Rockwell Automation 1757-ABRIO Process Remote I/O (RIO) Communication Interface Module - Manual (Page 28)

26 Publication 1757-UM007D-EN-P - December 2008
Chapter 2 Configure the 1757-ABRIO Module
Scaling Part of the configuration procedure for analog modules is entering
scaling values. The 1757-ABRIO module performs scaling between
raw I/O data and floating point user values.
You can send floating point output values to the 1757-ABRIO module
which it converts to raw output values using the scaling values you
supplied in the configuration. Similarly, the 1757-ABRIO module
converts raw input data to floating point values, using the scaling you
enter. The 1757-ABRIO module supports scaling values from -3.4e38
to 3.4e38. Scaling is done on a per-channel basis.
Input Scaling
For analog input modules, you must supply the floating point values
to which you want the minimum and maximum raw data scaled.
Minimum corresponds to the lowest raw value.
Maximum corresponds to the maximum raw value.
EXAMPLE
If a raw input range is 1 5 V dc and you set the minimum
scaling value to 12.3 and the maximum scaling value to 77.4,
a raw input voltage of 1 produces a scaled input value of 12.3.
A raw input voltage of 5 V dc produces a scaled input value of
77.4
A raw input value outside the range of 1 5 V dc produces an
input of NaN (not a number). Modules also have underrange
and overrange bits to indicate data overflows.