MOTOR OVERLOAD

What does OLF mean?

This fault is triggered by an excessive motor current or an incorrect [Cold stator resist.] (rSC) parameter value. If the motor is continuously overloaded or the thermal protection settings are wrong, it can lead to motor damage due to overheating. Prompt resolution is crucial to prevent premature motor failure.

• Motor drawing excessive current due to mechanical overload (e.g., jammed bearing, increased friction, material buildup in the driven load).
• Incorrect motor nominal current (Parameter P2-02) or motor nominal power (P2-01) set in drive parameters, leading to incorrect thermal model calculation.
• Motor cooling fan obstructed or motor fan not operating correctly, resulting in motor overheating at nominal load.
• Thermal protection settings (e.g., Motor thermal current P2-05, Motor thermal time constant P2-06) configured too low for the application.
• High ambient temperature around the motor, reducing its ability to dissipate heat effectively.

Click steps to track your progress.

1. 1

   1. Measure actual motor current (IA, IB, IC) using a clamp-on ammeter and compare to the motor's nameplate nominal current (FLA) and drive's output current (r1.2).

2. 2

   2. Verify drive parameters P2-01 (Motor nominal power), P2-02 (Motor nominal current), and P2-03 (Motor nominal voltage) against the motor nameplate data.

3. 3

   3. Mechanically inspect the driven load for any obstructions, seized components, or excessive friction that could cause the motor to draw high current.

4. 4

   4. Check the motor's cooling fan for proper rotation and ensure air passages on the motor casing are clear of dust and debris.

5. 5

   5. Monitor the motor's thermal state via the drive's internal thermal model parameter (e.g., r1.7, thermal state of motor) to confirm overload condition.

6. 6

   6. If using an external thermal sensor (PTC/KTY), measure resistance across terminals LI6/LI7 (or similar) to confirm sensor integrity and temperature reading.