HBK DSE, Руководство по эксплуатации

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DSE
WEB INTERFACE
Selecting filters
In the left-hand area of the page, you can connect up to five filters in series. Enter the
filter type and the cut-off frequency in the selection box of the relevant filter stage.
The first filter stage offers an IIR or FIR low-pass filter. In the second to fifth stages you
can choose between an FIR comb filter and an FIR filter for moving average. Enter the
cut-off frequency either using the keyboard or with the mouse wheel. Any change to the
filter settings is immediately displayed in the graph. As long as you do not apply changes,
the changes will be displayed in the simulation mode; after applying them, they will be
displayed in the device setting.
Alternatively, you can display the effect of the selected filters on a step function by
choosing the Step Response option.
You can add further filter stages using the icon and remove them using the icon.
Stages 1 and 2 cannot be removed, but you can disable them by not selecting a filter
type.
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When you have set the filters as you need, click on APPLY CHANGES to transfer the
values to the DSE.
Important
The settings are initially saved only temporarily. You can save them permanently in the
device, like all value changes, in the Parameter Sets menu.
7.5.1 Notes on the filters
FIR filter
These are low-pass filters with a very steep filter characteristic. Signal components that
are above the set cut-off frequency are strongly suppressed quite rapidly.
The cut-off frequency may be between 3 and 30 Hz.
IIR filter
These filters have a less steep filter characteristic than FIR filters.
The cut-off frequency may be between 0.1 and 30Hz.
Moving average
The moving average eliminates both the selected frequency and its integral multiples
(2nd, 3rd, 4th, ... multiples of the fundamental) in the measurement signal. This means
periodic interference with higher frequency components, such as square wave signals or
recurring pulses, can be reduced. The lower the selected frequency, however, the longer
the signal delay through the filter will be, and so the settling time of the output signal will
also be longer.
The cut-off frequency may be between 1 and 100 Hz.