Function Blocks
Function Block Reference Guide
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2.28 HSEL Function Block
Description
The
HSEL
label stands for
High
Selector.
This block is part of the
Signal Selectors
category. It looks like
this graphically on the Control Builder.
Function
Selects higher of two analog input values (X & Y) for output.
Indicates when Y is higher than X.
• If X > or = Y, then:
OUT = X; YHI = OFF.
• If X < Y, then:
OUT = Y; YHI = ON.
Input
X = Analog value.
Y = Analog value
Output
OUT = Higher analog value.
YHI = Digital signal. (ON when Y>X.)
Block Properties
Double click on the function block to access the function block properties dialog box.
Block Order (Read Only)
You can change the assigned execution order number by selecting “Execution Order” in the “Configure”
menu and arrange the order to suit your control strategy.
Example
Figure 2-25 shows a Function Block Diagram using an HSEL function block to monitor two analog inputs
to activate an alarm signal tag.
Figure 2-25
HSEL Function Block Example