I²xt overload

What does OC6 mean?

This fault signifies a cumulative thermal overload condition based on the square of current and time, resulting from frequent and prolonged acceleration processes with motor overcurrent or permanent motor overload with Imotor > Irmotor. This can severely stress the motor and drive components.

• Continuous motor operation above its rated current (e.g., Imotor > 1.05 x C0203) for extended periods, leading to thermal buildup.
• Frequent and heavy acceleration/deceleration cycles that repeatedly push the motor current significantly above its nominal value.
• Motor cooling fan failure or obstructed ventilation preventing adequate heat dissipation from the motor windings.
• High ambient temperature (e.g., >40°C) surrounding the motor and drive, reducing their effective thermal capacity.
• Incorrect motor thermal model parameters in the drive (e.g., C0203, P1-54, P1-55) not accurately reflecting the motor's characteristics.

Click steps to track your progress.

1. 1

   Monitor the motor current (C0004) and motor temperature (C0005, if sensor connected) during operation to identify sustained overload conditions.

2. 2

   Reduce the mechanical load on the motor if possible, or consider upsizing the motor to match the application requirements.

3. 3

   Increase acceleration and deceleration ramp times (e.g., C0256, C0257) to lower peak currents during dynamic operations.

4. 4

   Inspect the motor's cooling fan for proper operation and ensure that air vents on both the motor and drive are clear of obstructions.

5. 5

   Verify that the motor rated current (C0203) is correctly entered into the drive and that any service factor settings (P1-54, P1-55) are appropriate for the motor.