5/12/2017
TECH-538/D.W.O. 23160
Page 81 of 189
Description of Functions
Characterization
Path:
“Configure/Setup” menu -> “2-Advanced Setup” -> “2-1-1 Configuration”
Figure 8-34 – Characterization function
This function sets the flow characteristic of the positioner. It allows the user to adjust the opening-closing ratio
between the positioner setpoint to “actual-valve-position” in order to compensate for non-linear valve flow
characteristics. This allows the positioner-setpoint to represent a closer approximation to the actual flow.
The options are
Linear
,
Percent
,
Quick Opening
and
Custom
. When Equal Percentage and Quick Opening are
selected, the internal setpoint and valve position will not follow the actual setpoint value sent to the ICoT and the
valve will open or close according to a non-linear curve characteristics. The
Linear
option doesn’t modify the SP.
Figure 8-35 – Valve flow characteristics
21
Some options may not be available in all models.
VALVE POSITION % OF TRAVEL
QUICK OPENING
80
60
40
20
0
0
20
40
60
80
100
100
EQUAL PERCENTAGE
LINEAR
VALVE FLOW CHARACTERISTICS