Short circuit in motor output terminals

What does F1.1 mean?

An overcurrent or faulty output stage control has been detected, causing the output stage to be inhibited by hardware. This often indicates a short circuit at the motor output, excessive motor current, or a defective power output stage. Failure to resolve risks severe damage to the drive and connected motor.

• Short circuit between two motor phases (U-V, V-W, U-W) in the motor cable or motor windings.
• Short circuit between any motor phase (U, V, W) and ground (PE) in the motor cable or motor's connection box.
• Damaged motor cable insulation due to mechanical stress, abrasion, or chemical exposure.
• Internal winding short circuit within the motor (e.g., turn-to-turn fault) causing excessive current draw.
• Motor current exceeding the drive's instantaneous overcurrent limit (e.g., 200% of rated output current).

Click steps to track your progress.

1. 1

   Disconnect motor power cable from drive output terminals (U, V, W). Measure resistance between each phase terminal (U-V, V-W, U-W) and each phase to ground (U-PE, V-PE, W-PE).

2. 2

   Verify motor cable insulation integrity using a megohmmeter (megger) test at 500VDC or 1000VDC from each phase to ground and phase to phase.

3. 3

   Visually inspect the motor cable for any signs of damage, cuts, or abrasion, especially where it enters conduits or passes through glands.

4. 4

   Measure the motor winding resistance (U-V, V-W, U-W) at the motor terminals and compare to the motor's nameplate data or specifications.

5. 5

   Check drive parameters P3-01 (Motor rated current) and P3-02 (Motor overload factor) to ensure they are correctly set for the connected motor.