Allen-Bradley 1444-TSCX02-02RB User Manual page 162

Chapter 4 Measurement Definition
162
Monitoring Thrust Position with an HMI
The typical approach in setting the HMI to visualize the rotor thrust position
is to configure the monitor to show a plus value for thrust against the active
pads (sometimes referred to as "normal"). Also, the monitor can show a minus
value for thrust against the inactive pads (sometimes referred to as "counter").
The monitor zero value must be set with the rotor hard against the active
thrust pads, or at a setting that is provided by the machine OEM who can
advise on the Hot Float.
Example: Steam Turbine application (imperial units) with Rotor displaying
five mils of movement against the active thrust pads.
This movement could represent the normal running position for this rotor due
to the effect of the increased Hot Float with the machine at running
temperature and load.
IMPORTANT Do not change the probe gap setting or the monitor zero position when the
machine is running otherwise all reference to rotor position is lost.
Always refer to the machine OEM for specific instructions about setting the
zero position of the rotor, which can differ from the preceding information.
Rockwell Automation Publication 1444-UM001D-EN-P - June 2018