Rockwell Automation 1440-SDM02-01RA XM-124 Standard Dynamic Measurement Module - Manuel (Page 66)

66 Rockwell Automation Publication 1440-UM001C-EN-P - May 2014
Chapter 2 Configure the XM-124 Standard Dynamic Measurement Module
The Tracking Filter measurement mode performs the DC Bias, Overall, FFT,
TWF, Tracking Filter magnitude and phase measurements. This is similar to the
XM-123 Aeroderivative module’s Tracking Filter measurement set except the
XM-123 does not perform the FFT and TWF measurements.
The Band Pass Filter measurement mode performs the DC Bias, Overall, FFT,
TWF, and Band Pass Filter measurements. This is similar to the XM-123
Aeroderivative module’s Band Pass Filter measurement set except the XM-123
does not perform the FFT and TWF measurements.
The Thrust Position measurement mode performs a Thrust Position
measurement in addition to the Standard measurement mode measurements.
This is the same set of measurements performed by the XM-124 V6 firmware
while the Thrust Position measurement is enabled. This is also like the position
measurement performed by the XM-320 Position module when it is configured
in its Normal mode.
The Eccentricity measurement mode performs the DC Bias and Eccentricity
measurements. Eccentricity is the measure of the amount of bow in a rotor. The
lower the eccentricity value, the more straight the shaft. Rotor bow can be a fixed
mechanical bow, or it can be a temporary bow caused by uneven thermal heating
or simply by the weight of the rotor (gravity bow). The Eccentricity
measurement mode is suitable for virtually all types of rotating and reciprocating
machinery where rotor bow must be measured prior to or during startup. This
eccentricity measurement is the same as the eccentricity measurement performed
by the XM-120E Eccentricity module.
Signal Processing
The Signal Processing group box options apply to the Standard, Alternating gSE,
Tracking Filter, and Band Pass Filter measurement modes. These settings affect
the standard Overall, FFT, and TWF measurements.
In this field Values are Comments
Full Scale Choose the maximum signal level expected to be processed by the
channel. If the full scale value is peak or peak-to-peak, select the
measurement performed (true or calculated) to produce the overall
value. The default value and the available values depend on the
Transducer Nominal Sensitivity selection.
If the Engineering Units of the selected Full Scale value
require integration, from the Engineering Units of the
selected Nominal Sensitivity, then an analog 2 kHz Low Pass
Filter will be applied prior to the measurement.
By assuring the absence of high-frequency content, gains can
be applied to maximize the accuracy of the measurements
below the LPF corner frequency.