Hardware Overcurrent

What does F12 mean?

This critical fault signifies that the instantaneous output current from the drive has surpassed a predefined hardware current limit, indicating a severe and immediate overcurrent condition. This can be caused by a short circuit in the motor or motor wiring, an extremely sudden and heavy mechanical load, incorrect motor parameters, or excessive DC braking. This fault is a protective measure to prevent damage to the drive's internal power devices. Unresolved, it poses a risk of catastrophic drive failure.

• Sudden short circuit in the motor wiring (U, V, W terminals) or inside the motor windings (phase-to-phase or phase-to-ground).
• Motor insulation breakdown causing a direct short to ground or between phases.
• Rapid mechanical shock or sudden jamming of the driven load causing an immediate and severe motor current spike.
• Internal component failure within the drive's power stage (e.g., IGBT module short circuit).
• Incorrect motor parameters (e.g., P2-01 to P2-08) or autotune failure leading to unstable motor control.

Click steps to track your progress.

1. 1

   Disconnect all motor leads (U, V, W) from the drive output terminals.

2. 2

   With the motor disconnected, power cycle the drive and attempt to run it without a load (e.g., to 10Hz). If the fault persists, the drive is faulty.

3. 3

   Measure the resistance between motor phases (U-V, V-W, W-U) and from each phase to ground (using an ohmmeter and megohmmeter) to check for shorts.

4. 4

   Inspect the motor cable for physical damage to its insulation or shielding that could cause phase-to-phase or phase-to-ground faults.

5. 5

   Ensure the acceleration time parameter (e.g., P1-09) is not set excessively short for the motor and load inertia.

6. 6

   Verify that all motor nameplate parameters (P2-01 to P2-08) are accurately entered into the drive.