378

Search the part program for G51 commands and identify the P scaling factor value specified.

Verify the P value is between 0.001 and 999.999 (or check your specific control's parameter manual for exact limits).

Correct any scaling factors that are zero, negative, or exceed maximum limits in the program.

Reset the alarm, return to program start, and test run the corrected program in single block mode.

Ensure G50 (scaling cancel) is programmed before the end of operations using G51 to avoid carrying scaling into subsequent programs.

Locate the G51 scaling command and verify that scaling center coordinates are properly specified (e.g., G51 X0 Y0 Z0 P1.5).

Confirm that all specified axes (X, Y, Z, etc.) exist on your machine configuration and are not axis names that are invalid for your control.

Check that incremental center point values using I, J, K (if used) are properly formatted and contain valid numerical data.

Correct the G51 command format according to Fanuc programming manual specifications and verify syntax matches control requirements.

Different Fanuc control series (0i, 16i, 31i, etc.) may have slightly different G51 format requirements. Consult your specific control manual.

Check parameter 5420 (or series-specific scaling parameters) to verify that scaling function is enabled (typically bit setting must allow G51).

Parameter changes require appropriate access level and may require control restart. Document original values before making changes.

Review parameters 5431-5433 for any axis-specific scaling prohibitions or restrictions that may prevent scaling on commanded axes.

Verify that scaling is not being commanded during canned cycles, compensation modes (G41/G42 active), or other operations prohibited by your control version.

If parameters were incorrect, correct them per machine requirements, cycle power on the control, and retest the program.

Always coordinate parameter changes with production management as they affect all programs run on the machine.