Lsel Function Block; Figure 2-29 Lsel Function Block Example - Honeywell UMC800 Reference Manual

Function Blocks

2.32 LSEL Function Block

Description
The LSEL label stands for Low Selector. This block is part of the Signal Selectors category. It looks like
this graphically on the Control Builder.
Function
Selects lower of two analog input values (X & Y) for output.
Indicates when Y is lower than X.
• If X < or = Y, then: OUT = X; YLO = OFF.
• If X > Y, then: OUT = Y; YLO = ON.
Input
X = Analog value.
Y = Analog value
Output
OUT = Lower analog value.
YLO = 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 2-29 shows a Function Block Diagram using an LSEL function block to monitor two analog inputs
to activate an alarm signal tag.
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Figure 2-29 LSEL Function Block Example

Function Block Reference Guide 3/99