Insert The Micro Memory Card Into The Cpu - Siemens SIMATIC S7-300 Hardware And Installation Manual

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 when power is off or when the CPU is in STOP state and
when no PG performs a 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. Switch the CPU to STOP.
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.
To you to remove the micro memory card, the module slot has an ejector device
(see the CPU Data Reference Manual, figure in the chapter entitled Elements
and Assembly of the CPU).
Use a small screwdriver or ball-point pen to remove the MMC.
3. Insert the ("new") MMC into the MMC slot with the bevelled edge of the MMC
pointing towards the ejector.
4. Apply a slight pressure to the CPU to guide it into the CPU until the MMC snaps
into place.
5. Reset the CPU memory (see Commissioning the modules, resetting the CPU
memory).
Figure 9-3 Insert the micro memory card into the CPU
Inserting/Removing an MMC in POWER OFF mode
If you replace MMCs while the power is switched off, the CPUs
• will recognize a physically identical MMC with changed content
• a new MMC with the same content as the old MMC
After POWER ON, they request a memory reset.
Also refer to the CPU Data Reference Manual, Chapter Structure and
Communication Functions of CPU 31xC, section SIMATIC Micro Memory Card
(MMC).
S7-300 Programmable Controller Hardware and Installation
A5E00105492-02
Commissioning
9-9