User Manual

Compact IO™ Isolated HART Analog Input Module
U ser 's M a n u a l 0 300 21 5- 03 R ev. A
6-10
Figure 6-2 (Frequency Response)
The cut-off frequency for each channel is defined by its filter frequency selection. C hoo se
a filter frequency so that your fastest changing sig nal i s b elow that of the filter’s cut-off
frequency. The cut-off fre quenc y shoul d not be confused with the update time. The cut-
off frequency relates to how the digital filter attenuates frequenc y components of the
input signal.
The update time defines the rate at which an input channel is scanned and its channel data
word is updated.
28.5Hz Filte r
-120
-100
-80
-60
-40
-20
0
0 102030405060708090
Filter Rejection (dB)
50 H z F ilter
-120
-100
-80
-60
-40
-20
0
0 20 40 60 80 100 120 140 160
Filter Rejection (dB)
60Hz Filte r Operation
-120
-100
-80
-60
-40
-20
0
0 50 100 150 200
Filter Rejection (dB)
300Hz Filter Ope r ation
-120
-100
-80
-60
-40
-20
0
0 200 400 600 800 1000
Filter Rejection (dB)
360Hz Filte r Operation
-120
-100
-80
-60
-40
-20
0
0 200 400 600 800 1000 1200
Filter Rejection (dB)