Interface Inc.
●
7401 East Butherus Drive, Scottsdale, Arizona 85260 USA
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Phone 480.948.5555
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Fax 480.948.1924
www.interfaceforce.com
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Email:
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ORDER TOLL-FREE 800.947.5598
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Data frequency and filter
Analog filter
The integrated analog filter is a first-order low-pass filter with a cut-off frequency of 1 kHz. It is
set as an antialiasing filter for the A-D converter. This filter is permanently installed and cannot
be changed.
Digital filter
The digital filter is indirectly set with the data frequency. The effective data frequency may
differ slightly from the set (nominal) data frequency. The grey shaded settings are
recommended as with these settings faults with a mains frequency of 50 Hz are best
suppressed by the integrated “notch filter”.
Data frequency
in Hz (nominal)
Data frequency
in Hz
(effective)
Notch
frequency in
Hz
-3db cut-off
frequency in Hz
(digital filter)
Parameters for “set
frequency”
250
208
1000
441
0xAA
125
114
500
221
0xA9
25
24.4
100
44.2
0xA8
15
14.7
60
26.5
0xA7
12.5
12.4
50
22.1
0xA6
7.5
7.5
30
13.3
0xA5
6.25
6.25
25
11.1
0xA4
3.75
3.75
15
6.63
0xA3
2.5
2.5
10
4.42
0xA2
1.25
1.25
5
2.21
0xA1
0.625
0.625
2.5
1.1
0xA0
Table 14: data frequencies and filter properties
