Corrected from:
- Inverter Drives 8400 HighLine V16.00.00
- Inverter Drives 8400 TopLine V16.00.00
Response of the new version:
For internal calculations, the value of C578 is limited to 16.0ms. C578 can, however, still be set in the value range of 0.1-6000ms.
What happens?
With a reset time C578<16ms, the control characteristics in the field weakening range are much poorer than e.g. with C578=16.1ms.
When does this behaviour occur?
If the following conditions are met, a counter overflow will occur in the internal control calculations which will lead to unstable control:
- Servo control ASM C6=2 is selected as motor control mode
- C577=0 (P component of field weakening controller is deactivated)
- C578<16.0ms
Which products are affected?
- Inverter Drives 8400 HighLine V16.00.00
- Inverter Drives 8400 TopLine V16.00.00
Short-term measures:
The reset time in the field weakening controller should not fall below C578=16ms.
Evaluation/recommendations:
When the P component in the field weakening controller is deactivated C577=0, the required reset times will, as expected, always be well above C578=16ms. Accordingly, the behaviour should actually not occur if the field weakening controller settings are suitable.
