Logix
®
Digital Positioners FCD LGENIM0110-0 05/16
flowserve.com
28
Figure 25: Local User Interface
21.3 Configuration Switch Settings
Before placing the unit in service, set the Configuration
Switches to the desired control options.
NOTE:
The Configuration Switch settings are activated
only by performing a Stroke calibration (pressing the
“QUICK-CAL” button for 3 seconds). However, the
Configuration Switch settings may be edited from the DTM
or Handheld at any time.
21.3.1 Air Action Switch
This must be set to match the configuration of the
valve/actuator mechanical tubing connection since the
tubing determines the air action of the system.
ATO - Increasing pressure from Port 1 causes the valve to
open.
ATC - Increasing pressure from Port 2 causes the valve to
close.
21.3.2 Valve Action Switch
This must be set to match the configuration of the actuator
and is used in some diagnostics.
Double - Select Double when both sides of the actuator are
pressurized.
Single - Select Single when only one side of the actuator is
pressurized.
21.3.3 Signal at Closed Switch
Normally this will be set to 4 mA for an Air-To-Open
actuator configuration, and 20 mA for Air-To-Close.
4 mA - Selecting 4 mA will make the valve close when the
signal is low (4 mA) and open when the signal is high (20
mA).
20 mA - Selecting 20 mA will make the valve close when
the signal is high (20 mA) and open when the signal is low
(4 mA).
NOTE:
When using an Analog Output (AO) function of
the Multi-Function Card, the AO signal corresponds with
the Signal at Closed selection. If the valve closes with a 4
mA signal, the AO will show a 4 mA signal at closed. If the
valve closes with a 20 mA signal, the AO will show a 20 mA
signal at closed.
21.3.4 Characterization Switch
The Characterization Switch allows a better match between
the input command and the actual fluid flow through the
valve. This feature is typically used with valves that have
non-linear flow characteristics. The positioner makes a
correction by applying an adjustment to the input command
according to a characterization curve.
Linear - Select Linear if the actuator position should be
directly proportional to the command input signal. (For most
rotary valves, this setting gives an =% Cv characteristic due
to their inherent =% characteristics.)
Other - Select Other if one of the pre-set characterization
curves or a custom curve is desired. The default will be the
Custom curve which is populated with a standard 30:1
equal percent rangeability curve which generally opens
less than the input command (See Figure 26). To select
one of the other curve options, use a Handheld or the
ValveSight
®
DTM. To modify the Custom curve, use the
DTM.
Figure 26: Characterization Curves
21.3.5 Auto Tune Switch
This
switch
controls
whether
the
positioner
will
automatically tune itself during the stroke calibration
(Quick-Cal), or use preset tuning parameters.
On - Selecting On enables an auto tune feature that will
automatically determine the positioner gain settings. The
automatic tuning will be based on response parameters
measured during the latest Quick-Cal. The valve response
is a combination of these response parameters and the
current position of the Selectable GAIN Switch.
Off - Selecting Off forces the positioner to use one of the
factory preset tuning sets determined by the Selectable
GAIN Switch. Settings “B” through “J” are progressively
higher predefined tuning sets.
0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90 100
Fi
nal
C
om
m
a
nd
Command Input
Linear
Custom
