifying soft limits without machine geometry verification can cause physical collisions.

Recalculate or adjust CYCLE977 measurement position to remain within active software limits. Document the safe measurement envelope based on workpiece setup and re-test with a dry-run (single block, reduced feed).

Clear alarm via NC > Alarms menu after correcting coordinates. Monitor probe approach in next cycle execution; use DIN/CCW probe diagnostic display to confirm probe retracts safely.

Verify machine geometry and physical travel limits using manual JOG in NCK > Manual > Continuous jog mode. Record the actual min/max positions where the spindle/probe head can safely travel without mechanical obstruction.

Use low jog speed (F10-F50) when approaching limit positions to prevent crash.

Compare recorded physical limits against MD 36010 and MD 36015 values. Access via NCK > Machine Data > Axis Data, select affected axis, view MD 3600x range. Soft limits should typically be 5-10mm inboard of physical limits to provide safety margin.

If soft limits are incorrect, edit MD 36010 and MD 36015 to align with safe machine geometry. Document changes in machine logbook. Save and perform a controlled restart (NC Stop > Power On cycle) to activate new MD values.

Incorrect soft limits can allow real collisions; verify against machine documentation or OEM specifications.

Re-run CYCLE977 probe measurement in single-block mode to confirm alarm no longer fires. Use Trace (NCK > Diagnostics > Trace) to log actual vs. commanded positions.

Access Tool Offset Table via NCK > Tool Management > Tool Offset Table or HMI > Tools. Locate the probe tool (typically a measuring stylus) and review offset values (D offset = diameter/radius, Length offsets for probe extension). Compare against probe calibration certificate or last-known good values.

Verify probe calibration using a calibration block or gauge (per ISO 13225 or machine manual). Use CYCLE978 (Probe Offset Calibration) if available on your SINUMERIK version, or manual touch-off in NCK > Manual > Jog + Offset Setting. Record actual probe tip position.

If probe offsets are incorrect, update Tool Offset Table values to match calibration results. Re-run CYCLE977 test cycle and monitor DIN/CCW probe indicator and actual position feedback (NCK > Diagnostics > Actual Values > Probe Axis Position) to confirm probe approach stays within limits.