Over-current during Acceleration

What does E03 mean?

This fault signifies an excessive current draw by the motor during its acceleration phase. Common causes include a short circuit in the motor wiring, the motor being mechanically locked, an overly aggressive acceleration time setting for the load, or insufficient motor parameters in the drive.

• Acceleration time (Parameter P1-10) set too short for the connected mechanical load's inertia, demanding excessive torque.
• Motor winding short circuit (phase-to-phase or phase-to-ground) or motor cable insulation failure.
• Mechanical binding or seizure in the driven equipment (e.g., gearbox, pump impeller) preventing smooth acceleration.
• Incorrect current limit setting (Parameter P1-07), allowing current to exceed safe operating levels during transients.
• Motor rated current (Parameter P1-03) incorrectly set too high, masking true overcurrent conditions during acceleration.

Click steps to track your progress.

1. 1

   Increase Acceleration Time (Parameter P1-10) by 20-50% to reduce the initial current surge.

2. 2

   Measure insulation resistance between motor output terminals U, V, W and between each terminal and ground (PE) with a megohmmeter (insulation tester).

3. 3

   Verify the mechanical freedom of the driven load by decoupling the motor and manually rotating the load shaft.

4. 4

   Check and adjust the current limit (Parameter P1-07) to a suitable level, typically 150-180% of the inverter's rated current.

5. 5

   Monitor motor current (display parameter d0-03) during acceleration to identify peak current values.