Moniteur 50 Series SMART Positioners - Manual (Page 69)

Operation
4-7
Positioner SIPART PS2/SIPART PS2 PA
C79000-G7476-C150–01
Instrument 1 Instrument 2
100 %–SPRE 100 %–SPRA SPRA SPRE
[0 % to 100 %]
y = x
100 %
0 %
Instrument 1
Instrument 2
6.SDIR = FALL
6.SDIR = riSE
J
W
Positioning range 1 Positioning range 2
Total positioning range
100 %
Fig. 4-5 Example: split-range operation with two instruments
Setpoint ramp
The setpoint ramp takes effect in automatic mode and limits the rate of
change of the active setpoint. When the instrument is switched from
manual mode to automatic mode the active setpoint is matched to the
setpoint on the instrument via the setpoint ramp.
This bumpless changeover between manual and automatic avoids
overpressures in long pipes.
In setting TS = Auto the slower of the two actuating times determined
during initialization is used for the setpoint ramp.
Setpoint function (see Fig. 4-6)
With this function, non–linear valve characteristic curves can be lineari-
zed and on linear valve characteristic curves, any flow characteristics
can be emulated.
Three valve characteristic curves are stored in the instrument
❑ equal percentage 1 : 25 (10.SFCT = 1:25)
❑ equal percentage 1 : 50 (10.SFCT = 1:50)
❑ inverse equal percentage 1 : 25 (10.SFCT = FrEE,
factory setting)
9.TS
10.SFCT