Overspeed

What does SOF mean?

The motor speed has exceeded its commanded or permissible limit, often due to an unstable control loop, an excessive regenerative load, or a mechanical runaway condition. This fault is critical as it can lead to mechanical damage to the driven equipment, create safety hazards, and result in a complete loss of control over the motor.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Add a braking resistor (and braking unit) if the application involves high inertial loads or frequent rapid decelerations that cause regenerative energy feedback.

2. 4

   Verify that the motor and drive are correctly sized for the application's torque and speed requirements.