Omron CX-PROGRAMMER V8.1 Operation Manual page 204

Procedures
• For CJ2-series CPU Units, there is no restriction on the number of steps
that can be added to or deleted from a function block definition during one
online editing operation.
• Online editing is not possible for ST programs that exceed 4 Ksteps
(except for CJ2-series CPU Units).
• A maximum of 0.5 Ksteps can be added to or deleted from an ST program
during one online editing operation (except for CJ2-series CPU Units).
• After performing online editing, do not turn OFF the power supply to the
PLC until the CPU Unit has finished backing up data to the built-in flash
memory (i.e., until the BKUP indicator goes OFF). If the power supply is
turned OFF before the data is backed up, the data will not be backed up
and the program will return to the status it had before online editing was
performed.
Section 6-1
179