KUKA KRC4 Error Code 125

KUKA Robot Major Motor

Model: KRC4 | Code: 125

Applicable Systems
KR CYBERTECH

Symptoms

Motor overcurrent. The motor current has exceeded the drive's maximum limit. The drive immediately disablesthe motor output.

Possible Causes

  • Motor phase-to-phase short circuit
  • Motor phase-to-ground short circuit
  • Drive output IGBT module failure
  • Excessive load or collision causing current spike

Troubleshooting Steps

  1. Step 1: Check the equipment status and fault indicators to confirm the active fault code
    Fault indicator or HMI displays code 125 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 125 mean on the KUKA KRC4?

    Fault 125 on the KUKA KRC4 indicates: Motor overcurrent. The motor current has exceeded the drive's maximum limit. The drive immediately disables the motor output. Refer to the equipment manual and manufacturer support for specific troubleshooting steps.

  • Q: Can I continue operating the equipment with fault 125 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 KUKA Fault Codes

Source: KUKA Robot Controller KRC4 Operating Manual, KUKA Roboter GmbH Documentation

Category: Robot