ProSoft Technology MVI56-AFC User Manual
Page 39
MVI56-AFC ♦ ControlLogix Platform
Meter Channel Functionality
Liquid and Gas Flow Computer
User Manual
ProSoft Technology, Inc.
Page 39 of 316
February 25, 2011
3.6.8 Process Input Scaling
The module allows you to either pre-scale the process inputs via ladder logic for
use in the measurement calculations, or provide unscaled values from the analog
input modules directly. In the second case, the scaling is done internally. You can
directly enter the zero-scale, the full-scale, and the default values for each of the
process variable inputs through the configuration window. Pre-scaled values may
be transferred as floating point or as scaled integer.
When selecting scaled integer, the integer values are scaled as follows:
Scaled Integer
Variable
Format
Example
Temperature
Two decimal places implied
A value of 1342 would be
equivalent to 13.42°C
Pressure
No decimal places implied for SI
units (kPa) and one decimal
place implied for U.S. units (psi).
A value of 200 would be
equivalent to 200kPag
Differential Pressure
Two decimal places implied for
inches of H2O and 3 places for
kPa
A value of 35142 would be
equivalent to 35.142kPa
Density (kg/m3)
One implied decimal place
A value of 5137 would be
equivalent to 513.7 kg/m3
Density (Relative Density)
Four implied decimal places
A value of 10023 would be
equivalent to 1.0023 60F/60F.
Density (API)
Two implied decimal places
A value of 8045 would be
equivalent to 80.45 °API.
When selecting the 4 to 20mA process input scaling, the module uses the
following ranges:
4 to 20mA
Processor
Module
0%
100%
SLC
MVI46-AFC
3277
16384
ControlLogix
MVI56-AFC
13107
65535
CompactLogix
MVI69-AFC
6241
31206
PLC
MVI71-AFC
819
4095
Quantum
PTQ-AFC
4000
20000
The module uses the configured values for zero and full scale to interpret the
process input scaling.
In the Meter Monitor window, the raw values as transferred from the processor
are shown at the "Last Raw" column and the converted values are shown at the
"Scaled Avg" column.