Rockwell Automation T7833 ICS Regent+Plus Math Package for Winternet - Manual (Page 25)

Math Package for W INTERPRET (T7833)
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function block, and will vary according to type of data used
and the complexity of the equation.
Table 11. Execution Speeds.
Operation
Format
Minimum Speed
(msec.)
Add + 63
Subtract - 87
Multiply * 56
Divide / 56
Logarithm LOG(x) 45
Natural Log LN(x) 62
Square root SQRT(x) 45
Exponentiation X^Y 90
e raised to the X EXP(x) 1845
Equality = 15
There are two general rules for creating the most efficient
floating point equations:
1. Simplify equations. Using parentheses will increase the
execution speed of the equation.
2. Store intermediate results in local or shared floating point
registers. Other data types are converted to floating point
prior to equation execution. The fewer times a conversion
is performed, the faster the execution.
Safety Considerations
The floating point math function block is TÜV certified for
Risk Class 5 as non-interfering. These function blocks may
only be used in safety critical applications if they do not
perform any control actions that affect the value of Risk Class
5 safety critical variables.