Emerson Fisher FIELDVUE DVC2000, Инструкция по эксплуатации

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Detailed Setup and Calibration
July 2009 4-13
Note
If optional limit switches are being
used, power must be applied to the
switch circuits throughout the
calibration routine. Failure to power
the switches may result in incorrect
switch orientation.
Switch 1 Trip Point—Defines the threshold for the
limit switch wired to ter41 and
−
42 in percent
of calibrated travel.
Switch 1 Closed—Configures the action of the
limit switch wired to ter41 and
−
42. Selecting
ABOVE configures the switch to be closed when the
travel is above the trip point. Selecting BELOW
configures the switch to be closed when the travel is
below the trip point. Selecting DISABLED removes the
icons and status from the display.
Switch 2 Trip Point—Defines the threshold for the
limit switch wired to ter51 and
−
52 in percent
of calibrated travel.
Switch 2 Closed—Configures the action of the
limit switch wired to ter51 and
−
52. Selecting
ABOVE travel is above the trip point. Selecting
BELOW configures the switch to be closed when the
travel is below the trip point. Selecting DISABLED
removes the icons and status from the display.
Note
Switch #2 is only operational if power
is applied to switch #1 also. Switch #2
cannot be used alone.
Transmitter Action—This configures the
relationship between the valve travel and the position
transmitter output signal. If you select CLOSED, the
transmitter will send 4 mA when the valve is closed. If
you select OPEN, the transmitter will send 4 mA when
the valve is open.
A switch is located on the options board to select the
transmitter fail signal (high+ or low
−
). High+ will result
in a current output of
>
22.5 mA upon transmitter
failure. Low
−
will result in a current output of
<
3.6 mA. Refer to figure 3-6 for location and switch
selection.
Tuning
WARNING
Changes to the tuning set may cause
the valve/actuator assembly to stroke.
To avoid personal injury and property
damage caused by moving parts,
keep hands, tools, and other objects
away from the valve/actuator
assembly.
Automatic
The auto tuner is used to optimize digital valve
controller tuning. It can be used on most sliding-stem
and rotary designs, including Fisher and other
manufacturers’ products. Moreover, because the auto
tuner can detect internal instabilities before they
become apparent in the travel response, it can
generally optimize tuning more effectively than manual
tuning.
Access the auto tuner by selecting Auto Tuner from
the Calibrate menu. Follow the prompts on the Field
Communicator display to optimize digital valve
controller tuning.
Manual
If the auto tuner does not provide the desired
responsiveness, you can manually tune the DVC2000.
Refer to Setting Response, page 4-7.
Calibration
WARNING
During calibration the valve will move
full stroke. To avoid personal injury
and property damage caused by the
release of pressure or process fluid,
provide some temporary means of
control for the process.
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