S5-115F Manual
System Startup
4.1.5
Battery Backup
A battery is absolutely necessary for program and data backup on RESTART after POWER OFF.
Flags, timers, and counters are always set to zero in the ”RESTART” mode.
Note
If a battery failure is detected in the ”RESTART” mode after POWER ON, the PLC goes
into the ”STOP” mode.
4.1.6
Overall Reset
It is recommended that you perform the ”Overall Reset” function before entering a new program.
Overall Reset clears the following items:
•
The PLC program memory,
•
All data (flags, timers, and counters),
•
All error DBs.
Note
Without Overall Reset, information is maintained even if the program is overwritten.
You can perform Overall Reset on the CPU in the following ways:
•
in online mode via the ”Overall Reset” programmer function
•
by replacing the memory submodules
•
via the switches on the CPU.
Overall Reset via the switches on the CPU:
1.
Hold the switch in the OR position
2. Switch the mode selector twice from RUN to STOP.
The red and green LEDs go out briefly during Overall Reset.
!
Important
Overall Reset is of great significance in safety mode because it leads to the loss of error
information.
An Overall Reset should only be carried out after repair of all defective components
and is done at the user's own risk!
EWA 4NEB 811 6148-02
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