Function Blocks
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Function Block Reference Guide
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2.14 BOOL Function Block,
continued
Output
ERR =
error during execution of the equation.
Error = ON. No Error = OFF
OUT
= Calculated Output (ON or OFF)
A maximum of 50 tokens per equation is allowed. A token is an operator, a variable, or a pair of
parentheses.
ATTENTION
— Note the following user tips:
•
Use only the following list of words and characters in an equation:
–
AND - logical AND,
–
OR - logical OR,
–
NOT - unary NOT,
–
XOR - exclusive OR, or
–
"( )", "[ ]", and "{ }" parentheses - three types.
•
A left parenthesis must have a matching right parenthesis.
•
The matching parenthesis must be the same type, that is, "( )", "[ ]", or "{ }".
•
Parentheses may be nested to any depth.
•
Logicals AND, OR, and XOR must have a left and right operand.
•
Unary NOT must have one operand to the right, and the operand must be enclosed in parentheses; for
example, NOT(G).
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.
Configuration Parameters
You must configure the BOOL function block
parameters to the desired value or selection that
matches your operating requirements.
describes the parameters and the value or
selection.