Flowserve Logix 420, User Instructions

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Logix
®
420 Digital Positioner FCD LGENIM0106-07-AQ – 10/15
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Select the appropriate curve as required by the process design.
Custom – Select Custom for a standard 30:1 linear equal percent rang-
ability curve. The curve may be customized point-by point. To modify
the Custom curve, use the ValveSight DTM.
1
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)
► Configuration
► Pressure Control
► Window
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.
Table 13: Characteristic Curve Data
Command
Input
Final Command
Characterization
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
0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90 100
Final Command
Command Input
Linear
MaxFlo
Linear
MaxFlo =%
Valdisk
Linear
Valdisk =%
ShearStream
Linear
ShearStream
=%
Custom
Figure 12: Characterization Curves