# ID 70420

Characteristic filter frequency greater than half the sampling rate.
Description | According to Shannon's sampling theorem, the maximum cut-off frequency is (½*TA= cycle time of the NC controller). The cut-off frequency of the PT2 filter is calculated from the time constant to obtain fg = 1 / (2 * PI * P-AXIS-00438).
Response | Class | 7 | The filter is deactivated.
Solution | Class | 6 | Possible solutions:

- Increase time constant P-AXIS-00438 of PT2 filter
- Reduce the cycle time of the numerical control

Parameter | %1: | Logical axis number [-]
Logical axis number P-AXIS-00016 of concerned axis
%2: | Current value [-]
Number of concerned filter
%3: | Current value [-]
Type of filter (see axis filter FCT-A7)
%4: | Error value [Hz]
Actual cut-off frequency of the filter
%5: | Current value[-]
Sampler frequency of the NC (1 / TA)
Error type | -