Select the drive letter corresponding to the MMC card. Triple-check this selection. Selecting the wrong drive (like your hard drive) could cause severe data loss.
Release and immediately flick to MRES again within 3 seconds. The STOP LED will blink rapidly to indicate the reset is complete. : Go to Online & Diagnostics for the connected CPU.
And MMC is here a Micro Memory Card which has the same dimensions as a SD card. An MMC should allways be an original Siemens part. sieportal.siemens.com siemens mmc card format tool
If the PLC fails to complete the MRES process, the card might be permanently damaged.
The Siemens MMC card format tool is a software utility designed to format and manage MMC cards used in Siemens devices. MMC cards are small, removable memory cards that store data, programs, and configuration settings for Siemens industrial control systems. The tool allows users to format MMC cards, ensuring they are compatible with Siemens devices and can store data efficiently. Select the drive letter corresponding to the MMC card
Do not use standard PC USB SD card readers to format S7-300 MMCs. They require special hardware timing that only a Siemens Prommer or the CPU itself provides. Summary of Best Practices Always have a backup of your project before formatting. Use the MRES switch for quick, onsite resets.
Has your team ever recovered a "dead" MMC card? Let me know in the comments! 👇 Release and immediately flick to MRES again within 3 seconds
The Essential Guide to Siemens MMC Card Format Tools If you work with Siemens S7-300 or S7-400 PLCs, you know that the is a specialized piece of hardware. Unlike standard SD cards, these proprietary cards use a unique internal file system that Windows cannot natively read or format.
For modern engineering, the go-to solution is the . While it handles much more than just formatting, it is the most reliable modern interface for managing memory cards.