Over current fault

What does F1 mean?

The drive has detected an abnormally high current in one of the output phases, exceeding a hardware trip limit of 4 times the nominal current (Ih). This indicates an immediate and severe electrical overload condition. If left unresolved, it can lead to component damage or system instability.

• Motor phase-to-phase short circuit or phase-to-ground short circuit (e.g., due to insulation breakdown in motor windings).
• Excessive mechanical load on the motor shaft, causing the motor to draw current beyond its nominal rating (check load profile, gear wear).
• Drive output short-circuited to ground (e.g., through motor cable damage or terminal box contamination).
• Incorrect motor parameters (e.g., Parameter P1-50, P1-51) entered into the drive, causing inaccurate current control.
• Inverter power component (IGBT) failure or gate drive circuit issue within the drive.

Click steps to track your progress.

1. 1

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

2. 2

   Measure the resistance between each motor phase (U-V, V-W, W-U) and from each phase to ground using a megohmmeter (insulation tester). Compare to motor specifications (e.g., >1 Mohm).

3. 3

   If motor resistance is normal, reconnect the motor and verify motor load is within mechanical specifications using a torque wrench or load cell. Check for mechanical binding or overload.

4. 4

   Verify drive motor parameters (e.g., P1-50 'Motor nominal current', P1-51 'Motor nominal speed', P1-54 'Motor rated torque') match the motor nameplate data.

5. 5

   With the motor disconnected, perform a static self-test or low-voltage output test if available in the drive diagnostics menu (e.g., Menu 15-XX). Observe output current on display.

6. 6

   Check for any external short circuits in the motor cabling between the drive and the motor using a multimeter (ohmmeter) on all three phases.