Sel 411L - Table 14.19 Operator Precedence from Highest to Lowest; Table 14.20 Boolean Operator Summary

P.14.25
Date Code 20151029 Protection Manual SEL-411L Relay
SELOGIC Control Equation Programming
SEL
OGIC Control Equation Operators
Writing SELOGIC control equations requires that you use the appropriate
operators and correct SEL
OGIC control equation syntax to combine relay
elements including analog values, Relay Word bits, incoming control points,
and SEL
OGIC control equation elements within the relay. The operators are
grouped into two types, according to the type of SEL
OGIC control equation in
which you can apply these operators.
Operator Precedence
When you combine several operators and operations within a single
expression, the relay evaluates the operations from left to right, starting with
the highest precedence operators working down to the lowest precedence. This
means that if you write an equation with three AND operators, for example
PSV01 AND PSV02 AND PSV03, each AND will be evaluated from the left
to the right. If you substitute NOT PSV04 for PSV03 to make PSV01 AND
PSV02 AND NOT PSV04, the relay evaluates the NOT operation of PSV04
first and uses the result in subsequent evaluation of the expression. While you
cannot use all operators in any single equation, the overall operator
precedence follows that shown in Table 14.19.
Boolean Operators
Use Boolean operators to combine values with a resulting Boolean value. The
arguments of the operator may be either numbers or Boolean values, but the
result of the operation must be a Boolean value. Combine the operators to
form statements that evaluate complex Boolean logic. Table 14.20 contains a
summary of Boolean operators available in the relay.
Table 14.19 Operator Precedence from Highest to Lowest
Operator Description
(Expression) Parenthesis
Identifier (argument list) Function evaluation
– Negation
NOT Complement
R_TRIG
F_TRIG
Edge Trigger
SQRT, LN, EXP, LOG, COS, SIN, ACOS,
ASIN, ABS, CEIL, FLOOR
Math Functions
* Multiply
/Divide
+Add
– Subtract
<, >, <=, >= Comparison
= Equality
<> Inequality
AND Boolean AND
OR Boolean OR
Ta b l e 1 4 .2 0 B o o l e a n O p e ra to r S um m a r y (Sheet 1 of 2)
Operator Description
( ) Parentheses
NOT Logical inverse
AND Logical AND
OR Logical OR