Emerson FIELDVUE DVC6200f, Instruction Manual

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DVC6200f Digital Valve Controller
November 2010 160
ANALOG
MEASUREMENT
ACCESS
ANALOG
MEAS.
CHANNEL
SIMULATE
CONVERT STATUS
CALC.
OUT_D
OUT
PV
ALARM
DETECTION
ALARM_TYPE
ALARM_HYS
LOW_CUT
HI_HI_LIM
HI_LIM
LO_LO_LIM
LO_LIM
OUT_SCALE
XD_SCALE
FIELD_VAL
IO_OPTS
STATUS_OPTS
CUTOFF FILTER
PV_FTIME
L_TYPE
MODE
NOTES:
OUT
_D = BLOCK OUTPUT VALUE AND STATUS
OUT_D = DISCRETE OUTPUT THAT SIGNALS A SELECTED ALARM CONDITION.
FIELDBUS-FBUS_02A
Figure 4-24. Analog Input Function Block Schematic
Uncertain if in Manual mode—The status of the
Output is set to Uncertain when the mode is set to
Manual.
Note
1. The instrument must be in Out of
Service mode to set the status option.
2. The AI block only supports the
Uncertain if in Manual and Propagate
failure. Unsupported options are not
grayed out; they appear on the screen
in the same manner as supported
options.
Filtering
The filtering feature changes the response time of the
device to smooth variations in output readings caused
by rapid changes in input. You can adjust the filter
time constant (in seconds) using the PV_FTIME [18]
parameter. Set the filter time constant to zero to
disable the filter feature.
Signal Conversion
You can set the signal conversion type with the
Linearization Type (L_TYPE [16]) parameter. You can
view the converted signal (in percent of XD_SCALE
[10]) through the FIELD_VAL [19] parameter.
100 X (Channel Value)
−
EU *@0%
FIELD_VAL =
(EU *@100%
−
EU *@0%)
*XD_SCALE values
You can choose from direct, indirect, or indirect
square root signal conversion with the L_TYPE [16]
parameter.
Direct
Direct signal conversion allows the signal to pass
through the accessed channel input value (or the
simulated value when simulation is enabled).
PV = Channel Value
4