Speed monitoring

What does F-08 mean?

The inverter's current controller is working at its set limit due to conditions like mechanical overload, phase failure in the mains or motor, or exceeding the maximum speed for VFC operating modes. This fault indicates the drive is struggling to maintain its commanded speed or torque. Unresolved, it can lead to motor and inverter overheating.

• Mechanical overload on the motor shaft exceeding the motor's rated torque, causing the inverter's current controller to hit its limit.
• Obstruction or excessive friction in the mechanical system driven by the motor (e.g., jammed conveyor, worn bearings, seized gearbox).
• Motor phase failure (open circuit) or short circuit between motor phases, causing current imbalance and controller limit triggering.
• Inverter current limit parameter (e.g., P1-06, P0-45) set too low compared to the actual motor load requirements.
• Exceeding the motor's maximum rated speed or the inverter's flux control limits in VFC (Voltage/Frequency Control) mode.

Click steps to track your progress.

1. 1

   Measure the motor current on each phase (U, V, W) during operation to detect imbalance or excessive current draw using a clamp meter.

2. 2

   Inspect the mechanical load for binding, seizing, or foreign material that could cause excessive friction or a jam.

3. 3

   Increase the inverter's current limit parameter (e.g., P1-06) to match the motor's full load current (FLA) plus a safety margin (e.g., 120-150% FLA).

4. 4

   Disconnect the motor and measure the resistance between motor phases (U-V, V-W, W-U) to confirm winding integrity and identify open circuits.

5. 5

   Verify the maximum output frequency parameter (e.g., P0-10) and ensure the motor's maximum operating speed (RPM) is not exceeded by the application.