Vacon Vacon 100 Error Code 3

Vacon PLC & VFD Critical Motor

Model: Vacon 100 | Code: 3

Applicable Systems
Vacon 100

Symptoms

Ground fault. The drive has detected a ground fault on the motor output. Current is flowing to ground insteadof through the motor.

Possible Causes

  • Motor winding insulation failure to frame
  • Motor cable insulation damage causing ground fault
  • Water in motor junction box
  • Drive ground fault detection sensitivity too high

Troubleshooting Steps

  1. Step 1: Check the equipment status and fault indicators to confirm the active fault code
    Fault indicator or HMI displays code 3 as active
  2. Step 2: Verify all electrical connections, wiring harnesses, and connector seating
    All connections secure, no corrosion, loose pins, or damaged wires
  3. Step 3: Check motor cable connections at drive output terminals for correct phase sequence and tightness
    Cables securely connected, phase sequence correct, no loose terminals
  4. Step 4: Measure motor winding insulation resistance with a megger (500V DC minimum)
    Insulation resistance above minimum value (typically > 1 Megaohm)
  5. Step 5: Verify drive parameter settings match motor nameplate data (current, voltage, power, RPM)
    All motor nameplate parameters correctly entered in drive
  6. Step 6: Inspect motor for mechanical overload, bearing seizure, or driven equipment jam
    Motor rotates freely, no mechanical binding or excessive load
  7. Step 7: Reset the fault after fixing the root cause: clear the fault via HMI or power-cycle
    Fault clears and drive resumes normal operation without recurrence

How to Reset

To reset: 1) Identify and fix the root cause described in the fault symptoms. 2) Press RESET on the HMI or controller, or power-cycle the equipment. 3) If the fault recurs, contact manufacturer service. Caution: Document the fault code and context before resetting.

Frequently Asked Questions

  • Q: What does fault code 3 mean on the Vacon Vacon 100?

    Fault 3 on the Vacon Vacon 100 indicates: Ground fault. The drive has detected a ground fault on the motor output. Current is flowing to ground instead of through the motor. Refer to the equipment manual and manufacturer support for specific troubleshooting steps.

  • Q: Can I continue operating the equipment with fault 3 active?

    No. The equipment has detected a fault condition and has taken protective action (typically stopping or derating). Continuing to operate without fixing the root cause may cause further damage. Always investigate and fix the fault before resuming operation.

Related Vacon Fault Codes

Source: Vacon 100/100X Drive User Manual, Danfoss/Vacon Documentation

Category: PLC & VFD