Insert the card into your PLC. The PLC should now be able to perform a "Module Erase" and accept a new hardware configuration. Hardware Requirements
Switch to (Memory Reset) and hold it until the STOP LED stops flashing and lights up continuously (approx. 5 seconds). Release the switch .
If you have a PG (Field PG M5/M6, etc.): siemens mmc card format tool
Instead of a third-party "format tool," use the following built-in methods provided by Siemens software and hardware: 1. Hardware Reset via CPU ( Go to product viewer dialog for this item.
The Siemens MMC card format tool is not a simple, official software download. It is a set of practices ranging from using the CPU's MRES switch for a basic reset, to using specialized hardware like the USB Prommer with official Siemens software, and finally, to employing powerful community tools like S7imgWR for disaster recovery. Insert the card into your PLC
Unlike standard consumer SD or MMC cards, the Siemens SIMATIC Micro Memory Card (MMC) for S7-300 series CPUs is a specialized piece of hardware with a proprietary, non-Windows-compatible file system. These cards act as the CPU's load memory, and new S7-300 CPU modules physically lack internal load memory, making the MMC an obligatory component for operation.
Siemens SIMATIC Micro Memory Card (MMC) is a cornerstone of industrial automation, specifically for Siemens S7-300 and S7-400 PLC series 5 seconds)
: Hold the CPU selector switch in the MRES position until the STOP LED stays lit (approx. 9 seconds).
According to Siemens Industry Support , you cannot perform a standard operating system "format" on a SIMATIC Micro Memory Card. Instead, you perform a or a specific re-initialization within the STEP 7 environment. Method 1: Formatting/Resetting via S7-300 CPU (Recommended)
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Remember the three golden rules: