Motor Overload (Electronic Thermal)

What does OL1 mean?

The electronic thermal overload function estimates motor temperature based on inverter output current and time. When this function is activated, an OL1 error occurs, shutting OFF the inverter output to prevent excessive motor overheating. Persistent overload significantly reduces motor lifespan and can cause winding insulation failure.

• Continuous motor current exceeding the motor's rated current (Parameter P1-03) for an extended period.
• Incorrect motor rated current (Parameter P1-03) or motor thermal constant (e.g., Parameter A1-02) set in the inverter.
• Mechanical binding or excessive friction in the driven equipment, increasing the required motor torque.
• Blocked or damaged motor cooling fan, leading to reduced motor heat dissipation.
• Inadequate motor sizing for the application, causing it to continuously operate in an overloaded state.

Click steps to track your progress.

1. 1

   1. Verify the motor's rated current (Parameter P1-03) and motor thermal time constant (e.g., A1-02) match the motor nameplate data exactly.

2. 2

   2. Measure the actual motor current using a clamp meter and compare it to the motor's Full Load Amperage (FLA) during operation.

3. 3

   3. Inspect the motor's external cooling fan and cooling fins for any blockages, damage, or excessive dirt accumulation.

4. 4

   4. Disconnect the motor from the load and manually rotate the shaft to check for any mechanical binding or excessive resistance in the driven equipment.

5. 5

   5. Adjust current limit parameters (e.g., Parameter C1-04) if the application permits brief overloads without damaging the motor.