PLC device configuration
6.1 Configuring the operation of the PLC system
S7-200 SMART
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System Manual, V2.3, 07/2017, A5E03822230-AF
Clearing the PLC using a reset-to-factory defaults memory card
For standard CPUs, you can clear the PLC using a previously-made reset-to-factory defaults
memory card.
WARNING
Inserting a memory card into a CPU
Inserting a memory card into a CPU in RUN mode causes the CPU to automatically
transition to STOP mode. You cannot change the CPU to RUN mode if a memory card is
inserted.
Inserting a memory card into a running CPU can cause disruption to process operation,
possibly resulting in death or severe personal injury.
Always ensure that the CPU is in STOP mode (Page 46) prior to inserting a memory card.
To clear the PLC using this card follow these steps:
1.
Insert the reset-to-factory-defaults memory card. The CPU goes to STOP mode and
flashes the STOP LED.
2.
Power cycle the CPU. The CPU flashes the RUN/STOP LEDs until the reset is complete
(about one second), and then flashes the STOP LED indicating that the reset is finished.
3.
Remove the memory card.
4.
Power cycle the CPU. The CPU is reset to the factory defaults. The former IP address
and baud rate settings are cleared, but the time-of-day clock is unaffected.
After the CPU is reset, you can assign a new password and begin programming, or load a
program from another program transfer memory card (Page 97) or from your hard disk.
Note
If you load a password-protected program from a memory card or file on your hard disk, you
must enter the password to access the protected areas. You cannot access a password-
protected program component without a password, nor can you clear an assigned password
without entry of the password.