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Entry type: FAQ, Entry ID: 36981866, Entry date: 08/06/2009

How can you determine the size of the load memory and main memory of a SIMATIC S7-300/400 CPU?

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The example shown here explains how you can use your project to determine the size of the load memory and main memory in order to define the size of the memory cards needed, for example.

  1. Open the project and mark the block folder.
  2. Right-click and select "Object Properties".

    Fig. 01
  3.  In the new window you select the "Blocks" tab.

    Fig. 02
  4. You can also determine the size of the load memory by adding the user program and the system data (red marking),
    for example, 428 bytes + 710 bytes = 1138 bytes
    The memory card used in the S7 CPU must have this size at least.
  5. The required size of the CPU's main memory is displayed directly (yellow marking).

Memory size, MMC, MC

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