Allen-Bradley 1444-AOFX00-04RB, User Manual, Page: 467 / 550

Rockwell Automation Publication 1444-UM001D-EN-P - June 2018 467
CIP Objects Appendix A
Source of Speed Data
Any one of the following can be identified as the speed reference for Normal
CM data.
Waveform Record Length
Number of samples = 256 * (2^(Index))
FFT Resolution
Defines the FFT line resolution that is used for the Normal CM data FFT. For
Advanced CM data, additional line resolutions can be requested.
The Normal CM data object specifies the transient dynamic data, note
however that it is limited to a maximum of a 900 line FFT and 2048 point
TWF. Normal CM data can be set to higher lines/samples and this setting
reflects in Trend and Alarm data but stored Transient Data is 900 line FFT and
2048 point TWF).
Value Description
0 Tacho/Speed 0
1 Tacho/Speed 1
Index 0 1 2 3 4 5
Samples 256 512 1024 2048 4096 8192
Index TWF Samples FFT Lines
Base FFT
Lines
(1)
(1) The Base FFT Lines represent the size of the raw processed FFT and are the number of lines returned if no adjustments are made
for decimation and filtering. Control of application of relevant factors for the applied decimation and filtering is provided in the
SpecialRequest member of the CM Record Request structure (
Table 206 ).
Decimation
None Alternate
Path
(2)
(2) Or if -60 dB filter is applied (Aeroderivative Measurement Type)
Primary
Path
(3)
(3) And the standard -24 dB/octave filter is applied.
4 4096 1600 1800 1000 600
3 2048 800 900 500 300
2 1024 400 450 250 150
1 512 200 225 125 75
0 256 100 112 67 32