Hysteresis_LREAL (FB)

FUNCTION_BLOCK Hysteresis_LREAL

This function block will set the output variable to TRUE, if the input value \(x \in \mathbb{R}\) is smaller than a lower bound \(x_{u} \in \mathbb{R}\).
It will set the output variable to FALSE, if the input value \(x\) exceeds the upper bound \(x_{o} \in \mathbb{R}\).
If \(x\) lies between the lower and the upper bound, the value of the output variable will rest unchanged by the module.
InOut:

Scope

Name

Type

Comment

Input

lrValue

LREAL

input value \(x \in \mathbb{R}\)

lrLimitPos

LREAL

upper bound \(x_{o} \in \mathbb{R}\)

lrLimitNeg

LREAL

lower bound \(x_{u} \in \mathbb{R}\)

Output

xOut

BOOL

FALSE: If \(x > x_{o} \land x_{u} < x_{o}\)
TRUE: If \(x < x_{u} \land x_{u} < x_{o}\)
xOut” else