Rockwell Automation 1772-LS_LSP,D17726.8.6 PROG/OPER MANUAL-MINI PLC-2/05 User Manual
Page 211
Programming Techniques
Chapter 18
18-3
The technique shown in Figure 18.3 is used when your program does not
contain any other Master Control Restart instruction. The technique shown
in Figure 18.4 is an alternative if an unused Label instruction (chapter 13)
is available.
Figure 18.3
Automatic Restart Using an MCR Instruction
027
01
MCR
MCR
U
027
OFF 01
USER PROGRAM
Figure 18.4
Automatic Restart Using JMP Instruction
027
01
JMP
U
027
OFF 01
USER PROGRAM
06
06
LBL
The values in the data table at start-up depend on whether or not memory
was retained by the back-up battery. If a battery was used, the data table
contains the values that existed when power was removed. If a battery was
not used, the values programmed into EEPROM transfer into the data table
at power-up.
Start-up conditions for automatic start-up (using one of the suggested
programming techniques) are:
initial start-up: remove the battery from the system
in-process start-up after power loss: maintain battery back-up