Filter
The measured value of each analog input can be filtered with a digital filter.
Notice | |
Measured value jumps when enabling or disabling filters When filters are enabled or disabled, short-term measured value jumps can occur in the process data that do not correspond to the physical values. |
 | Filters influence the EtherCAT synchronization mode If one or more filters are activated, the device will automatically run in “Free Run” synchronization mode. |
All filters are disabled in the factory setting.
You can enable the filter for each input individually by setting the corresponding CoE parameter "Enable filter" to TRUE:
Channel | "Enable filter" |
|---|---|
1 | 0x8010:06 |
2 | 0x8020:06 |
Select filter type
The factory setting of the filter type is "IIR 1".
You can select the filter type for each input individually in the CoE parameters "Filter Settings":
Channel | "Filter Settings" |
|---|---|
1 | 0x8010:15 |
2 | 0x8020:15 |
There is a choice of two filter types. Use the following description to select a suitable filter type for your application.
FIR filter
The filter works as a notch filter and determines the conversion time of the module. The higher the filter frequency, the faster the conversion time. A 50 Hz and a 60 Hz filter are available.
Notch filter means that the filter has zeros (notches) in the frequency response at the filter frequency and multiples thereof, i.e. it attenuates the amplitude at these frequencies.
The FIR filter operates as a non-recursive filter.
IIR filter
The filter with IIR characteristics is a discrete time, linear, time invariant filter that can be set to eight levels (level 1 = weak recursive filter, up to level 8 = strong recursive filter)
The IIR can be understood to be a moving average value calculation after a low-pass filter.