Which products are affected?
9300 vector 0.37…90 kW SW V2.1
What happens?
The motor current increases until the clamp limit during the acceleration process and the drive controller indicates OC1 TRIP (overcurrent).
When does the problem occur?
If the automatic DCB function is activated in the vector control mode, the drive controller internally sets the IMP inhibit during standstill after a specified time. If a setpoint is selected afterwards, the drive starts to accelerate without a previous magnetisation of the motor.
Possible diagnostics?
Record the motor current MCTRL-IACT during the acceleration process using an oscilloscope function.
Short-term measures/recommendations?
Magnetise the motor through QSP after controller enable. Start the speed ramp function generator afterwards.
Evaluation:
The control quality of the vector control mode can decrease without a correct magnetisation and an operation in the vector control mode is not possible. The incorrect behaviour occurs immediately during commissioning.
In order to identify the cause for the possible bad drive performance during commissioning the start-up engineer requires general knowledge about the operating mode 'vector control'.
