Rosemount OCX 8800, Instruction Manual

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Instruction Manual
IM-106-880, Rev 2.1
April 2017
OCX 8800
7-26
Convert
Cutoff Filter
Alarm
Detection
PV
Status
Calc.
OUT (mode in man)
OUT (mode in auto)
PV
63% of Change
FIELD_VAL
Time (seconds)
Figure 7-6. Analog Input
Function Block Schematic
Analog
Measurement
HI_HI_LIM
HI_LIM
LO_LO_LIM
LO_LIM
EL
ALARM_HYS
LOW_CUT
ALARM_TYPE
OUT_D
OUT
SIMULATE
L_TYPE
PV_FTIME
MODE
FIELD_VAL
OUT_SCALE
XD_SCALE
IO_OPTS
STATUS_OPTS
NOTES:
OUT = block output value and status.
OUT_D = discrete output that signals a selected alarm condition.
Figure 7-7. Analog Input
Function Block Timing Diagram
PV_FTIME
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 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)
parameter. You can view the converted signal (in percent of XD_SCALE)
through the FIELD_VAL parameter.
3
8
7
4
0
0
8
1
3
8
7
4
0
0
8
0
Access
Analog
Meas.
CHANN