Moeller ps4-201-mm1, Hardware And Engineering

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Start-up behaviour
59
04/
99 AW
B
27-
1184 G
B
Legend for Table 13:
1) If the programs in the memory module and the RAM of
the PLC are not the same, the program in the memory
module (backup program) will be copied to the RAM.
2 ) After the user program has been transferred to the PLC
or after the memory module has been booted, the PLC
is switched to “Not Ready” if the start condition in the
system parameter setup has been set to “Halt” (stop),
i.e. a cold start is required.
Whenever the PLC is started by switching on the
power supply, by pressing the “Reset” button or by
means of the PC, the backup program is compared
with the program in the RAM. If the programs are not
the same, the program in the memory module
(backup program) is copied to the RAM.
If the user program in the memory module is
defective, it is updated, providing the user program
in the RAM is valid. An update is also carried out
every time the user program is transferred from the
PC to the PLC.
Start-up behaviour The PLC can be either cold-started or warm-started.
Cold start
A cold start causes all the data fields (marker ranges,
inputs/outputs, module parameters) to be reset. The
user program is executed from the beginning.