Technical Specifications

ValVueFF Software Interface to FVP
72
GE Energy
Figure 69 Tuning Wizard Error Message Boxes
NOTE Before running the Travel Calibration Wizard checks that Tight
Shut Off, Full Open, and Position Limits are disabled. Select
Next to see the Position Control Limits Wizard, shown in
Figure 71. Select Back to return to the Travel Calibration
Wizard. If changes are needed select Next to complete the
Wizard and install the changes. Restart the Setup Wizard.
Step 4: Travel Calibration Wizard
The mechanical stops on some actuators may allow the valve to move beyond it's rated
travel. The next wizard allows adjustment of the valve travel to correspond to the travel
indicator on the actuator. In the example shown the valve has been moved to 100% travel
mark on the actuator by trial and error. The FVP positioner indicates that the position
corresponding to 100% rated travel is 93.5% of the measured mechanical travel. If this is
correct select the span control and select Apply Calibration. Select Yes to the
confirmation dialog box Are you sure you want to apply travel calibration?. This method is
also used to adjust the 0% position to correspond to the valve's actual closed position and
to correct nonlinear travel by adjusting the position at which the valve is 50% open.
If Travel Calibration is used to modify valve travel, the initial values shown in Figure 70
may require corresponding modifications. For example, if the travel has been short
stroked so that at 100% calibrated travel the valve is at 80% of mechanical limits,
increase the Full Open Above and Position Upper Limit values to 138% (110%/.8).
Similarly, if the valve is calibrated to allow over-travel at the valve seat, reduce Tight
Shutoff and Position Lower Limit. For example, if the valve is closed at 12% of
mechanical travel, then reduce TS and Position Low Limit to -22%.