Analog Input Calibration; Relay Adjustment; Double-Acting Relay - Fisher FIELDVUE DVC6200 Instruction Manual

DVC6200 Digital Valve Controller

Analog Input Calibration (1-3-2-2)

To calibrate the analog input sensor, connect a
variable current source to the instrument LOOP+ and
LOOP− terminals. The current source should be
capable of generating an output of 4 to 20 mA. From
the Calibrate menu, select Sensor Calibration, Analog
In Calib, then follow the prompts on the Field
Communicator display to calibrate the analog input
sensor.
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
5
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.
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8. From the adjustment menu, select the direction and
size of adjustment to the displayed value. 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.

Relay Adjustment (1-3-3)

Before beginning travel calibration, check the relay
adjustment. To check relay adjustment, select Relay
Adjust from the Calibrate menu, then follow the
prompts on the Field Communicator display. Replace
the digital valve controller cover when finished.
Note
Relay B and C are not user-adjustable.

Double-Acting Relay

The double-acting relay is designated by "Relay A" on
a label affixed to the relay itself. For double-acting
actuators, the valve must be near mid-travel to
properly adjust the relay. The Field Communicator will
automatically position the valve when Relay Adjust is
selected.
Rotate the adjustment disc, shown in figure 5-1, until
the output pressure displayed on the Field
Communicator is between 50 and 70% of supply
pressure. This adjustment is very sensitive. Be sure to
allow the pressure reading to stabilize before making
another adjustment (stabilization may take up to 30
seconds or more for large actuators).
If the low bleed relay option has been ordered
stabilization may take approximately two minutes
longer than the standard relay.
Relay A may also adjusted for use in single-acting-
direct applications. Rotate the adjustment disc as
shown in figure 5-1 for single-acting direct operation.
CAUTION
Care should be taken during relay
adjustment as the adjustment disc may
disengage if rotated too far.
September 2010