User Manual

LOGO! functions
4.4 Special functions list - SF
LOGO!
194 Manual, 06/2014, A5E33039675
Timing diagram
Functional description
A 0 to 1 transition at input En saves the value of the signal at the analog input Ax. This saved
process variable is referred to as "Aen".
Both the analog actual values Ax and Aen are multiplied by the value at parameter A (gain),
and parameter B (offset) is then added to the product:
(Ax • gain) + offset = Actual value Aen, when input En changes from 0 to 1, or
(Ax • gain) + offset = Actual value Ax.
Output Q is set when the signal at input En = 1 and if the actual value at input Ax is out of
range of Aen - Δ
2
to Aen + Δ
1
.
Output Q is reset, when the actual value at input Ax lies within the range of Aen - Δ
2
to Aen+
Δ
1
, or when the signal at input En changes to lo.
Setting the Par parameter
The gain and offset parameters are used to adapt the used sensors to the respective
application.
View in programming mode:
View in parameter assignment mode (example):