Structure And Functions Of The Memory Cards - Siemens SIMATIC S7-400 Manual

2.7

Structure and Functions of the Memory Cards

Order numbers
The order numbers for memory cards are listed in the technical specifications.
Structure
The memory card is slightly larger than a credit card and protected by a strong metal casing.
It is inserted into a front slot of the CPU. The memory card casing is encoded to allow only
one position of insertion.
Front view
Figure 2-4
Function
The memory card and an integrated memory area on the CPU together form the load
memory of the CPU. During runtime, the load memory contains the complete user program
including comments, symbols and special additional information that allows the
decompilation of the user program, and all module parameters.
What Is Stored in the Memory Card
The following data can be stored on memory cards:
● User program, in other words, blocks (OBs, FBs, FCs, DBs) and system data
● Parameters which determine the behavior of the CPU
● Parameters which determine the behavior of the I/O modules.
● In STEP 7 V5.1 or higher, all project data on suitable Memory Cards.
S7-400 Automation System, CPU Specifications
Manual, 10/2006, 6ES7498-8AA04-8BA0
Side view
Rating plate
Grip
Structure of the Memory Card
2.7 Structure and Functions of the Memory Cards
Structure of a CPU 41x
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