FANUC codes
FANUCSystemIntermediate30-60 minutes

5218

Fanuc Alarm 5218 - ILLEGAL PARAMETER (INCL. COMP)

SYSTEM ALARM 5218

Fanuc alarm 5218: SYSTEM ALARM 5218. This alarm indicates a fault condition detected by the Fanuc control. Refer to the alarm number and name to identify the specific system or function involved.

Root Cause Summary

Fanuc alarm 5218 indicates an illegal parameter configuration related to inclination compensation functionality, typically on machines with rotary axes (A, B, C). This occurs when compensation parameters are inconsistent, out of range, or incompatible with the current machine configuration or control software version.

Causes and Fixes

  1. 1

    Navigate to SYSTEM > PARAM and search for parameter 19500 (inclination compensation enable). Verify bit settings match your machine's rotary axis configuration (typically bit 0=A-axis, bit 1=B-axis, bit 2=C-axis enable).

  2. 2

    Check parameters 19501-19510 for compensation axis assignment and direction codes. Valid values are typically 0-5 representing +/-X, +/-Y, +/-Z axes. Values outside this range trigger the alarm.

  3. 3

    Review parameters 19520-19599 containing compensation data tables. Each entry must be within machine travel limits and monotonically increasing. Use SYSTEM > PARAM > [SRCH] function to locate and verify each table entry.

  4. 4

    If parameters appear valid, perform a parameter backup, then reset inclination compensation parameters to default (set P19500 to 0, clear all data tables). Power cycle and re-enable compensation incrementally to isolate the problematic parameter.

    Disabling inclination compensation will affect machining accuracy on parts requiring rotary axis positioning. Notify production before making changes.

DIY Feasiblehigh confidence

Call a technician if:

  • ·Software option requires enabling
  • ·Parameter corruption persists after restoration
  • ·Machine geometry measurements needed

Prevention

  • Maintain current parameter backups
  • Monitor battery voltage regularly
  • Document inclination settings during installation
  • Verify software options before parameter changes

Common Mistakes

  • Setting inclination angles without measuring actual machine tilt
  • Enabling compensation without proper software option
  • Using incorrect parameter number ranges
  • Forgetting to power cycle after parameter changes

Related Alarms

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