
B-63983EN/02 1.OVERVIEW OF PMC
- 13 -
1.3 SEQUENCE PROGRAM CREATION PROCEDURE
This section briefly explains how to create a program for providing
sequence control for a machine tool by using the Ladder language as an
example. When creating a sequence program, see the necessary
manual for editing after understanding the contents of this chapter
thoroughly.
1.3.1 Determining Specification
First, determine the specifications of the control target. Calculate the
number of I/O signals, and determine the interfaces of the I/O signals.
In this step, creation of interface specifications is recommended.
1.3.2 Creating Ladder Diagram
After determining specifications, represent control operations with a
ladder diagram. Timer, counter, and other functions that cannot be
represented by relay symbols are called functional instructions.
Represent these functional instructions with corresponding symbols.
When using offline programmer or built-in edit function explained in
"Editing Sequence Program" in the next subsection, you can enter a
sequence program in a ladder diagram form. At the time of sequence
program editing, you can make entry while creating a ladder diagram
on the display screen, so you need not prepare a ladder diagram in
advance.
If you want to create a sequence program efficiently, however, it is
recommended that you should create a ladder diagram in advance.
Ladder diagrams are referenced as maintenance drawings by FANUC
maintenance engineers, maintenance engineers of machine tool
builders, and maintenance engineers of end users not only domestically
but also in foreign countries. Therefore, try to create as intelligible
ladder diagrams as possible.