Overcurrent

What does OC5 mean?

An overcurrent condition (OC5) can be activated if motor phases are reversed, causing the motor's rotating field to mismatch the feedback system's. This leads to the motor drawing high current, potentially up to Imax (C0022), especially with V/f or vector control.

• Motor phase reversal (U, V, W) during installation, causing the motor's physical rotation to oppose the drive's commanded field direction.
• Incorrect motor feedback wiring (e.g., encoder A, B, Z, or Hall sensors) resulting in an inverted speed or position signal.
• Encoder fault providing intermittent or incorrect feedback, leading to the drive attempting to compensate with excessive current.
• Motor parameter P2-01 (Motor Direction) set incorrectly for the physical motor wiring and application requirements.
• Sudden, heavy mechanical load applied to the motor shaft, causing an immediate high current demand beyond drive capacity.

Click steps to track your progress.

1. 1

   1. Power down the drive, swap two motor output phases (e.g., U and V) at drive terminals T1 and T2, then re-power and test.

2. 2

   2. Verify motor encoder wiring for correct polarity and phase sequence at terminals X10 or X11 according to the drive manual.

3. 3

   3. Check the motor parameter P2-01 (Motor Direction) in the drive configuration; set to 0 (standard) or 1 (reversed) if necessary.

4. 4

   4. Disconnect the motor from the mechanical load and run it without load to confirm current draw (P0-04) is within limits.

5. 5

   5. Measure the resistance of each motor phase winding (U-V, V-W, W-U) at the motor terminals using an ohmmeter to detect shorts or opens.