Emerson Fisher FIELDVUE DVC6000f, Инструкция по эксплуатации

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DVC6000f Digital Valve Controllers
December 2009 4-26
pressure that corresponds to 0% valve travel when
Zero Power Condition is closed, or 100% valve travel
when Zero Power Condition is open. The pressure
must be less than the Pressure Range Hi.
Input Characterization
(TB
>
Configure/Setup
>
Detailed Setup
>
Response
Control
>
Input Characterization)
Input Characterization (INPUT_CHAR [50]) defines
the relationship between the travel target and the
setpoint received from the output block. Travel target
is the output from the characterization function.
Custom Characterization Table
(TB
>
Configure/Setup
>
Detailed Setup
>
Response
Control
>
Custom Characterization Table)
You can select from the three fixed input
characteristics shown in figure 4-1 or you can select a
custom characteristic. Figure 4-1 shows the
relationship between the travel target and travel set
point for the fixed input characteristics.
You can specify 21 points on a custom characteristic
curve. Each point defines a travel target, in % of
ranged travel, for a corresponding set point, in % of
ranged set point. Set point values range from
−
25.0%
to 125%. Before modification, the custom
characteristic is linear. You cannot modify the custom
points if the Input Characterization (INPUT_CHAR
[50]) is set to custom.
Outblock Selection
(TB
>
Configure/Setup
>
Detailed Setup
>
Response
Control
>
Outblock Selection)
Outblock Selection (OUTBLOCK_SEL [96]) defines
which output function block will control the setpoint of
the valve. The output block that is not selected will
shed its mode to reflect that it does not have control of
the valve.
Alerts
The DVC6000f provides two levels of alerts;
Instrument alerts and PlantWeb alerts.
Instrument Alert Conditions
Instrument Alert Conditions, when enabled, detect
many operational and performance issues that may be
of interest. To view these alerts, the user must open
the appropriate status screen on a host such as
DeltaV, ValveLink software or a Field Communicator.
T
ravel T
arget,
%
Set Point, %
−
25 0 125 100
−
25 0 125 100
−
25 0 125 100
Input Characteristic Linear
Input Characteristic Equal Percentage
Input Characteristic Quick Opening
100
0
−
25
125
T
ravel T
arget,
%
100
0
−
25
125
T
ravel T
arget,
%
100
0
−
25
125
A6535-1/IL
Figure 4-1. Travel Target Versus Ranged Set Point, for Various
Input Characteristics (Zero Power Condition = Closed)
Set Point, %
Set Point, %
4