Spectrum Controls 1769sc-HART Modules - Manual (Page 59)

Chapter 4: Module Data, Status, and Configuration
User's Manual 0300215-03 Rev. A
6-9
Table 6-5 (Filter Frequency and Step Response)
Filter Frequency Step Response
1
28.5 Hz 108 ms
50 Hz 62 ms
60 Hz 52 ms
300 Hz 12 ms
360 Hz 10 ms
1
The channel update time is equal t o t he channel st ep respose.
Channel Cut-Off Frequency
The filter cut-off frequency, -3 dB, is the point on the frequency response curve where
frequency components of the input signal are passed with 3 dB of attenuation. The
following table shows cut-off frequencies for the supported filters.
Table 6-6 (Filter Frequency versus Channel Cut-off Frequency)
Filter Frequency Cut-off Frequency Rejection
28.5 Hz 2.3 Hz 67 db @ 50/60 Hz
50 Hz 4.0 Hz 96 db @ 50 Hz
60 Hz 4.7 Hz 96 db @ 60 Hz
300 Hz 24 Hz 25 db @ 50 Hz
360 Hz 28 Hz 25 db @ 60 Hz
All input frequency components at or below the cut-off frequency are passed by the
digital filter with less than 3 dB of attenuation. All frequency components above the cut-
off frequency are increasingly attenuated as shown in Figure 6-2 (Frequency Response).