Allen-Bradley 2080-LC20-20QWB User Manual page 19

Rockwell Automation Publication 2080-UM005B-EN-E - March 2015
Insufficient Controller Memory Example
Controller Memory
(for User Program + Data)
Used memory
Limitations of RMC
Take note of the following limitations when using the Run Mode Change (RMC)
feature:
• Configuration changes cannot be made (for example, change filter times).
• Up to 2KB of logic (approximately 150 boolean instructions) and user
variables and can be added for each Test Logic.
• Total memory allocated for RMC (cumulative of all Test Logic Changes)
can be increased from 2KB to 8KB, but the 2KB limit for logic and user
variables per Test Logic remains.
• A total of 20 POU (Program Organizational Units) can be added for each
RMC (for example, if you currently have 5 POU, you can add 20 more for
a total of 25 POU).
• If a User Defined Function Block is modified that changes the local
variables, the local variables will be reinitialized or reset to zero and a
warning message will be shown during the build. If you want to reapply the
initial value, right-click on the UDFB and select Refactor -> Reset Initial
Values of Instances.
• Exchange files cannot be imported when in RMC because it is considered a
configuration change.
• Global variables cannot be deleted or modified in RMC, but can be added.
To delete or modify a global variable, the workbench must be disconnected
from the controller.
• If you create a global variable in RMC, it will not be shown in the LCD
display.
WARNING: If you delete the output rung when in Run Mode Change and
accept the changes, the output on the controller will remain ON.
See Using Run Mode Change on page 150
feature.
About Your Controller
RMC Memory
(Default size = 2KB)
Error will occur due to insufficient
controller memory remaining
for an example on how to use this
Chapter 2
Free RMC memory
11