Remedied from:
8400 StateLine SW V3.00 onwards
8400 HighLine SW V2.00 onwards
Behaviour of the new version?
The above-named software version rectifies this functional restriction.
Which products are affected?
8400 StateLine SW ≤ V2.00
8400 HighLine SW ≤ V1.00
What happens?
If it is connected to a rotating motor while the 'Servo Control' (SC) operating mode is selected a slight jerk (torque surge) can be observed at the motor shaft. When the operating modes 'Servo control' (SC) and 'V/f characteristic control with feedback' (VFCplus) are used, the behaviour described before can also be observed when the frequency inverter returns from an overvoltage message to the standard operating mode.
After controller enable or return from the overvoltage message the ramp function generator is loaded with the actual speed value and stopped for the time required for magnetising.
When does the problem occur?
The problem occurs if the motor shaft is still rotating and the frequency inverter is enabled while the 'servo control' (SC) operating mode is selected or when the frequency inverter returns after an overvoltage message to the standard operating mode.
Possible diagnostics?
Observe the actual motor speed. Can a jerk be detected at the rotating shaft when enabling the controller?
Short-term measures/recommendations?
None.
Evaluation:
It may happen that in exceptional situations the system is loaded by short torque surges.
Published with service message No. 2009/02
