Which products are affected?
All 8200vector/motec with software up to and including V2.1
What happens?
The skip frequency bandwidth set under C0628 affects all skip frequencies . All skip frequencies are active because of the 480 Hz setting in the default setting. As a result, the overlapping of skip frequencies can lead to undesired field frequencies, especially with settings of C0628 > 80 %.
Example: Bandwidth C0628 = 95 %
C0625 = 20 Hz C0626 = 480 Hz
min. skip frequency 1 of C0625 is 1 Hz min. skip frequency 2 of C0626 is 24 Hz
max. skip frequency 1 of C0625 is 39 Hz max. skip frequency 2 of C0626 is 936 Hz
This means that the skip frequency 1 is exceeded with setpoints > 39 Hz. However, the frequency is limited to the min. skip frequency 2 (24 Hz). With it the output frequency of the inverter is restricted to the range 0 to 1 Hz.
When does the problem occur?
- masking of resonance frequenzies
- Suppression of vibrations
- in combination with adjustments of high skip frequency bandwidth C0628 or at higher rotating frequencies
Possible diagnostics?
Check the adjustments C0625 to C0628 and determinate the limits:
- min. limit: skip frequency * (1 - bandwidth * skip frequency)
- max. limit: skip frequency * (1 + band width * skip frequency)
