Flowserve 500+ Series Logix - Manual (Page 36)

User Instructions - Logix® 500+ Series Digital Positioners FCD LGENIM0105-10 11/13
flowserve.com 36
Figure 34: Characterization Curves
Select the appropriate curve as required by the process
design.
Custom - Select Custom for a standard 30:1 linear equal
percent rangeability curve. The curve may be customized
point-by point. To modify the Custom curve, use the
ValveSight DTM.
CAUTION: Changing the characterization curve may
cause the valve to move suddenly. Notify proper personnel
that the valve may stroke and if required, make sure the
valve is properly isolated before proceeding.
10.3.7 Configuration (Pressure Control)
The Configuration (Pressure Control) menu allows the user
to change the size of the pressure control window. This
window becomes active when the Valve Stability Switch is
set to “Hi”. The Valve Stability Switch optimizes the
response for valves and actuators with high friction levels.
When set to “Hi”, it slightly slows the response and will
normally stop limit cycling that can occur on high friction
valves.
Window - When the position of the valve gets within the
pressure control window, the positioning algorithm will
change to pressure control. This means the pressures will
be held constant (locked), improving the stability of the valve
position.
10.3.8 Configuration (Soft Limits and Shutoff)
Soft Limits allows the user to limit the movement of the valve.
Shutoff allows the user to tightly shut the valve with all
available force.
High Soft Limit and Low Soft Limit - This feature is used to
simulate physical blocks on the valve that restrict movement
past a set point. Once the Soft Limit is set, the positioner will
not attempt to move the valve position (final command)
beyond the set point, regardless of the analog or digital
command input signal.
CAUTION: Changing the Soft Limits may limit the
movement of the valve. The valve may not shut or open fully.
0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90 100
Fi
na
l C
om
m
a
nd
Command Input
Linear
MaxFlo
Linear
MaxFlo =%
Valdisk
Linear
Valdisk =%
ShearStream
Linear
ShearStream
=%
Custom
Table 18: Characteristic Curve Data
Command
Input
Final Command
Characterizatio
n DIP set to
“Linear”
Characterization
DIP set to
“Other”
Linear
MaxFlo
Linear
MaxFlo
=%
Valdisk
Linear
Valdisk
=%
Shear-
Stream
Linear
Shear-
Stream
=%
Custom
(Default)
(Linear =%)
0.0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5.0 5.00 6.50 1.00 13.00 4.00 25.00 8.00 0.62
10.0 10.00 11.60 2.00 20.00 6.00 35.00 14.00 1.35
15.0 15.00 16.20 3.00 26.25 7.80 44.00 17.00 2.22
20.0 20.00 20.50 4.40 32.10 9.30 50.20 21.00 3.25
25.0 25.00 24.60 5.80 37.50 11.50 55.50 24.00 4.47
30.0 30.00 28.50 7.40 42.60 14.00 60.20 27.50 5.91
35.0 35.00 32.40 9.30 47.40 16.50 64.30 31.50 7.63
40.0 40.00 36.20 11.20 51.80 19.30 68.00 35.50 9.66
45.0 45.00 40.00 13.50 56.00 22.50 71.50 39.50 12.07
50.0 50.00 43.80 16.10 60.00 26.00 74.70 43.90 14.92
55.0 55.00 47.60 19.10 63.60 30.00 77.70 48.10 18.31
60.0 60.00 51.50 22.40 67.20 34.70 80.50 52.80 22.32
65.0 65.00 55.50 26.20 70.60 39.60 83.20 57.40 27.08
70.0 70.00 59.50 30.60 73.90 45.10 85.90 62.40 32.71
75.0 75.00 63.80 35.70 77.20 51.30 88.40 67.50 39.40
80.0 80.00 68.20 41.70 81.30 57.80 90.80 72.90 47.32
85.0 85.00 73.00 48.90 84.00 64.80 93.20 78.60 56.71
90.0 90.00 78.40 57.70 87.80 72.50 95.50 84.70 67.84
95.0 95.00 85.00 69.20 92.10 81.30 97.80 91.20 81.03
100.0 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00
►Configuration
►Pressure Control
►Window
►Configuration
►Soft Limits & Shutoff
►High Soft Limit
►Low Soft Limit
►Upper Position Shutoff
►Lower Position Shutoff