Rockwell Automation 1794-IF4I, -OF4I, IF2XOF2I, -IF4IXT, -IF4ICFXT, -OF4IXT, IF2XOF2IXT FLEX I/O Isolated Analog Modules - Manual (Page 133)

Publication 1794-6.5.8 - January 2010
Calibrating Your Module 131
Scaling Inputs
Inputs are scaled using the y = mx + b linear formula, as illustrated by
the three types below.
The gain, m, and offset, b, coefficients are calculated as follows:
m = Desired Range / Input Range
b = Desired value when input returns zero (type 1 & 2)
b = – m( Δ x) + ( bottom of Desired Range ) (type 3)
Configu-
ration Nominal
Range Data Type Scale
Figure Output
Range
Δ X
1 4–20mA signed 2’s complement Type 2 30840 NA
2 +10V signed 2’s complement Type 1 63938 NA
3 +5V signed 2’s complement Type 1 62416 NA
4 0–20mA signed 2’s complement % Type 2 10000 NA
5 4-20mA signed 2’s complement % Type 2 10000 NA
6 0–10V signed 2’s complement % Type 2 10000 NA
7 +10V signed 2’s complement % Type 1 20000 NA
8 0–20mA binary Type 2 62415 NA
9 4–20mA binary Type 2 61681 NA
A 0–10V binary Type 2 63938 NA
B 0–5V binary Type 2 62415 NA
C +20mA offset binary Type 3 62416 1560
D 4–20mA offset binary Type 3 30840 32768
E +10V offset binary Type 3 63938 799
F +5V offset binary Type 3 62416 1560