Fanuc FANUC 0i Servo Alarm 411

Fanuc CNC Info Excess position error on X axis during move

Model: FANUC Series 0 / 0i / 30i | Code: 411

Applicable Systems
Series 0i Series 16/18/21 Alpha Beta

Symptoms

The position deviation value when the X axis moves exceeds the set value.

Possible Causes

  • Servo motor overload or mechanical binding
  • Servo amplifier fault or parameter error
  • Encoder or pulse coder disconnection
  • Power supply voltage abnormality

Troubleshooting Steps

  1. Step 1: Check the diagnostic display (DGNOS) for detailed servo error information
    Identify the specific servo error type and axis
  2. Step 2: Inspect the servo motor and mechanical components for binding or overload
    No mechanical binding; motor turns freely
  3. Step 3: Check the servo amplifier status LEDs and connections
    Amplifier shows normal status (green LED)
  4. Step 4: Verify servo parameters (motor series, rotation direction, feedback pulses)
    All servo parameters match the motor specification
  5. Step 5: If the error persists, replace the faulty component (amplifier, motor, or encoder)
    New component eliminates the alarm

How to Reset

To reset servo alarm 411: 1) Identify and resolve the root cause (mechanical, electrical, or parameter). 2) Press RESET on the CNC panel. 3) If alarm persists, power cycle the CNC and servo amplifier. 4) Re-perform reference point return. Caution: Do not repeatedly reset without fixing the root cause; this may damage the servo system.

Frequently Asked Questions

  • Q: What does 411 mean on Fanuc FANUC 0/0i/30i Series?

    The position deviation value when the X axis moves exceeds the set value.

  • Q: How do I fix 411 on Fanuc?

    Follow the troubleshooting steps: Check the diagnostic display (DGNOS) for detailed servo error information

Related Fanuc Fault Codes

Source: FANUC CNC System Alarm Manual (doc.eleok.com)

Category: CNC