Manualshelf

Instruction Manual

ManualsBrandsEmerson ManualsValve InstrumentationEmerson Fisher FIELDVUEDVC2000 Digital Valve Controller
51525354555657585960
Instruction Manual
D103176X012
Detailed Setup and Calibration
April 2014
54
1. Set the current source to the target value shown on the display. The target value is the Input Range Low value. Press
OK.
2. The following message appears:
Use Increase and
Decrease selections
until the displayed
current matches the
target.
Press OK when you have read this message.
3. The value of the Analog Input appears on the display. Press OK to display the adjustment menu.
4. From the adjustment menu, select the direction and size of adjustment to the displayed value. Selecting large,
medium, and small adjustments causes changes of approximately 0.4 mA, 0.04 mA, and 0.004 mA, respectively. If
the displayed value does not match the current source, press OK, then repeat this step (step 4) to further adjust the
displayed value. When the displayed value matches the current source, select Done and go to step 5.
5. Set the current source to the target value shown on the display. The target value is the Input Range High value.
Press OK.
6. The following message appears:
Use Increase and
Decrease selections
until the displayed
current matches the
target.
Press OK when you have read this message.
7. The value of the Analog Input appears on the display. Press OK to display the adjustment menu.
8. From the adjustment menu, select the direction and size of adjustment to the displayed value. Selecting large,
medium, and small adjustments causes changes of approximately 0.4 mA, 0.04 mA, and 0.004 mA, respectively. If
the displayed value does not match the current source, press OK, then repeat this step (step 8) to further adjust the
displayed value. When the displayed value matches the current source, select Done and go to step 9.
9. Place the instrument In Service and verify that the analog input displayed matches the current source.
Auto Calibrate Travel
1. The auto calibration procedure is automatic. It is completed when the Calibrate menu appears.
During calibration, the instrument seeks the high and low end points and the minor loop feedback (MLFB) and
output bias. By searching for the end points, the instrument establishes the limits of physical travel, i.e., the actual
travel 0 and 100% positions. This also determines how far the relay beam swings to calibrate the sensitivity of the
beam position sensor.
Adjusting the minor loop feedback bias is done around mid travel. The valve position is briefly moved back and forth
to determine the relay beam position at quiescence. Essentially, it establishes the zero point for the Minor Loop
Feedback circuit. The back and forth motion is performed to account for hysteresis.
Adjusting the output bias aligns the travel set point with the actual travel by computing the drive signal required to
produce 0% error. This is done while the valve is at 50% travel, making very small adjustments.