Corrected from:
- Inverter Drives 8400 TopLine V15.01.00
Response of the new version:
Now, the motor encoder position is the actual value of the position controller during QSP. If required, the behaviour of the previous version (using the actual position encoder value) can be restored via C104 bit4=TRUE.
Which products are affected?
Inverter Drive 8400 TopLine up to firmware version 12.01.00.00
What happens?
The position of the position encoder is used as actual value for the position control.
If the encoder position at standstill changes implausibly with regard to the actual machine position (e.g. beam interruption of an SSI laser encoder), the position controller correction causes a movement.
When does the problem occur?
If two different encoders for the speed and position feedback are used
Diagnostics options?
For testing purposes, the evaluation of the position encoder position can be changed, e.g. by changing C1111/1. If the position control is at standstill by QSP active, the position controller correction directly causes a movement. If the actual position of the motor encoder was used, no movement would be caused.
Short-term measures/recommendations?
None.
Evaluation:
Generally it is expected that, at active QSP at standstill, a position control to the actual position of the motor encoder takes place. If the restriction coincides with an error in the actual position, an unexpected movement during an active QSP may occur.
Since this is coincidental, the detection of the behaviour would also be coincidental.
