Function Blocks
Function Block Reference Guide
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2.47 4OR Function Block
Description
The
4OR
label stands for the inclusive
OR (4 Inputs) Boolean logic function
.
This block is part of the
Logic
and
Fast Logic
categories. It looks like this graphically on the Control Builder.
OR
Fast Logic
Function
Turns digital output (OUT)
OFF
when inputs X1 through X4 are
OFF
. Thus,
• If input X1
o
r X2
or
X3
or
X4 are
ON
, then:
OUT = ON.
• If all inputs are OFF, then:
OUT = OFF.
Input
X1
= First digital signal.
X2
= Second digital signal.
X3
= Third digital signal.
X4
= Fourth digital signal.
Output
OUT
= Digital signal controlled by status of input signals
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.
Input State
You can invert Input 1, 2, 3, 4, or all. If the input is
inverted, an input line that is ON is seen as OFF. (“N”
appears on the Icon next to the inverted input.)
NOTE: Unused Inputs default to 0.
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