Rockwell Automation 1769-IR6 Compact I/O 1769-IR6 RTD/Resistance Input Module - Manual (Page 63)

Rockwell Automation Publication 1769-UM005B-EN-P - March 2012 63
Module Data, Status, and Channel Configuration Chapter 4
Channel Cutoff Frequency
The channel cutoff frequency (-3 dB) is the point on the input channel
frequency response curve where frequency components of the input signal are
passed with 3 dB of attenuation. The following table shows cutoff frequencies
for the supported filters.
All frequency components at or below the cutoff frequency are passed by the
digital filter with less than 3 dB of attenuation. All frequency components
above the cutoff frequency are increasingly attenuated, as shown in the graphs
below for several of the input filter frequencies.
Table 11 - Filter Frequency versus Channel Cutoff Frequency
Filter Frequency Channel Cutoff Frequency
10 Hz 2.62 Hz
50 Hz 13.1 Hz
60 Hz 15.7 Hz
250 Hz 65.5 Hz
500 Hz 131 Hz
1 kHz 262 Hz
TIP Channel cutoff frequency should not be confused with
channel update time. The cutoff frequency simply
determines how the digital filter attenuates frequency
components of the input signal. See Determining Module
Update Time on page 72.