Inserting The Memory Card In The Cpu31Xc - Siemens SIMATIC S7-300 Hardware And Installation Manual

Commissioning
Inserting/replacing a SIMATIC Micro Memory Card (MMC)
Note
Loading the user program and, therefore, operation of a CPUs 31xC is only
possible if an MMC is inserted.
Removal of the MMC causes CPU 31xC to go into STOP mode and request
memory reset.
Caution
Data on a SIMATIC Micro Memory Card can be corrupted if you remove the card
during write access. In this case you might have to insert the MMC memory in your
PG to delete it, or you format the card in the CPU.
Never remove an MMC in RUN mode. Always remove it in power off or CPU STOP
state, when the PG does not write access the card. Disconnect the communication
lines if you cannot safely exclude active write access functions from the PG (e.g.
load/delete function block).
1. Set the CPU 31xC to STOP mode.
2. Is an MMC inserted?
If yes, make sure that no PG write access functions (e.g. load block) are active.
If you cannot ensure this state, disconnect all communication lines of the CPU.
Now, push in the ejector and remove the MMC.
In order to make it possible for you to remove the Micro Memory Card we have
equipped the module slot socket with an ejector (refer to the Reference Manual
CPU Data, figure in Chapter Elements and Assembly of the CPU).
Use a small screwdriver or pen to remove the MMC.
3. Insert the ("new") MMC into the MMC slot with the chamfered edge of the MMC
pointing to the ejector.
4. Insert the MMC under slight pressure into the CPU 31xC until it latches.
5. Reset the memory of CPU 31xC (refer to Chapter Commissioning Modules,
Resetting CPU memory)
Figure 8-3 Inserting the Memory Card in the CPU31xC
Inserting/Removing an MMC in POWER OFF mode
If you replace the MMC in POWER OFF mode, CPUs 31xC
• will recognize a physically identical MMC with changed content
8-8
S7-300 Programmable Controller Hardware and Installation
A5E00105492-01