With logical operators, you can test several conditions as either TRUE or FALSE.
Operator |
Description |
AND |
Logical AND |
OR |
Logical OR |
NOT |
Logical NOT |
Examples:
Command |
Result = (PV12 = 10 AND PV13 = 2); |
Comment |
If PV12 equals 10 and PV13 equals 2 then Result is TRUE(1) |
Expression |
Motor_1 AND Motor_2; |
Comment |
If both Motor_1 and Motor_2 are TRUE, that is Digital bits are 1 or ON, then the expression is TRUE |
Expression |
PV12 = 1 OR PV13 > 2 OR Counter <> 0; |
Comment |
If either PV12 equals 1 or PV13 is greater than 2 or Counter is not equal to 0, then the expression is TRUE |
Command |
Result = (Motor1_Ol OR Motor2_Ol); |
Comment |
If either Motor1_Ol or Motor2_Ol is TRUE, that is Digital bit is 1 or ON, then Result is TRUE (1) |
Command |
IF NOT PV12 = 10 THEN ... |
Comment |
If PV12 does not equal 10 then the result is TRUE. This is functionally identical to IF PV12 <> 10 THEN . . . |
Expression |
NOT Tag_1; |
Comment |
This expression is TRUE if Tag_1 = 0. This is commonly used for testing digital variables |
See Also