Auto-tuning Resistance Fault

What does Er - 04 mean?

Auto-tuning did not complete within the specified time, or the tuning result for resistance fell outside the parameter set range. This can be caused by incorrect input data, motor wiring issues, or a connected mechanical load interfering with the tuning.

• Incorrect motor nameplate data (e.g., motor rated current P2-01, motor rated voltage P2-02) entered into the drive's parameters.
• High resistance or an open circuit in one or more motor phases due to loose connections at motor terminals or drive output terminals (U/T1, V/T2, W/T3).
• Motor stator winding damage (e.g., partial short or open circuit) increasing effective resistance beyond acceptable limits.
• Motor disconnected or not properly coupled to the load during the auto-tuning process, preventing accurate resistance measurement.
• Internal drive hardware fault in the current sensing or measurement circuit affecting resistance calculations.

Click steps to track your progress.

1. 1

   1. Verify all motor nameplate data (rated current, voltage, frequency, poles) against drive parameters (P2-01 to P2-04). Correct any discrepancies.

2. 2

   2. Disconnect motor from the drive. Measure resistance between motor output terminals U/T1-V/T2, V/T2-W/T3, W/T3-U/T1 with a multimeter. All three values should be balanced within 5%.

3. 3

   3. Inspect motor terminal block and drive output terminals (U/T1, V/T2, W/T3) for loose connections, corrosion, or signs of overheating. Tighten connections to manufacturer specifications.

4. 4

   4. Ensure the motor is connected to the drive and is stationary (not mechanically loaded or rotating) during the auto-tuning process (e.g., parameter H3-02 set to 1 or 2).

5. 5

   5. If fault persists, try running auto-tuning with a different, known-good motor (within drive kVA rating) to isolate the issue to either the drive or the motor.