Rockwell Automation AutoMax Enhanced Ladder Language Reference Manual - Manual (Page 288)

AĆ16
You can choose from the following initialization methods for a variable from its Variable
Properties tab:
D No Initialization (No Init.)
D User Specified Value
D Retained Value
A.6.1 About the No Initialization (No Init.) Method
When a variable is configured to use no initialization, the value it contains is determined
by the buffering of inputs and outputs and by program execution. For global and local
variables, the default initialization is No Initialization. Local and global variables defined
as using no initialization are set to 0 when the program in downloaded to the Processor.
Global outputs are not cleared at the start of the first scan.
This table explains the value of variables under specific conditions:
Variable Type
Ladder Program
Condition
NonĆvolatile
global
Volatile global Local
Power fail values retained,
unless battery
values lost and
set to zero
StopĆAll
unless battery
backup fails
set to zero
values retained
Program stopped values unchanged by operation;
programs that are still running may
cause values to change