Panasonic FP Series

Arithmetic instructions
81
Part II IEC Instructions
EXP
Exponent of input variable to base e
To add an enable input and enable output to the instruction, select [With EN/ENO] from the
"Instructions" pane (LD, FBD or IL editor). To reuse an instruction select "Recently used" from the
context menu or press <Ctrl>+<Shift>+<v> in the programming window.
The number of steps may vary depending on the PLC and parameters used, see
also Table of Code Intensive Instructions in the online help.
PLC types
Availability of EXP (see page 1320)
Data type I/O Function
REAL input input value between -87.33 and +88.72
REAL output as input exponent of input variable to base e
No. IEC address Set If
R9007 %MX0.900.7 permanently
R9008 %MX0.900.8 for an instant
 input variable does not have the data
type REAL or input variable is not >
-87.33 and < 88.72
R900B %MX0.900.11 permanently  output variable is zero
R9009 %MX0.900.9 for an instant  processing result overflows the output
variable
Description
EXP calculates the power of the input variable to the base e (Euler’s number = 2.7182818) and
writes the result into the output variable. The input variable has to be greater than -87.33 and
smaller than 88.72. This function is the reversion of the LN (see page 78) function.
Data types
Error flags
Example
In this example, the same POU header is used for all programming languages. For an example
using IL (instruction list), please refer to the online help.
POU header
All input and output variables used for programming this function have been declared in the POU
header.
This example uses variables. You can also use a constant for the input variable.
Body
The power of input_value is calculated to the base e and written into output_value.
LD
ST
When programming with structured text, enter the following:
output_value:=EXP(input_value);