Timer instructions
339
Part II IEC Instructions
SUB_TIME
Subtract TIME
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.
PLC types
Availability of SUB_TIME (see page 1331)
Data type I/O Function
TIME 1st input minuend
TIME 2nd input subtrahend
TIME output result
Description
SUB_TIME subtracts the value of the second input variable from the value of the first input variable
and writes the result into the output variable.
Data types
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.
In this example the input variables (minuend and subtrahend) have been declared. Instead, you
may enter constants directly at the input contacts of a function.
Body
Subtrahend is subtracted from minuend. The result will be written into result.
LD
ST
When programming with structured text, enter the following:
result:= SUB_TIME(minuend, subtrahend);