Use logical operators

Use logical operators to verify if multiple conditions are true or false. The result of a logical operation is a BOOL value.
If the comparison is
The result is
true
1
false
0
Use these logical operators.
For this comparison
Use this operator
Optimal data type
logical AND
&, AND
BOOL
logical OR
OR
BOOL
logical exclusive OR
XOR
BOOL
logical complement
NOT
BOOL
The table provides examples of using logical operators.
Use this format
Example
For this situation
Use
BOOLtag
If photoeye is a BOOL tag and your specification says: "If photoeye_1 is on then..."
IF photoeye THEN...
NOT BOOLtag
If photoeye is a BOOL tag and your specification says: "If photoeye is off then..."
IF NOT photoeye THEN...
expression1 & expression2
If photoeye is a BOOL tag, temp is a DINT tag, and your specification says: "If photoeye is on and temp is less than 100 then..."
IF photoeye & (temp<100) THEN...
expression1 OR expression2
If photoeye is a BOOL tag, temp is a DINT tag, and your specification says: "If photoeye is on or temp is less than 100 then...".
IF photoeye OR (temp<100) THEN...
expression1 XOR expression2
If photoeye1 and photoeye2 are BOOL tags and your specification says: "If:
photoeye1 is on while photoeye2 is off or
photoeye1 is off while photoeye2 is on
then..."
IF photoeye1 XOR photoeye2 THEN...
BOOLtag := expression1 & expression2
If photoeye1 and photoeye2 are BOOL tags, open is a BOOL tag, and your specification says: "If photoeye1 and photoeye2 are both on, set open to true"
open := photoeye1 & photoeye2;
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