Size Restrictions For The User Program; User Program Object Restrictions - Omron NJ-series User Manual

A-10 Size Restrictions for the User
Program
There are size restrictions for the user program due to the limitations of the memory capacity in the
CPU Unit and other factors. If you exceed these restrictions, errors will occur during operation. This
section describes each of the size restrictions of a user program that is created in a CPU Unit.
You can check the approximate sizes of the user program and variables with the memory display func-
tions of the Sysmac Studio.
Be careful not to exceed these restrictions when you create the user program. The restrictions that are
given in this section, however, are only reference values for use as guidelines. We recommend that you
ensure ample leeway for the restrictions to allow for the possibility of future user program expansion as
well as for other reasons.
Precautions for Correct Use Precautions for Correct Use
Errors can occur during online editing even if the user program size restrictions are not
exceeded. This is because even if you change the user program with online editing, other data
that is allocated in the memory of the CPU Unit may remain. If errors occur, change the Control-
ler to PROGRAM mode and transfer the user program to the Controller again to reset the errors.
A-10-1

User Program Object Restrictions

This section describes the restrictions to user program objects. There are restrictions for the following
objects.
• POU
• Variables
• Data type definitions
• Constants (literals)
POU Restrictions
There are restrictions both on POU definitions and POU instances.
 POU Definition Restrictions
POU definitions are subject to the following restrictions.
Maximum number of programs
Maximum value of the following: Number of function block
definitions + Number of function definitions + Number of lad-
der diagram sections
Maximum total number of input, output, and in-out variables
in function block and function definitions
NJ-series CPU Unit Software User's Manual (W501)
Restriction
Appendices
CPU Unit model
NJ501- NJ301-
500
3,000
64
500
750
64
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