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Rockwell Automation Publication 1444-UM001D-EN-P - June 2018
Chapter 4
Measurement Definition
DC
The remaining configurations are applied on the DC page for each channel of
the pair.
Ramp Differential Expansion measurements are configured using the
following controls.
Figure 81 - Ramp Angle
Table 39 - Radial Ramp Differential Expansion Measurement Controls
Parameters
Values
Comments
Units
Select from present
displacement units
Differential Expansion measurements are typically made using eddy
current probes or linear voltage differential transformers (LVDT).
Configuration of the units, time constant, Calibration Offset (there is
no sense control) are the same as for Normal Thrust measurements
(
Time constant
0.1…60.0 seconds
Calibration units
EU (0)
Volts (1)
Calibration offset
-50000…50000
Ramp angle
-45.000…45.000
Enter the angle of the ramp.
A ‘normal’ probe with a plain target has a ramp angle of 0°. Ramp
angle applies for both probes A and B.
Typical ramps have angles that range from about 9.5°…14.5° but
can be up to 45°. Ramp angles can be positive or negative.
Overall axial offset
-50000…50000
No value must be entered into the Overall Axial Offset entry box
unless the starting value for the expansion measurement is required
to start at other than a zero value due to DCS or other control system
requirements.
Overall radial offset
-25000…25000
Radial offset is not used.