Motor Locked Rotor

What does Locked Rotor mean?

This fault occurs when the motor's rotor is prevented from rotating, either mechanically or due to a severe electrical issue, while the drive attempts to supply power. This condition leads to extremely high current draw, which can quickly overheat and damage the motor windings or the VSD's output stage. Immediate intervention is required to prevent component destruction and fire hazards.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Verify the motor windings for short circuits or earth faults using an insulation resistance tester (megger).

2. 4

   Confirm that the load connected to the motor is not jammed or excessively heavy for the motor's rating.