Rockwell Automation 1756-XXXX ControlLogix Analog I/O Modules User Manual
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Publication 1756-UM009C-EN-P - December 2010
Chapter 3 ControlLogix Analog I/O Module Features
Difference Between Integer and Floating Point
The key difference between choosing integer mode or floating point mode is
that the integer is fixed between -32,768…32,767 counts and floating point
mode provides scaling to represent I/O data in specific engineering units for
your application. Module resolution remains constant between the formats at
0.34 µA/count.
For example, the table shows the difference in the data returned from the
1756-IF6I module to the controller between data formats. In this case, the
module uses the 0 mA…20 mA input range with 0 mA scaled to 0%
and 20 mA scaled to 100%, as shown on page 50.
1756-IF6I Module using different data types
Signal Value
Fixed Number of Counts
in Integer Mode
Data Representation in Floating
Point Mode (Engineering Units)
0 mA
-32768 counts
-25%
4 mA
-20341 counts
0%
12 mA
4514 counts
50%
20 mA
29369 counts
100%
21.09376 mA
32767 counts
106.25%